April 2021

Global Astronomy Magazine

Published by the Explore Alliance Chief Editorial Staff: Marcelo de Oliveira Souza David H. Levy © Explore Alliance Duplication of contents in full or part is prohibited unless prior authorization by Explore Alliance has been obtained. Unless an advertisement in the publication contains a specific endorsement by the Explore Alliance, it has not been tested by, approved by or endorsed by the Explore Alliance. Explore Alliance 1010 S. 48th Street Springdale, AR 72762 Phone: 949-637-9075 o o o Sky’s Up digital magazine is made possible through a generous contribution from Explore Scientific. 2 contents Window to the Sun Perseverance Hydrogen-Alpha systems are key to studying our star — Page 24 Mars 2020 mission continues search for life on Red Planet — Page 20 Brasstronomy Astrolabe project brings ancient astronomy into the present day — Page 38 on the cover Two name plates mounted on the Mars Perseverance rover’s robotic arm are visible in this composite image, made from photos taken by the rover’s left Navcam on Sol 12 of its mission (March 2, 2021). The rover’s name, “Perseverance,” is inscribed on the plate attached to its forearm, and the mission name, “Mars 2020,” is shown on its upper arm. Running vertically along the right side of the mission name plate is a string of 17 letters and numbers. These characters form a unique product identification number (PIN) similar to the Vehicle Identification Number (VIN) on vehicles on Earth, but signifying that this is an off-road vehicle. Issued in part by the Society of Automotive Engineers, a PIN or VIN number provides a unique vehicle identifier, while encoding information about the vehicle’s characteristics and manufacture. Perseverance’s PIN can be decoded to reveal clues about its destination, mission objective and power source. For more information about the mission, go to: mars.nasa.gov/mars2020. COURTESY OF NASA/JPL-Caltech A Guide to the Sky............Pg. 8 Wonderful Universe .......Pg. 14 The Art of Astronomy... Pg. 54 Seasonal Sky Calendars Pg. 65 Global Astronomy Magazine

3 from the editor Hi!!! Bright radiant star in the night sky. A Red Star. Arouses attention and admiration. In the mythology of several civilizations, he was associated with the gods of war. Nergal, in ancient Babylon. For Hindus, Mangal, Angakara and Kuja, names that in Sanskrit mean auspicious, burning coal and the just. Har Decher, red Horus, in ancient Egypt. Ares, for the Greeks. Mars, for the Romans. It is curious that before associating the god Mars with the Greek god of war Ares, he was for the Romans the god of agriculture. Another curiosity is that the city of Cairo, current capital of Egypt, has its name derived from Al Qahira, an ancient Arab name for Mars. In Greek mythology Ares, the god of war, had three children with Aphrodite, the goddess of love. Two of them were Phobos, fear, and Deimos, panic. They have always accompanied him on the battlefield. The Greek Aristotle (384-322 B.C.) observed an occultation of Mars by the Moon. During the occultation, the Moon passes in front of Mars. From this observation he concluded that Mars was more distant from the Earth than the Moon. The Danish Tycho Brahe, in the period from 1580 to 1600, made the most accurate observations, at the time, of the position of Mars in the sky in relation to the constellations. Based on these data, the German Johannes Kepler published in 1609 his first two laws of planetary motion. The Italian Galileo Galilei observed Mars for the first time with the aid of a telescope. With the construction of better telescopes, more information about the planet was emerging. The Dutchman Christiaan Huygens, in 1659, determined, for the first time, the size and the period of rotation of Mars. In 1877 the two moons of Mars, Deimos and Phobos, were discovered by the American Asaph Hall. In the same year, the Italian Giovanni Virginio Schiaparelli reported the observation of canali (channels) on the Martian surface. The term was translated into English as canals instead of channels. Providing the impression that it referred to artificial channels. This fact made us imagine the existence of a civilization on Mars. The American Percival Lowell stimulated by this idea built an observatory in 1894. From where, for many years, he studied the planet Mars. He published three books, Mars (1895), Mars and Its Canals (1906) and Mars as the Abode of Life (1908). In these books, based on his observation of the channels, he imagines the existence of a civilization on Mars in the past. Few astronomers at the time observed channels on the Martian surface. Based on these ideas, several science fiction books were written. In the popular imagination the image of beings that lived on Mars emerged. Little green men?! Humanoids?! .... Approximately every 26 months the Earth is aligned with Mars and the Sun and located between the Sun and Mars. We say at that moment that Mars is in opposition. In 2020 Mars was in opposition on October 13th. Few days earlier, on October 6th, 2020, Mars was Mars was at its closest approach to Earth. On that day it was approximately 62 million kilometers from Earth. Only on September 15, 2035, Mars will be so close to Earth. Due to the closest approach to Earth three missions were launched in 2020 towards the planet Mars: The China National Space Administration (CNSA) launched on July 23th, 2020, the first Chinese mission to Mars: Tianwen-1 Mission. This mission consisting of an orbiter, a lander and a rover, entered orbit around Mars on February 10th, 2021. The United Arab Emirates Space Agency (UAESA) launched on July 19th, 2020, the first UAE mission to Mars: Hope Mission (Emirates Mars Mission). This mission consisting of an orbiter entered orbit around Mars on February 9th, 2021. NASA launched on July 30th, 2020, the Mars 2020 Perseverance Rover Mission with the first heavier than air by Marcelo de Oliveira Souza The reason, the imagination, and the voice of the heart ... “I asked the land, the sea, the depths and, among animals, the creatures that crawl. I asked the winds that blow and the beings that the sea contains. I asked the heavens, the sun, the moon and the stars and all the creatures around my flesh: My question was the look I was giving them. Its answer was his beauty.” — Saint Augustine (free translation to English)

4 editorial board members • Scott Roberts - Founder and President of Explore Scientific - USA • David Levy - Worldwide famous astronomer, science writer and discoverer of comets and minor planets - USA • Marcelo de Oliveira Souza - DSc. in Physics (Cosmology). University Professor, Educator and Science Communicator. • Hassane Darhmaoui -PhD in Physics from the University of Alberta, in Canada. Associate Professor at the School of Science and Engineering of the Al Akhawayn University in Ifrane (AUI) and Coordinator of the AUI Center for Learning Technologies, founding member and general Secretary of the Arab Astronomical Society (ArAS), founder and national representative of the Universe Awareness (UNAWE) chapter in Morocco, founder and current supervisor and co-director of Al Akhawayn Observatory. Morocco • Andrea Sanchez Saldias - Astronomer, Master in Physics and PhD in Biology (Astrobiology), all degrees obtained at the Universidad de la República. Conducts research in Exobiology and Paleoclimatology on Earth and Mars, Uruguay • Suresh Bhattarai - Science educator, astronomy communicator and researcher in Nepal. National Outreach Coordinator (NOC) for Nepal for 2018-2021 and chairperson at the Nepal Astronomical Society (NASO) • Valentin Grigore - Leading amateur astronomer, specialist in meteor astronomy, astrophotographer, astro-poet, astrojournalist, author, trainer, lighting specialist, dark-sky and ecologist militant, youth worker specialist President of the Romanian Society for Meteors and Astronomy (SARM), National Coordinator for Romania of Astronomers Without Borders (AWB) and producer of the tv show ”Us and the Sky” at Columna TV • Olaynka Fagbemiro - Assistant Chief Scientific Officer with the National Space Research and Development Agency (NASRDA), Founder/National Coordinator of Astronomers Without Borders (AWB) Nigeria, IAU’s National Education Contact (NAEC) for Nigeria and the Public Relations and Education Officer for the African Astronomical Society (AfAS). • Cláudio Moisés Paulo - Prof. Assistant in Astrophysics at Eduardo Mondlane University. Doctor of Astrophysics (University of Witwatersrand, South Africa), Master of Astrophysics (University of the western Cape, South Africa), Honours in Astrophysics and Space Sciences (University of Cape Town, South Africa), and Honours in Physics & Meteorology (Eduardo Mondlane University, Mozambique). • Manoj Pai - One of the most active amateur astronomers in India. Astronomy Club, Ahmedabad, India n n n Marcelo de Oliveira Souza is a physicist with a Master of Science in Physics (General Relativity) at the Universidade Federal Fluminense and a Doctor of Science in Physics (Cosmology) at Universidade Federal do Rio de Janeiro. Since 2004, he has been a professor at the Universidade Estadual do Norte Fluminense and since 2006 he has been the Louis Cruls Astronomy Club General Coordinator. In Brazil, he is the Astronomers Without Borders National Coordinator, the UNAWE program national Coordinator and the Mission X - Lead. He is the author of “Um Passeio pelo Céu,” and, from 2005 until 2013, he presented and wrote the script of the weekly TV program “Um Passeio pelo Céu” about astronomy and astronautics. flight on another planet. The rover Perseverance landed on Mars surface on February 18th, 2021. Schiaparelli and Lowell’s channels have been present in many people’s dreams for years. The reason contradicted the accounts they presented at that time. Even so, many people had their hearts more strongly touched by the possibility of the discovery of a civilization accompanying us in our solitary existence in the Universe. Dream that takes us in the search to develop each day new and more modern equipment for the observation of the Universe. Did Martians exist? Still exist? To answer these questions, will we follow the reason or the voice that comes from our heart? Due to the pandemic caused by the COVID-19 we are living in very hard times. In my country, Brazil, schools are closed since March 2020 and with frequency nonessential trade is often closed and we face moments of great social isolation. Like everything in life it is a passing moment. In this pandemic it was necessary to find new ways to popularize science, and in particular astronomy. Virtual events and creative activities are being carried out by different groups in the world. Our group held several types of events, including a Drive In of Astronomy, the Astrocinema. People participated from inside their cars. It is a way of moving forward even with all the problems and being able to renew hope for better days in the souls of all people. The Universe always inspires and motivates us to move forward. Its answer for us is its beauty, as noted by Saint Augustine. The cover theme of this edition is the Perseverance Rover mission. There are sensational articles written by astronomy researchers and lovers from different regions of our planet. I wish you a pleasant journey while reading this edition of Sky’s Up magazine. I would like to dedicate this edition to the heroes of these new times: health professionals (Doctors, nurses, cleaning staff, physiotherapists, speech therapists, ...). Clear skies for everyone!!!

5 When the COVID-19 pandemic rapidly shuttered the world a year ago, I and so many others found solace in the stars. As stay-athome mandates and other distancing measures physically separated us, the open night sky emerged as a place to connect. Star parties are a staple of amateur astronomy. They are places where beginners can mingle with lifelong astronomers to trade tips, tell stories and share their eyepieces. In some ways, they are the lifeblood of the astronomy hobby, but the pandemic brought all traditional star parties to a sudden halt. To fill the void, the Explore Alliance held its first “Virtual Star Party” on Aug. 4, 2020. This livestream event was inherently different from the star parties we all knew and loved, but it had the most important component – connection. One of the benefits of taking the star party to a virtual platform was the ability to draw in people from everywhere as presenters, hosts and viewers. With this new format, participants were not confined to a single latitude, longitude or hemisphere. The events quickly transitioned to “Global Star Parties,” and our viewership grew astoundingly. In fact, in aggregate, we have reached over a million people from around the world since the weekly broadcast program got underway. John Briggs, a legendary figure in professional and amateur astronomy, compares the short, informal style of the Global Star Party presentations to the evening gatherings at events like Stellafane, where in an evening you can learn from experts and novice alike. The difference is that Stellafane happens once a year in Springfield, Vermont, and the Global Star Party happens once a week from anywhere with an internet connection. Since its inception, the Global Star Party has focused on many different aspects of astronomy from scientific application, to youth in astronomy to women and girls in astronomy. There have also been special edition events with astronomers and astrophotographers across Asia, Europe, and the Americas in both hemispheres. Each Global Star Party has brought the international astronomy community together. Last night, I conducted the 41st Global Star Party. I have served as producer and host for most of the more than 40 events, but I have been lucky enough to persuade many amazing astronomers, scientists and explorers to join in the effort either as contributors or co-hosts or both. The following is just a partial list of the more than 100 amazing people and groups that have participated in and made what the Global Star Party is today: Abigail Bollenbach – Infinity and Beyond Alberto Levy – Astrophotographer Bob Denny – Technologist Cameron Gillis – Astrophotographer Carroll Iorg of the Astronomical League Cesar Brollo - Optica Saracco Christopher Go – Planetary Astrophotographer Chuck Allen of the Astronomical League Chuck Lewis – NASA Engineer – SkyLab David Eicher – Astronomy Magazine Deepti Gautam – Young Astronomer Dr. Alan Stern – PI New Horizons Mission Dr. David Levy – Jarnac Observatory Dr. Marcelo Souza – Cosmologist, Educator Dr. Rosaly Lopes – JPL Scientist Dr. Stella Kafka – Director of the AAVSO Dustin Gibson – OPT Gary Palmer- Gary Palmer Astronomy J. Kelly Beatty – Sky and Telescope Magazine Jack Newton – Astrophotographer Jerry Hubbell – MSRO Astronomer and Scientist John Briggs – Telescope Engineer John Goss of the Astronomical League John Johnson – Nebraska Star Party Kelsey Poor – Novaspace Libby in the Stars – Young Astronomer Mike Weasner – Astrophotographer Molly Wakeling – Astrophotographer Normand Fullum – Optiques Fullum Pekka Hautala - Astrophotograper Pranvera Hyseni – Astronomy Outreach of Kosovo Richard Grace - Astrophotographer Rodrigo Zelada – North Optics Steve Mallia – Ontario Telescope Terry Mann of the Astronomical League The Entire Editorial Staff of Astronomy Magazine The Night Sky Network The Royal Astronomical Society of Canada The Team of the Mark Slade Remote Observatory Tom Meneghini and the Team of Mt. Wilson Observatory Vivian White – Director of the Night Sky Network While it’s noted that you can’t truly replace meeting and interacting with any of these people in person, many around the world would never have the opportunity. The Global Star Party has changed all of that, and that is something worth celebrating. by Scott W. Roberts Astronomy around the world n n n Scott W. Roberts is the founder and president of Explore Scientific in Springdale, Ark. He is an avid amateur astronomer who has spent more than 30 years in the astronomy optics industry.

6 Just one day after the Earth passed its closest point to the Sun in its orbit, its perihelion, the American Astronomical Society was having its annual meeting online, the United States Congress was validating the results of the 2020 national election, and Wendee and I were settling in for a civics lesson about the way the United States Government works. The day did not turn out that way. Shortly before noon, on our television set a news ticker appeared. It announced that two buildings in Library of Congress (LC), the James Madison, and quickly afterwards the Adams and Jefferson buildings, were being evacuated. That news sent a chill through me. The LC is one of the finest libraries in the entire world. It contains more than 170 million books, of which more than thirty are books I wrote entirely or at least a foreword. It also includes all of the more than two hundred “Star Trails” columns I wrote for Sky and Telescope magazine between 1988 and 2008, and dozens more I wrote for other magazines and journals. Only the British library, with over 200 million books, is larger than the Library of Congress. This event was personal for me. A few minutes later, when the entire Capitol complex was stormed, it was personal for all of us. All of us had reactions to this, but in addition to the feelings I shared with most of you, I had an additional feeling — specifically about the library. How many books does it take to make a library? When I was a child in 1963, a teacher gave the best answer I’ve ever heard: “two books.” For me, a library — any library — is every bit as priceless as a dark sky. The wisdom of the ages is contained in each library- from the LC to a child’s collection. I have never gone into a library without feeling better when I exited. The idea that this magnificent collection was threatened that day was terrifying. I have read many books over my lifetime, from The Cat in the Hat to my boxed set of Lord of the the Rings. One small treasure, Jene Lyon’s Golden book Our Sun and the Worlds Around It, began a lifetime of stargazing. That gem, by the way, also lives in the LC. What is more, I have never encountered a really bad book. When an author places her or his thoughts on paper in a book, that book immortalizes those thoughts. I hope that Capitol Hill and the Library of Congress are never threatened again. They belong to we the people, and stand beautifully in Washington, D.C. to govern us, teach us, and encourage us to follow our dreams and reach for the stars. by David Levy Skyward Our priceless treasures COURTESY OF David Levy A look at the main entrance and House side of the U.S. Capitol taken from under the steps on the Senate side. n n n David H Levy is arguably one of the most enthusiastic and famous amateur astronomers of our time. Although he has never taken a class in astronomy, he has written over three dozen books, has written for three astronomy magazines and has appeared on television programs featured on the Discovery and the Science Channels. Among David’s accomplishments are 23 comet discoveries, the most famous being Shoemaker-Levy 9 that collided with Jupiter in 1994, a few hundred shared asteroid discoveries, an Emmy for the documentary Three Minutes to Impact, five honorary doctorates in Science and a PhD which combines astronomy and English Literature. Currently, he is the editor of the web magazine Sky’s Up!, has a monthly column, Skyward, in our local Vail Voice paper. David continues to hunt for comets and asteroids, and lectures worldwide.

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8 By MARCELO DE OLIVEIRA SOUZA Sky’s Up Editor In a region with no artificial lighting, it is possible to perceive a light streak across the sky. Milky path in the firmament. Kuklos galaxies, dairy circle, for the Greeks. Milky Way, for the Romans. Mayu, heavenly river, for the Incas. Tapi’ir Rapé, way of the Tapir, for the Tembé Indians, a Brazilian tribe. For countless years, various civilizations have observed this whitish streak in the night sky. For the ancient civilizations, a mysterious track. Source for legends. In Greek mythology, Hercules was the son of the god Zeus with Alcmena, a mortal. In order to transform Hercules into an immortal, Zeus puts him as a baby to suck the milk from his wife, the goddess Hera, while she slept. Hera wakes up scared away from the baby. The milk that spills from her breasts forms the Milky Way in the sky. The stars Vega, from the constellation of Lira, and Altair, from the constellation of Eagle, are very bright and appear to be separated by the Milky Way. In an ancient Chinese legend, they represent the boy Kengyu and princess Orihime. They were in love. The romance drove them away from their obligations. A fact that irritated Orihime’s father, who decided to distance them so that they could fulfill their tasks. He placed them on opposite sides of the Milky Way. His daughter was very sad about the separation. Sensitized, her father decided that they could meet once a year, on the seventh day of the seventh month of the lunar calendar. On that day the Japanese, from a Chinese tradition, celebrate Tanabata every year. The Festival of the stars. One of the most popular festivals in Japan. Stories ... A brief trip through the world of imagination ... The Milky Way in large cities it is overshadowed by artificial lighting. Today, in dreams, a sea of stars shining smiles and hope. Illuminating life. Showing the path of wisdom. César Lattes, a brilliant Brazilian physicist, always said that “wisdom does not enter into an evil soul at all”. Guarantee for humanity. With the use of telescopes, it was possible to see that the milky way was composed of an enormous number of stars. Galileo Galilei, in 1610, was the pioneer in reporting this observation. The Englishman Thomas Wright in 1750 proposes that the stars, including the Sun, are in the shell, with a finite thickness, of a sphere with a gigantic radius. The center of the sphere was divine. It was a way of imagining why we saw a large concentration of stars only in one strip of the sky. As an alternative model he proposes that the stars, including the Sun, could be in the shell of a ring. The German Imannuel Kant, influenced by Wright’s proposal, proposes that the Milky Way was shaped like a thick disk, like a coin. As we are on the disk, we see a large concentration of stars when we look from the side and a lower concentration of stars when we look up and down. We stop living in a region composed of five more planets, the Sun, and the Moon, and limited by a layer of fixed stars, as imagined by the Greeks, to live around a star, like so many others in our galaxy, the Milky Way. Our address in the Universe. With the development of new observation instruments, more and more accurate information about the Universe was gradually obtained. We envision a new shape for the galaxy in which By DAVID H. LEVY Editorial Board Member Welcome to the second issue of the newly revised Sky’s Up magazine, carefully edited now by Marcelo Souza. Our goal is to inspire our readers to look up at the sky, feel its magic, and enjoy the night. I have been doing this almost every night since I was a child, growing up in Montreal, Canada, in 1960. It is easy. You do not need a Ph.D..; in fact, it helps if you do not have one. All you need are two good eyes, an inquiring mind, and the desire to go out of doors after dark, and look up. Many children– and adults– are afraid of the dark. I have never been; on the contrary I find the onset of night a pleasant and relaxing experience. Going out and looking up, watching the first stars appear, always lessens the cares of the day. And as more stars appear, these cares vanish altogether and I am left with the joy of wondering what is up there. Has anything changed since last night? Any surprises I am not expecting? This is the magic that the poetry of the night sky offers every evening. As you read this magazine, I hope it will offer you the same. Reach for the stars! a guide to the sky The Milky Way: Our address in the Universe

9 a guide to the sky we live. A barred spiral galaxy... In December 1924 at the joint meeting of the American Astronomical Society and the American Association for the Advancement of Science, Edwin Hubble announced that Andromeda was another galaxy ... Our galaxy was not unique. Each day we are a physically smaller point in the model of the Universe that humanity has been building. Limited, like our existence. It is a unique experience to observe the sky in a region with little artificial lighting. Seeing the splendor of the Milky Way in the firmament is an unforgettable opportunity!!! A moment for reflection on life and its mysteries. This view shows several of the ALMA antennas and the central regions of the Milky Way above. In this wide field view, the zodiacal light is seen upper right and at lower left Mars is seen. Saturn is a bit higher in the sky towards the centre of the image. The image was taken during the European Southern Observatory Ultra HD (UHD) Expedition. IMAGE CREDIT: ESO/B. Tafreshi (twanight.org)

10 Mercury Mercury will be visible in May for a short period after the Sunset in the Constellation of Taurus. For few days it will not be possible to see Mercury and the planet will return to be visible before the sunrise in June (the best period to see Mercury will be the last week of June) in the Constellation of Taurus. In July Mercury will be visible before the sunrise. In the first week of July Mercury will be moving from the Constellation of Taurus to the Constellation of Gemini. Venus Venus will be visible after the Sunset, for a short period, in June and July. In this period Venus will be moving from the Constellation of Gemini to the Constellation of Leo, passing by the Constellation of Cancer. Saturn Saturn will be visible before the Sunrise and after midnight in April and May, each day will be visible earlier. In June and July, the planet of the rings will be visible from before midnight until the sunrise, each day be seen earlier. Saturn is in the Constellation of Capricornus. Mars Mars will be visible in the evening sky from April to July, each day the red planet will be seen for a shorter period after the sunset. Mars, in April is in the Constellation of Taurus moving to the Constellation of Gemini, in May will be in the constellation of Gemini, in most of June will be in the Constellation of Cancer and in the first days and in most of July will be in the constellation of Leo. Jupiter Jupiter will be visible before the Sunrise and after midnight in April and May, each day will be visible earlier. In June and July, the giant planet will be visible from before midnight until the sunrise, each day be seen earlier. In April Jupiter is moving from the Constellation of Capricornus to the Constellation of Aquarius. From May to July Jupiter will be in the Constellation of Aquarius. Looking for resources? An excellent reference about the observation of the 5 planets visible to the naked eye is the homepage “The Naked Eye Planets in the Night Sky” produced by Martin J. Powell. This homepage has detailed information about the position and visibility of each of the planets of the Solar System. To access “The Naked Eye Planets”, click here. planetary positions COURTESY OF Software Stellarium

11 a guide to the sky (All times in Universal Time – UT) April – Global Astronomy Month 6 — Conjunction of the Moon and Saturn 7 — Conjunction of the Moon and Jupiter 10 — Mercury at greatest western elongation at 17:00h 12 — New Moon at 3:30h a.m. 16-18 — 13th International Meeting of Astronomy and Astronautics – doity.com. br/13imaa 17 — Conjunction of the Moon and Mars 17 — Lunar occultation of Mars (visible only in part of Asia) 18 — Mercury in superior conjunction 20 — Moon First Quarter at 7:58h a.m. 21-22 — Peak of the Lyrid Meteor Shower 27 — Full Moon at 4:31h a.m. with the Moon at perigee May 3 — Moon Last Quarter at 8:50h p.m. 3 — Conjunction of the Moon and Saturn 4 — Conjunction of the Moon and Jupiter 4-5 — Peak of the Eta Aquarid Meteor Shower 11 — New Moon at 7:59h p.m. 12 — Conjunction of the Moon and Venus 13 — Conjunction of the Moon and Mercury 17 — Mercury at greatest elongation east 19 — Moon First Quarter at 8:12h p.m. 26 — Full Moon at 12:13h p.m. 26 — Total Lunar Eclipse - visible Australia, parts of the western US, western South America, or in South-East Asia. Greatest eclipse at 11:18h. 29 — Conjunction of Venus and Mercury 30 — Conjunction of the Moon and Saturn June 1 — Conjunction of the Moon and Jupiter 2 — Moon Last Quarter at 8:24h a.m. 10 — New Moon at 11:52h a.m. 10 — Annular Solar Eclipse - visible from parts of Russia, Greenland, and northern Canada. Greatest eclipse at 10:41h. 10 — Mercury in inferior conjunction 12 — Conjunction of the Moon and Venus 13 — Conjunction of the Moon and Mars 18 — Moon First Quarter at 4:54h a.m. 21 — June Solstice at 3:32h a.m. 24 — Full Moon at 7:39h a.m. 27 — Conjunction of the Moon and Saturn 28 — Conjunction of the Moon and Jupiter July 1 — Moon Last Quarter at 10:10h p.m. 8 — Conjunction of the Moon and Mercury 10 — New Moon at 2:16h a.m. 12 — Conjunction of the Moon and Venus 13 — Conjunction of Venus and Mars 17 — Moon First Quarter at 11:10h a.m. 24 — Full Moon at 3:36h a.m. 24 — Conjunction of the Moon and Saturn 25 — Conjunction of the Moon and Jupiter 28-29 — Peak of the Delta Aquarid Meteor Shower 31 — Moon Last Quarter at 2:15h p.m. upcoming events: By MARCELO DE OLIVEIRA SOUZA Sky’s Up Editor In a very distant past people noticed that there was a variation in the size and direction of an object’s shadow during the day. Following and analyzing these variations it was possible to build the first instrument to determine the hours during the day: The Sundial. The main idea of sundials is to associate the variation of the shadow of an object, which is called a Gnome, with the hours of the day. Today there are a large number of sundial models. One model stands out because it uses people like the Gnomon. This sundial with human interaction is called the Analemmatic Sundial. This model of sundial has an ellipse-shaped hour scale and in the center of the ellipse another vertical scale with the months of the year. In the Analemmatic Sundial, the Gnomon (the object that will cast its shadow to mark the time) is anyone who will position himself on the scale that is in the center of the ellipse. It is an excellent sundial to build in public places. I, Marlon Pessanha and Jorge André Ferreira Machado developed a free App for Android that will allow anyone to build an Analemmatic Sundial. To download the app, click here. The Analemmatic Sundial is an excellent educational tool to talk about the tilt of the Earth’s axis, the annual movement of the Earth around the Sun and the apparent movement of the Sun. Android app helps users build analemmatic sundial

12 By Mahdi Rokni Guest Contributor There is no man who has been in Iran and did not experience gathering together and enjoying the moment; memorable memories are inextricably linked to being together in Persian language countries. There are several reasons and ceremonies in different countries that gather people together such as New Year holiday, Christmas, Thanksgiving and Halloween. However, the reason of yearly ceremonies in Persian lands is slightly different. Astronomy has a great key role in these ceremonies. All the scientific facts about Earth rotation around the Sun and its movements that surprised astronomers have been a main reason of Persians’ ancient celebrations. In Persian lands, Yalda night or Cheleh night is an ancient Persian ceremony based on Earth’s position at winter solstice. In winter solstice Earth places in the most southerly declination (-23.4°) to the celestial equator. By winter solstice, winter and summer begin in northern and southern hemispheres of Earth. This interesting symmetry results in two completely different and contradictory season in both hemispheres. The farther you are away from the equator the night A night to respect the light Yalda COURTESY Watermelon and pomegranate are symbols of the sun because of their red color and they are inseparable parts of Yalda celebrations.

13 of winter solstice (summer solstice in southern hemisphere) would be longer. Even in latitudes near 90° in both hemispheres the Sun would rise after 24 hours. The day after the winter solstice marks the beginning of lengthening days, leading up to the summer solstice in June. In the Southern Hemisphere, the opposite is true; people will experience their longest day and shortest night. An interesting point is that this night in western Asia countries whose language is Persian and located between 25° to 45° latitude is just a few seconds longer than other nights; So this difference is not tangible. However they have recognized this difference from ancient time even before Christ and have mentioned solstices and equinoxes in their calendar like Egyptians, Chinese, and Greeks. Such astronomical events have a great role in their lives. They performed religious rites and special fiestas on that day. According to the beliefs of Persians, after winter solstice in the beginning of winter; days start getting longer eventually till the celebration of Persian new year in spring equinox, so they consider this time as a good omen and they have been celebrating this night with special traditions for centuries. they call this night ‘’YALDA’’ and the ceremony is called ‘’SHAB-EYALDA’’ which means Yalda night. Yalda means BIRTH. Iranian believe that IZAD (GOD) will shine more sunshine on this land, people celebrate the special night of the birth of light and sun. Although this night has been through lots of changes over centuries; its thematic principles still exist among Persians families and it never fades away. The most important part of SHAB-EYALDA is gathering and spending time with each other. Iranian love to have fun and enjoy this beautiful night with their loved ones. They provide their best food and fruit like watermelon and pomegranate for this night. Watermelon and pomegranate are symbols of the sun because of their red color and they are still inseparable parts of this night. The food served at this night varies among different Persians regions, it depends on the agricultural products and geographical location in Iran or in countries such as Afghanistan, Tajikistan and Azerbaijan. Another beautiful and important tradition in SHAB-E-YALDA that has been seen for centuries is honoring the poets and elders of Persian literature. SHA’AH NA’AME is one of the most important works of epic poetry which is about ancient myth and beliefs of Persian nation. At Yalda night when the elder of family reads the SHA’AHNA’AMEH and they call the act of reading SHA’AHN’AAME, SHA’AHNA’AMEHKHA’ANI. the stories pf SHA’AHNA’AME are very popular among Iranians, especially children. Furthermore HAFEZ KHANI (reading HAFEZ’S poems) has very special place among families at this night. HAFEZ is a famous Iranian poet whose poems are very popular not only in Iran but also in the whole world. Over centuries and changes, Persians perform Yalda night’s traditions with prosperity and joy. It has become one of the oldest ceremonies in the world along with Christmas and New Year celebrations. COURTESY The Earth and The Sun positions at December and June solstice COURTESY Iranian historical motifs indicates the antiquity of ancient rituals and celebrations in this region.

14 wonderful universe By MARCELO DE OLIVEIRA SOUZA Sky’s Up Editor The exploration of Mars is one of humanity’s greatest dreams. The first spacecraft that successfully entered Mars orbit was the American spacecraft Mariner 4 on July 14, 1965. It was the first time a spacecraft sent images of Mars back to Earth. From 1960 to 1973 the Soviet Union launched 15 missions to Mars. Of that total, only 5 missions, Mars 2 and Mars 3 in 1971 and Mars 5, 6 and 7 in 1973, successfully entered Mars orbit. The missions Mars 2 and Mars 3 were composed of an orbiter, a lander, and a rover. On November 27th, 1971, happened the first impact of a lander on Mars surface, during a Mars 2 mission failed attempt. On December 2nd, 1971, happened the first landing of a lander developed by humans on Mars. The lander of the Mars 3 mission had a soft landing and sent a partial image back to Earth but COURTESY OF NASA/JPL This color picture of Mars was taken July 21, 1976, — the day following Viking l’s successful landing on the planet. The local time on Mars is approximately noon. The view is southeast from the Viking. Orange-red surface materials cover most of the surface, apparently forming a thin veneer over darker bedrock exposed in patches, as in the lower right. The reddish surface materials may be limonite (hydrated ferric oxide). Such weathering products form on Earth in the presence of water and an oxidizing atmosphere. The sky has a reddish cast, probably due to scattering and reflection from reddish sediment suspended in the lower atmosphere. COURTESY OF NASA Viking Lander 2 Camera 2 FROST (Low Resolution Color) Sol 1028, 1030 and 1050 between 11:34 and 12: Landers & rovers have brought us closer to Mars Capturing the Red Planet

wonderful universe worked only for approximately 100 seconds. The lander carried a rover. It was the first time a rover landed on Mars. The rover didn’t send any information back to Earth. Everything changed in 1976!!! This is the year that the probes Viking 1 and Viking 2 landed on Mars!!! I still remember the moment when I saw the images of the surface of Mars sent by the Viking probes. I saw them in the book Cosmos written by Carl Sagan. They were the first images of the surface of another planet obtained by a probe landed on the planet. It was wonderful!!! The Viking 1 landed on July 20th, 1976 and the Viking 2 landed on September 3rd, 1976. Each mission was also composed by an orbiter. After the success of Vikings 1 and 2, many missions were launched for Mars. We will focus only on the missions that landed probes and rovers on the red planet. The rover Sojourner landed on Mars on July 4th, 1997. It was sent to Mars by the NASA’s Pathfinder Mission. Sojourner was the first rover to operate on another planet. The lander Pathfinder sent great images back to Earth. The next rovers sent to Mars by NASA were the twins Spirit and Opportunity. They landed on Mars in 2004: Spirit on January, 4th and Opportunity COURTESY OF NASA/JPL The first color picture taken by Viking 2 on the Martian surface shows a rocky reddish surface much like that seen by Viking 1 more than 4000 miles away. The planned location for the collection of soil for on-board analysis is seen in the lower part of the photo. Sojourner takes its Alpha Particle X-ray Spectrometer measurement of the Yogi Rock. COURTESY OF NASA / JPL 15

on January 24th. Both explored a large region of Mars near the lander site. The rover Spirit had traveled a distance of 7.73 km and sent data and images until March 22th, 2010!!! The rover Opportunity had traveled 45.16 km and sent data and/or images until June 10th, 2018!!! On May 25th, 2018, the NASA’s probe Phoenix landed on the surface of Mars on May 25, 2008. The main objective of the mission is to research the history of water on Mars. The rover Curiosity is one of the most fantastic rovers ever sent to Mars!!! It landed on Mars on August 6, 2012. It has the size of a car!!! Curiosity has the following dimensions: 2.9 m long by 2.7 m wide by 2.2 m in height. It has a mass of 899 kg. Curiosity is still working. In this picture two Jet Propulsion Laboratory engineers stand with three vehicles, providing a size comparison of three generations of Mars rovers. The new NASA’s rover Perseverance has almost the same size of the rover Curiosity. The rover Curiosity since its land is sending fantastic data and images back to Earth. On November 26th, 2018, the probe InSight landed on Mars. The mission InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) has the main objective to study the deep interior of the planet Mars. From now we have a new stage in the history of the Mars exploration with the land of the NASA’s rover Perseverance with the mini helicopter Ingenuity and with the near land of the Chinese rover from the Tianwen-1 mission. 16 wonderful universe COURTESY OF NASA/JPL Above and below, these images of the Mars Pathfinder landing site was taken by camera on the lander known as IMP (Imager for Mars Pathfinder). COURTESY OF NASA/JPL/Cornell This panoramic image mosaic from the Mars Exploration Rover Spirit panoramic camera, shows the rover’s destination toward the hills nicknamed the “Columbia Hills,” on the right. Dark drift material can be seen in the image center. This image was taken on sols 68 and 69 of Spirit’s mission (March 12 and 13, 2004) from the location the rover first reached on the western rim of the crater.

wonderful universe 17 COURTESY OF NASA/JPL/ASU/Cornell Above, this view in approximately true color reveals details in an impact crater informally named “Fram” in the Meridian Planum region of Mars. The picture is a mosaic of frames taken by the panoramic camera on NASA’s Mars Exploration Rover Opportunity during the rover’s 88th martian day on Mars, on April 23, 2004. The crater spans about 8 meters (26 feet) in diameter. Opportunity paused beside it while traveling from the rover’s landing site toward a larger crater farther east. This view combines images taken using three of the camera’s filters for different wavelengths of light: 750 nanometers, 530 nanometers and 430 nanometers. Below, Opportunity’s view from the top of Cape Tribulation on the rim of Endeavour Crater on Jan. 22, 2015. COURTESY OF NASA/JPL-Caltech/University of Arizona/Texas A&M University A thin layer of water frost is visible on the ground around NASA’s Phoenix Mars Lander in this image taken by the Surface Stereo Imager at 6 a.m. on Sol 79 (August 14, 2008), the 79th Martian day after landing. The frost began to disappear shortly after 6 a.m. as the sun rose on the Phoenix landing site. COURTESY OF NASA/JPL-Caltech/University of Arizona This image, released on Memorial Day, May 26, 2008, shows the American flag and a mini-DVD on the Phoenix’s deck, which is about 3 ft. above the Martian surface. The mini-DVD from the Planetary Society contains a message to future Martian explorers, science fiction stories and art inspired by the Red Planet, and the names of more than a quarter million earthlings.

wonderful universe COURTESY OF NASA Two spacecraft engineers stand with a group of vehicles providing a comparison of three generations of Mars rovers developed at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. The setting is JPL’s Mars Yard testing area. Front and center is the flight spare for the first Mars rover, Sojourner, which landed on Mars in 1997 as part of the Mars Pathfinder Project. On the left is a Mars Exploration Rover Project test rover that is a working sibling to Spirit and Opportunity, which landed on Mars in 2004. On the right is a Mars Science Laboratory test rover the size of that project’s Mars rover, Curiosity, which landed on Mars in 2012. Sojourner and its flight spare, named Marie Curie, are 2 feet (65 centimeters) long. The Mars Exploration Rover Project’s rover, including the “Surface System Test Bed” rover in this photo, are 5.2 feet (1.6 meters) long. The Mars Science Laboratory Project’s Curiosity rover and “Vehicle System Test Bed” rover, on the right, are 10 feet (3 meters) long. The engineers are JPL’s Matt Robinson, left, and Wesley Kuykendall. Right, this is NASA InSight’s second full selfie on Mars. Since taking its first selfie, the lander has removed its heat probe and seismometer from its deck, placing them on the Martian surface; a thin coating of dust now covers the spacecraft as well. COURTESY OF NASA/JPL-Caltech 18

wonderful universe Left, this self-portrait of NASA’s Curiosity Mars rover shows the vehicle at “Namib Dune,” where the rover’s activities included scuffing into the dune with a wheel and scooping samples of sand for laboratory analysis. The scene combines 57 images taken on Jan. 19, 2016, during the 1,228th Martian day, or sol, of Curiosity’s work on Mars. The camera used for this is the Mars Hand Lens Imager (MAHLI) at the end of the rover’s robotic arm. Below, this composite image looking toward the higher regions of Mount Sharp was taken on September 9, 2015, by NASA’s Curiosity rover. In the foreground — about 3 kilometers from the rover — is a long ridge teeming with hematite, an iron oxide. Just beyond is an undulating plain rich in clay minerals. And just beyond that are a multitude of rounded buttes, all high in sulfate minerals. The changing mineralogy in these layers of Mount Sharp suggests a changing environment in early Mars, though all involve exposure to water billions of years ago. Further back in the image are striking, light-toned cliffs in rock that may have formed in drier times and now are heavily eroded by winds. COURTESY OF NASA/JPL-Caltech/MSSS 19

20 By ANDREA SÁNCHEZ SALDIAS Guest Contributor Mars has aroused the interest of mankind since immemorial times, probably because its reddish coloration is noticeable in the sky. Ancient civilizations named it in honor of different deities that were associated with its reddish color, the color of blood and war: for the Greeks it was Ares and for the Romans Mars. Aristotle, in the 4th century BC, observed an occultation of Mars by the Moon, thus deducing that Mars was further away than our natural satellite. Tycho Brahe made, between 1580 and 1600, the most accurate observations of the position of Mars of this period and Galileo Galilei in 1610 observed it for the first time through his telescope. In 1877 the Italian astronomer Giovanni Schiaparelli observed structures on the surface of Mars that he called “canali” in his native Italian language. This term was translated into English as ‘channels’, which led to thinking about artificial structures. In 1894, the American astronomer Percival Lowell built an observatory for the systematic observation of the red planet and, influenced by Schiaparelli’s observations, came to develop hypotheses that explained these channels as great works of extraterrestrial engineering destined to bring water from the poles to the Mars 2020 mission takes search for life to next level COURTESY OF Meyers Konversations-Lexikon (German encyclopaedia), 1888 Schiaparelli’s map of the Martian surface. With Perseverance & Ingenuity, Right, NASA’s Ingenuity Mars helicopter is seen here in a close-up taken by Mastcam-Z, a pair of zoomable cameras aboard the Perseverance rover. This image was taken on April 5, 2021, the 45th Martian day, or sol, of the mission. The mosaic is not white balanced but is instead displayed in a preliminary calibrated version of a natural color composite, approximately simulating the colors of the scene that we would see if we were there viewing it ourselves. Credit: NASA/JPL-Caltech/ASU

21 equator to sustain an endangered Martian civilization. It is paradoxical that Lowell considered a civilization dying out on Mars and a century later it is considered an option for Humanity, considering that our planet is running out of resources and going through crises such as climate change, among others. Mars is the fourth planet in distance from the Sun, with an intermediate size between our Moon and the planet Venus. Its average radius is 3396 km and its mass is one tenth of the earth’s mass. There are similarities between both planets, they both have polar caps and the current value of the axis of rotation of Mars has a value very close to that of Earth (of the order of 23.5o) .This determines the existence of seasons, with the Above, NASA’s Perseverance Mars rover took this selfie with the Ingenuity helicopter, seen here about 3.9 meters from the rover, using the WATSON camera on its robotic arm on April 6, 2021, the 46th Martian day, or sol, of the mission. Left, Crater Jezero is seen in this Image taken from the Mars Express orbiter. COURTESY OF NASA/JPL-Caltech/MSSS ESA / DLR / FU-Berlin

22 exception that the Earth’s axis of rotation remains stable due to the gravitational influence of the Moon, while the Martian axis presents a chaotic movement, reaching tilt values of more than 60o. For this reason, modeling the planet’s past climate is a very complex process. However, evidence from different space missions indicates that about 3.5 billion years ago, the atmosphere was denser and the planet was warmer. Under these conditions, there was surely liquid water on the surface, an indispensable condition for the origin of life, as we know it. If we think that life on our planet began approximately 3.8 billion years ago, over a considerable window of time both planets could have harbored life forms, such as microorganisms. Perhaps life arose independently on both planets or perhaps there was an exchange of biological structures between them. On Earth, with more stable climatic conditions, life prospered giving rise to increasingly complex structures, but what could have happened on Mars? Perhaps organisms formed and due to the fact that the environment radically changed they became extinct. Maybe they adapted and are still there. Obtaining data to answer those questions is the challenge of the Perseverance mission. As a precedent we have the Viking program, which in 1971 sent two probes to Mars that were the first American missions to land on the planet. These probes had the ability to take soil samples and analyze them for signs of biological activity. The results were not conclusive and it was even argued that the experiments that tested positive could be related to contamination of the probes on Earth. In August 2012, the Curiosity mission landed in the Gale crater, on the surface of Mars. From previous images, the scientific community agreed on the past existence of liquid water on the surface and, therefore, the existence of a denser atmosphere than the current one. The rocky sediment analysis of the crater where the Rover landed had two relevant results: 1 - the existence of a lake of liquid water 3.5 billion years ago 2 - the existence of organic molecules in that ancient lake. The concentration of carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur, key elements for life, was measured. If to this we add the record of high seasonal values of methane (indirect indicator of biological activity) the past or current existence of simple living organisms, such as bacteria, is a feasible hypothesis. On February 18 of this year, the Rover Perseverance landed on Mars with four goals: 1) identify habitable environments for life in the planet’s past 2) look for signs of microbial life in those environments 3) take samples of surface and Martian rocks 4) try to produce oxygen on Mars The site chosen for the landing was the Jezero crater, which is located in a dry river delta type structure. The technological challenge that represents the descent of a rover without accidents on Mars, increases when the size and mass are large. Perseverance has a small car size and weighs 1050 kg. Just like Curiosity, the descent implies that 13 km from the surface a parachute opens up, which is connected to the descent vehicle that supports the rover through special stretches. One of the novelties of this mission is the Terrain-Relative Navigation (TRN) navigation system, which allows you to contrast the images that Perseverance chambers take during the descent and to contrast them with images from other missions. This technology makes it possible to avoid errors in relation to the landing site and, if irregular reliefs are identified, avoid them. Another novelty is the small Ingenuity helicopter, the first device to fly in the atmosphere of another planet. It can travel up to 300 meters COURTESY OF NASA/JPL-Caltech In this image taken on May 20, 2020 at the Kennedy Space Center, engineers and technicians insert 39 sample tubes into the belly of the rover. Each tube is sheathed in a gold-colored cylindrical enclosure to protect it from contamination. Perseverance rover will carry 43 sample tubes to the Red Planet’s Jezero Crater.

23 per flight and take high resolution images. From the point of view of astrobiology, there are two relevant experiments and both will be carried out for the first time in the history of the exploration of Mars. First, the rocks and Martian soil will be drilled, and the samples obtained will be stored in 43 different tubes. The mechanism is similar to that used to study the records of hundreds of thousands of years of climate in ice holes in Antarctica. Samples from Mars will be brought to Earth by future missions, between 2025 and 2030. Not all tubes that this mission will use will have samples from Mars. Four of them will function as “witness containers”, that is to say that what is found in them will be due to contamination on Earth. Any other findings in the samples from the other vessels will be due exclusively to Mars. Furthermore, we know that the Martian atmosphere is basically made up of carbon dioxide, so humans who travel to Mars will not be able to breathe freely. The low amount of atmospheric oxygen determines that the planet does not have an ozone layer that protects it from radiation. The MOXIE device (Mars Oxygen In situ Experiment) will perform the experiment of taking CO2 from the atmosphere and producing oxygen by electrolysis. It has a power of 300 Watt and is capable of producing 9 grams of oxygen per hour. It is a small device that will perform intermittent experiments during mission time. If successful, later missions will carry larger and more powerful devices capable of generating more oxygen. If all other experiments related to life on Mars give negative results and MOXIE is successful, we will at least have the consolation of having taken the first step to make Mars habitable for humans in the future. COURTESY OF NASA/JPL-Caltech This image was captured while NASA’s Perseverance rover drove on Mars for the first time on March 4, 2021. One of Perseverance’s Hazard Avoidance Cameras (Hazcams) captured this image as the rover completed a short traverse and turn from its landing site in Jezero Crater. A key objective for Perseverance’s mission on Mars is astrobiology, and it will be the first mission to collect and cache Martian rock and regolith (broken rock and dust).

24 A window to the Sun By DEBASIS SARKAR Guest Contributor “Where are we from?” The obvious answer is the SUN. An energy belching fireball. The only star that we can see as a DISH. All other stars appear to us just as DOTS, even through the largest possible telescope. The Sun has always fascinated man as it gives us light to see everything. But the fireball always keeps itself hidden behind its own dazzling curtain. A Hydrogen-Alpha Telescope or in short “H-Alpha telescope” is a tool to cross that barrier and study the Sun. This high tech, expensive, super special tool is no more a monopoly of professional experts in big solar observatories. Advent of technology has brought it to the arena of common enthusiasts. Using materials like soot glass, welder glass or solar image projection remained old and popular ways to cut down the extremely high intensity of the Sun for visual observation. But all these show the Sun as a flat dish- without much of its surface details. But H Alpha systems can show us many solar surface features. Those include solar prominences or filaments which are large, bright features extending outward from the Sun’s surface into the Sun’s hot outer atmosphere, Corona. There are a few other systems that do similar work. But the H Alpha system is the best known among them. Beside different solar features, these specialized Sun Hydrogen-Alpha systems are key to studying our star COURTESY OF Debasis Sarkar and Janmejoy Sarkar. (Sky Watchers Association of North Bengal) Sun through H-Alpha

25 viewing systems also give stunning views of solar eclipses. Shooting this giant blazing ball during transits of inner planets or the International Space Station over its face is also a fascinating challenge for serious sky enthusiasts. What is the colour of sunlight? The Sun releases a huge bundle of electromagnetic waves of a wide range of wave lengths. Out of this complete range or spectrum, only a tiny portion from red to violet comes within our visual perception. While red has its wavelength of 700 Nanometer or 7000 Angstroms (Å = 1/,00,00,000 millimeter), that of violet is 400 nm or 4000 Å. Thus, when this almost white incidental is broken down using a prism, it gives an output as a wide band of different colours from red to violet. This is a smaller portion of the full spectrum of visible light in different colours. Each colour in that spectrum has its own distinctive wavelength. How bright is the Sun? It is absolutely too bright to be seen. The first objective in observing is to reduce the intensity of sunlight. This is done using Sun filters that can bring down the intensity to 1/100,000 times. At this diminished intensity, the Sun appears no brighter than the Full Moon. As all the colours of sunlight get almost equally attenuated with these filters, we find the Sun as a near white dish. But it appears almost flat and featureless as details of the Sun’s COURTESY OF Debasis Sarkar and Janmejoy Sarkar. (Sky Watchers Association of North Bengal) Above, filament and prominence; below, spectrum of visible light

26 dynamic top surface “chromosphere” get washed out due to the much brighter underlying “photosphere” layer. Here comes the role of the H-Alpha system. What is H-Alpha? As we know, following particle physics rules, every element influences electromagnetic waves of a specific wavelength thus a specific portion of spectrum. If we break and study sunlight into a spectrum through a spectroscope, we find many definite dark lines in the multicolour band due to the absence of a few particular colours or lights of particular wavelengths in it. These dark lines are caused by elements that absorb the lights of those particular wavelengths. The most prominent one among them is caused by absorption or influence of hydrogen. That portion of the spectrum at the wavelength of 6562.8 Angstroms is commonly known as H-Alpha. The Sun’s top surface or chromosphere greatly influences this particular portion of spectrum as it is actually a layer of glowing hydrogen gas. Naturally, if we can see Sun only through the H-Alpha portion of spectrum by eliminating all other lights, we will be able to ‘see’ disturbances, influences or details of the chromosphere. But to do that, instead of simple filtering we need a system that at first can attenuate sunlight to a safe level, then block all colours of spectrum while allowing a very narrow portion or band of that only to pass. To work properly, this bandpass needs to be only 0.7 Å wide centered at Hydrogen Alpha spectral line (6562.8 Å). A time tasted method of doing this is by using a spectrohelioscope. But that is too complicated a system to be used by a common enthusiasts. The other and more common method is an H-Alpha system that allows a band pass of 0.5 to 1.0 Å centering at 6562.8 Å. What are the main sections of an H Alpha system? Energy Reduction Filter (ERF) Fabry-Perot Etalon Blocking filter(BF) COURTESY OF Debasis Sarkar and Janmejoy Sarkar. (Sky Watchers Association of North Bengal) Solar transit of International Space Station in H-Alpha (India’s first H-Alpha ISS Solar Transit image)

27 What is an Energy Reduction Filter? ERF is the first part of an H-Alpha system. It cuts down the intensity of light almost equally for the entire spectrum. This filter is usually placed in front of a refractor telescope of aperture ratio f/10 or higher. What is Fabry-Perot Etalon? Named after its inventors Charles Fabry and Alfred Perot, this special kind of arrangement of two optical discs is the heart of this system. It allows only specific sections of spectrum to pass through. Etalon is a stack of two planeparallel optical surfaces with a tiny space in between. With proper and careful placing, this stack can cause interference of light that comes on it. And then it gives out a series of narrow bandwidth (Near 1 Å) spikes of light components in its output. One of these spikes comes with 6562.8 Å wavelength H-Alpha line at its center. But this output is not yet ready for observation as it is still a mix of many light components of different frequencies from the full spectrum. What is blocking filter? This third item is a semi narrow bandpass filter that allows small portion of spectrum around H-Alpha line while blocking all others. When the series of spikes coming out of Etalon is passed through this BF, it blocks all but allows one spike only with 6562.8 Å wavelength at its center. This final narrow band light coming out the BF carries the sharp signature of the hydrogen rich chromosphere or solar surface. What is 2nd Stack of Etalon? To make the image further sharper, even narrower bandwidth is needed. To ensure that, a second stack of etalon is added to the system. When properly tuned, the second etalon marginally cuts down the bandpass allowed by the first one. With a carefully maintained and tuned double etalon system, we can have a COURTESY OF Debasis Sarkar Above, diagram of H-Alpha telescope system; left, sunspot COURTESY OF Debasis Sarkar and Janmejoy Sarkar. (Sky Watchers Association of North Bengal)

28 narrower bandpass of even 0.5 Å. Understandably, images formed through an H-Alpha system is essentially monochromatic. Only one colour is there which is predominantly red because of its frequency 6562.8 Å, very close to that of red (7000 Å). Thus, to make them visually pleasing the images are usually false colored instead of keeping monochromatic or black and white. How to use H-Alpha? Basic usage of this goes like common refractor telescopes that can be used for either live viewing or photographing. But tuning an H alpha system is a tedious job that demands deep patience. Attachment of a second etalon sharpens the image, but at the cost of brightness and by making it more complicated to handle. Eventually, viewing becomes tougher with an H-Alpha system with a second stack of etalon. As it is with all other optics, the quick movement of the Sun within the field of vision is a major hurdle. A properly polar aligned RA axis motorized mount can keep the system in sync with Earth’s movement and thus freeze the Sun’s movement in the viewing field. How to do photography with H-Alpha? There are different techniques to attach a camera to an H-Alpha system. It can be “prime focus” style where the eyepiece of H-Alpha system and camera lens are not used. The main objective of the system works as the camera lens while camera body takes the photo. Or “afocal” style where the image formed by the objective is thrown by the eyepiece on the camera lens. Eyepiece projection is also common to “project” the image formed by objective through the eyepiece directly on film or electronic image sensing panel inside the camera without its own lens. But whatever be the attachment pattern, filament and other surface details demand grossly different exposure settings of an H-Alpha camera set-up. Thus, multiple shots with different properly calculated exposures are taken. Then specialized image post processing techniques are adopted to blend those images to develop an image with proper replication of surface details consisting of different features. Is it available? Now many companies offer H-Alpha systems at affordable price ranging from USD 600 to USD 4000. But high import duty or shipping cost are factors to escalate its price in India. As it is with almost everything else, ease of using them or other features of different models of different brands vary with the price. And so for the output quality too. Here, in this article, images taken with moderately sized system only have been included. COURTESY OF Debasis Sarkar and Janmejoy Sarkar. (Sky Watchers Association of North Bengal) Solar surface features and size of solar system objects against them. Fascinating solar features observed through H-Alpha Prominence: Large, bright, gaseous tongues extending outward from the Sun’s surface. Anchored to the Sun’s surface in the photosphere, prominences extend outwards into the Sun’s corona. Solar filaments: These are dark lines or curves on solar surface. Filaments are actually prominences seen from different perspective. These appear dark over the background of the much brighter solar surface. Sunspots: Dark spots on the solar surface. These are cooler areas compared to its surrounding. Solar Flares: These are sudden explosions of energy due to tangling, crossing or reorganizing of magnetic field lines near sunspots. Solar granulation: Grainy feature visible on the surface of the Sun. Thermal currents in the thermal columns causes formation of granulation.

29 LIGA ASTRONÓMICA Más de 70 programas de observación Reflector: revista trimestral Premios de Astronomía Programa del telescopio de la biblioteca Horkheimer Youth Awards ALCON Convención Nacional ¡NUEVO! ¡NUEVO! Williamina Fleming Imaging Award www.astroleague.org para ti! ¡La Liga está aquí Producido por la Liga Astronómica SERVICIO DE RESERVA Duplicación permitida y formentada para toda distribución gratuita Descargas de alcance Premios Juveniles Horkheimer

30 By COLIN HENSHAW Guest Contributor In centuries past there wasn’t any electric lighting. The only lighting that was available was provided by oil lamps and candles, which in some communities were used to illuminate streets. The lighting was only provided on a must-need basis and was relatively unobtrusive. The astronomers of the day would actually observe from town centres, as evidenced by the Rundetaarn (the Round Tower) in Copenhagen, Denmark1. The Royal Greenwich Observatory was located in Greenwich, which at the time was a village outside London. The 19th century brought gas street lighting, which again was relatively unobtrusive, and this persisted in some areas right into the 1960s. However, toward the end of the century advances were made in electric lighting technology, and this was used to replace the gas lighting that was used to light streets. Even so it was still relatively unobtrusive, and was confined mainly to urban areas. However, it was beginning to affect astronomers, and staff at the Royal Greenwich Observatory found they could no longer function effectively from the increasingly light polluted skies of London. They felt obligated to move and relocated to Herstmonceux in rural Sussex, not far from the coastal resort of Eastbourne. The Godlee Observatory, located in the old University of Manchester Institute of Science and Technology, in the centre of Manchester, was built at the turn of the 20th century, and is the base for Manchester Astronomical Society. It would have given some fine views of the night sky. It is still in use, but light pollution from the city renders it useful only for observing the Moon and the brighter planets. In the latter half of the 20th century, street lighting began to expand, and by the late 1960s, after the widespread introduction of sodium lighting, it became so widespread that the cloud deck above cities began to glow orange. It was obvious now that there was a serious environmental problem. Astronomers, however, are a placid group of people and not given to political agitation, so for many years they suffered in silence. On the rare occasions when they did complain, they would be regarded as eccentrics whose concerns could be trampled upon with impunity. It was always said that street lighting was needed to reduce crime and improve safety. Those that could, would observe from their back yards or from local parks where lighting was less obtrusive, or would go on holiday to dark locations. Dark skies in the U.K. were still available in the wilder parts of the U.K. right into the 1970s. By the end of the 1980s, light pollution globally was expanding at such a rate that dark skies in many areas This image of Milan taken by astronaut Samantha Cristoforetti from aboard the International Space Station was acquired after the transition to LED technology in the centre. The illumination levels appear to be similar or even brighter in the centre than the suburbs, and the amount of blue light is now much higher, which suggests a greater impact on the ability to see the stars, human health and the environment. Light pollution: The unrelenting bane of the amateur astronomer COURTESY OF NASA/ESA

31 of Europe, the Middle and Far East, and North America, were severely compromised. Professional astronomers would simply re-locate to remote locations, but amateur astronomers, being employed in regular jobs, did not have that option. They were condemned to live in and around cities, and would have to endure obtrusive street lighting outside their homes. Once street lighting has been installed, it was impossible to get rid of it. Astronomers now felt compelled to do something, and the Campaign for Dark Skies was established within the British Astronomical Association, and the International Dark Sky Association was launched in the United States. Pressure was brought to bear on local authorities and the lighting industry to manufacture dark-sky compliant lighting, and though this did have some mitigating effects, it took a long time to be adopted. However, such lighting can still be severely obtrusive if adjacent to a property where a back yard becomes floodlit. For anyone wanting to observe from the privacy of his/her home this is not acceptable. Furthermore, it is still impossible to get a street light removed if it is polluting one’s property. This has to change: a home-owner has a right to darkness within the confines of his own property. There are situations where street lighting is acceptable, but it has to be deployed in ways that it is not detrimental to the environment. Better designs are available in which the luminaire is fully recessed into its housing, so that it is not visible from a distance. All it does then is light the street, which is what it is supposed to do. Low colour temperature luminaires (not exceeding 1,750K) can be used that create a soft orange glow that does not hurt the eyes. In quiet residential and suburban areas street lighting can be subject to an 11p.m. till dawn curfew, so all lights are switched off when most people are not around. Furthermore, in these areas, with modern L.E.D. technology, it can be motion operated. This means the lights only come one when someone is in the neighbourhood of the light. In city centres, where a 24- hour society prevails, all night lighting can continue provided it is dark-sky compliant. Luminaires should only be sufficiently luminous to enable the eye to function efficiently in darkness. In these areas a luminosity not exceeding 700 lumens would be adequate, about as luminous as a 60W incandescent light bulb. In rural areas street lighting is totally inappropriate, and should be banned COURTESY Above, this image show the light pollution in Tabuk, Kingdom of Saudi Arabia. This is typical of many cities around the world. Below, low colour temperature amber L.E.D. light can be used to create a soft orange glow that does not hurt the eyes.

32 altogether. If these recommendations are adopted, the community will still have the lighting it needs, and there will be no loss of amenity. Furthermore they would also solve many of the light pollution problems affecting astronomers. Unfortunately motion operated lighting has never been adopted anywhere, even though some manufacturers have designed motion operated lighting systems. It’s a no brainer. So, lighting should only be deployed sparingly, on a must-need basis, where needed, when needed, in the correct amounts and using appropriate smart lighting technology. In addition to compromising astronomy, it is increasingly realized that light-at-night exposure is harmful to human health and the environment. It has been known for a long time that insects are attracted to lights, especially those with a substantial blue light component. Insects will fly around lights and may be killed outright by the heat from the light. Alternatively they can be so exhausted that they will drop to the ground, too tired either to feed or procreate. Street lights can be visible from a great distance by flying insects, so the lights of a city will sweep up insects like a vacuum cleaner over a wide area. With lights remaining switched on all night, 365 nights a year, the effect on insect populations is going to be devastating. Insect populations are going to decline. In the U.K. and elsewhere it was noted that in the mid-20th century, drivers traveling long distances in the summer would find their windscreens splattered with the dead bodies of flying insects that collided with the car. In recent years drivers can travel over similar distances and find their windscreens are as clean at the end of their journeys as they were when they started. Windscreen “splatometers” therefore can provide a useful measure of the health of insect populations in a given area. Some insects are so badly affected by lighting that it affects their breeding behaviour, and this has been observed in fireflies that require darkness so they can flash and attract mates. Lighting extends daylight into the hours of darkness, thereby inhibiting their flashing behaviour. In light polluted areas they will simply die off. So, lighting is going to cause insect populations to decline over wide areas, and this is going to have a concomitant effect on higher order consumers such as spiders, amphibians, reptiles, birds and small mammals. Environmental organizations have reported declines in these organisms over the past sixty years or so and these declines correlate negatively with the expansion of street lighting over the same period. Declines in insect populations are usually attributed to pesticides and habitat destruction. This is true, but light pollution was rarely ever considered as part of the equation until relatively recently, even though it was pointed out as early as 18972, and again in 19943. Bats are known to eat about 3,000 insects per night, so if insect populations decline, this could put severe pressure on the local bat population, resulting in bats not being able to find enough to eat. If lighting is killing of the insects, then the bats won’t get enough to eat, and they will be unable to build up the fat reserves necessary to keep them alive over the winter hibernation period. Insufficient food lowers their resistance to disease, and opportunistic infections may take advantage. Outbreaks of white nose syndrome, caused by a fungus, Pseudogymnoascus destructans4, have been observed in bat populations in the United States where starving bats have been seen foraging over the winter period. Declines in bats can have an effect on insects that are not attracted to lights; bats eat large numbers of mosquitoes, so if bat populations decline, mosquito populations may increase. It is now known that foraging behaviour in bats declines during bright moonlight, probably due to the increased risk of predation. If so, then it can also be expected to decline in areas that are permanently illuminated at night, leading to a concomitant decline in bat populations. The bats will simply move elsewhere. In the United Kingdom it is illegal to harm bats in any way, so this raises the question as to whether our municipalities are culpable by lighting up our environment to the point where they are denying food to bats and reducing their numbers. Light pollution could also affect the regeneration of tropical rain forests by disrupting the seed dispersal behaviour of fruit bats. In Costa Rica5 it was found that fruit bats avoided foraging The night sky is a precious natural resource that belongs to us all, and it should be afforded the same degree of protection as any endangered species. COURTESY Insects swarm around a flood lamp. It has been known for a long time that insects are attracted to lights, especially those with a substantial blue light component. Insects will fly around lights and may be killed outright by the heat from the light.

33 in illuminated areas, thereby having a negative impact on ecosystems. Under dark conditions fruit bats would produce a copious rain of seeds that would help rain forests recolonize land that had previously been cleared. Conservationists therefore recommend that dark refuges be connected by dark corridors to reduce the impact of light pollution by enabling bats to migrate from one sensitive area to another. Not only does lighting affect animals, but it also affects plants. Many flying insects are important as pollinators, and with insect populations declining, this is reducing the number of successful pollinations. This will have the effect of reducing plant numbers and diversity, and this will further backfire on insects dependant on plants for food, in a positive feedback cycle of ever spiralling decline. Many crops depend of insects for pollination, so this could ultimately affect crop yields. Consequently, farmers will not want street lighting in rural areas where they grow their crops. Light at night can also affect germination, flowering and abscission cycles in plants by interfering with phytochrome production, thereby preventing plants from adjusting to the seasons. Phytochromes are plant hormones that govern photoperiodism in plants enabling them to measure the hours of darkness and anticipate when to bloom, produce seeds, or drop their leaves in autumn. Disruption of phytochrome production will again have serious implications for crop production, such as strawberry plants failing to bloom. Deciduous trees exposed to artificial light tend to retain their leaves in winter. If normal photoperiodism is disrupted, then this will lead to further declines in plant diversity and concomitant effects on animals dependant on them for food. This could well include ourselves. Many animals are also dependant on trees for their natural habitat, so if trees are adversely affected they will have nowhere to live and consequently their numbers will decline. Photoperiodism in plants requires exposure to visible red light (625 to 760nm, and infrared (760nm to 850nm). Artificial lighting, particularly towards the red end of the spectrum such as sodium lighting, will therefore have an effect on photoperiodism in plants. This includes trees6. Lighting is now known to advance budburst in deciduous trees in the U.K. by 7.5 days7. Earlier budburst may further have an impact on those animal species dependent on the trees for food and habitation. Photosynthesis depends on shorter 15 wavelength light (blue – 400 – 450nm and red – 625 – 700nm). Green light has little or no effect on plants as this is largely reflected by the green pigment chlorophyll. Artificial light is not intense enough to affect photosynthesis, but orange lighting from street lights extends day-length, affects flowering patterns, and extends the period of growth into winter when the plant can be damaged by frosts and low temperatures. Furthermore continuous lighting is more damaging than part-time lighting. Human health is also affected by lighting. Until the advent of electric lighting humans tended to retire to their homes during the hours of darkness. Any lighting that was available was unobtrusive, such as candles and oil lamps that have a low blue light component. With the advent of electric lighting, daylight can be extended into the hours of darkness, and if the light is rich in blue light, it can suppress melatonin production by the pineal gland, located in the brain. Melatonin helps to regulate circadian rhythms in humans and other animals, and if this is disrupted, can have a disturbing effect on the individual affected. In addition, melatonin is oncostatic, meaning it suppresses cancers8. This occurs through interfering with the Warburg Effect9 that affects respiration in tumour cells. It has been reported that the incidence of breast and prostate cancer is more prevalent in areas that are lit up all night, as compared to those areas where it is dark. Reductions in bat populations may cause mosquito numbers to rise, possibly leading to the spread of mosquito-borne diseases such as malaria, filariasis, dengue fever, and Japanese encephalitis10. These diseases may then spread into areas COURTESY Road safety on motorways can be guaranteed by less intrusive methods such as reflective road studs (above) or cat’s eyes (inset).

34 where they never before existed, or where they had been eradicated. Recently it has been found that light pollution affects the biting behaviour of Aëdes ægypti, the Tiger Mosquito. Unlike most mosquitoes that bite at night, this mosquito tends to bite in the late afternoon and evening, and again around dawn and the early morning. Increased lighting at night extends the biting periods of the mosquito, thereby increasing the risk of infection by the diseases it carries, such as yellow fever, Zika and Chikungunya11. One of the main reasons for installing street lighting is the widespread belief that it reduces crime. This is now known to be a fallacy, but it is exploited by the lighting industry in order to sell more street lights, maximise profits, and safeguard their own jobs and those employed in municipal lighting departments. A study in Chicago12 demonstrated that increased lighting had no effect on crime rates. In the United Kingdom, where lighting curfews were reintroduced for economic reasons, it was found that criminality declined by as much as fifty percent. Some studies by the lighting industry suggested that criminality declined by as much as twenty percent, but these studies have long since been discredited. Where power failures have occurred, police forces were amazed to find that criminality declined almost to zero13, ergo criminals need light. Most of the crime we fear occurs in daylight, and lighting up communities extends daylight into the hours of darkness. This causes people to behave at night more as they would during the day, so criminality can be expected to increase. Many of the most crime infested areas in the U.K. are also the most intensively lit. Illuminating a property simply makes the criminal’s job easier, as he can see what is doing. If the place is dark, then he will be forced to bring his own lighting which is more likely to arouse suspicion. Motion operated lighting, if deployed correctly, can be a deterrent, as it will surprise any intruders and again arouse suspicion. It is also generally believed that lighting improves road safety. However, there are alternative methods of improving road safety without naïve recourse to street lighting. The blanket deployment of street lighting may lull drivers into a false sense of security, causing them to take less care, thereby increasing the risk of accidents. If the road is not illuminated, drivers will be forced to drive according to the conditions, and take more care. Motorways are often lit, with long stretches of illuminated roadway ramifying into open countryside where it is not appropriate. Road safety on motorways can be guaranteed by better, reflective signage, cat’s eyes, and raised crash barriers on the central reservation. Cat’s eyes are more efficient if the road is not illuminated. Raised crash barriers will render the glare of the oncoming traffic invisible, which is the main hazard on motorways when driving at night. Furthermore the advantages of these methods is that they don’t consume energy once installed, nor do they require much maintenance, if any. Unfortunately these recommendations are never applied, as they would deprive the lighting industry the opportunity to profit from the sale of street lighting. Street lighting, if deployed Vanity lighting includes illuminated public buildings such as this one (left) in Istanbul, Turkey, and skybeams like the Stockport Skybeam, Stockport, Cheshire, pictured below in this 2005 image. COURTESY

35 1) Rundetaarn.dk https://web.archive.org/ web/20090227083344/http://rundetaarn.dk/engelsk/ frames.htm 2) Electricity and English Song Birds. Los Angeles Times, September 14th., 1897. 3) Henshaw, C. The Environmental Effect of Light Pollution. JBAA, Vol 104, No 6, 313. November 1994. (Journal of the British Astronomical Association). http://articles.adsabs.harvard.edu//full/seri/ JBAA./0104//0000313.000.html 4) U.S. Fish and Wildlife Service. (2008) The White Nose Syndrome Mystery: Something is killing Our Bats. http://www.fws.gov/northeast/white_nose.html 5) Levanzik, D., and Voigt, C., (2014), Artificial light puts Ecosystem Services of Frugivorous Bats at risk. https://besjournals.onlinelibrary.wiley.com/doi/ pdf/10.1111/1365-2664.12206 6) Does Night Lighting Harm Trees? http://physics.fau. edu/observatory/lightpol-Plants.html#LAN_on_Trees 7) Ffrench-Constant, R.H., Somers-Yeates, R. Bennie, J., Economou, T., Hodgson, D., Spalding, A., and McGregor, P. K. Light pollution is associated with earlier tree budburst across the United Kingdom. Proceedings of the Royal Society B. Published 29 June 2016.DOI: 10.1098/rspb.2016.0813 http://rspb.royalsocietypublishing.org/ content/283/1833/20160813 8) Kloog, I., Haim, A., and Portnov, B. A., Investigating the Links between Nighttime Light Pollution and Breast Cancer: a Geographic Information System (GIS)-assisted study. Accepted for publication: see abstract, Chronobiology International, (2005) 26 (6) 1240. 9) Devic, Slobodan, Warburg Effect – a consequence or the Cause of Carcinogenesis? Cancer 2016; 7(7):817-822. doi:10.7150/jca.14274 10) Henshaw, C. The Ecological Implications of Light at Night. 2017. https://www.academia.edu/31172472/ The_Ecological_Implications_of_Light_at_Night_LAN_ 11) Lin, Sarah Belle Another reason to turn off Lights, December 3rd., 2018. http://www.oaklandmagazine.com/December-2018/ Another-Reason-to-Turn-Off-the-Lights/?fbclid=IwA R1feeRCyD8ZpY7Dwo5obbbAPqQL6MYvp8EvcAl3-8- WrB0vz9PdsBPYEr8 12) Hutton S. and Morrow, E., The Chicago Alley Lighting Project, Illinois Criminal Justice Information Authority, 2000. http://www.icjia.state.il.us/ public/pdf/ResearchReports/Chicago%20Alley%20 Lighting%20Project.pdf 13) Mitchell, John, quoted by Lilley, Ray. The Columbian, 03-08-1998. Criminals take a break in blacked-out Auckland. http://www.highbeam.com/ doc/1P1-5702801.html References • Transports in a Compact Car • Easy One-Person Collimation • Smooth Movements with Clutch • 2-inch Two-Speed Rack & Pinion Focuser 16-inch F/4.5 Truss Tube Dobsonian Deep Sky Euphoria! www.explorescientific.com responsibly can be construed as useful. However, there is another aspect of light pollution that cannot be construed as useful by any stretch of the imagination. This is vanity lighting, that does not serve any useful purpose apart from providing eye-candy to an ill-informed proletariat. Taxpayers will not want to see their local taxes squandered by ignorant corporate executives and local government bigwigs on an ego trip. This kind of lighting includes illuminated public buildings and monuments, skybeams, lasers, urban regeneration follies and illuminated “art” projects. Urban regeneration follies are illuminated projects that some factions in local government believe can regenerate depressed areas and bring money into the community. They are harmful to the environment and in violation of the municipality’s mission statement to protect it. Vanity lighting is simply wasteful of energy at a time when energy consumption should be cut back due to concerns about climate change, while at the same time adding to existing light pollution already caused by street lighting. Consequently vanity lighting should be banned, or at least substantially cut back. Light pollution, then is a serious problem, not only to astronomers, but also for the environment in general. However there is no attempt here to eliminate street lighting but a universal culture change is needed in our attitudes towards outdoor lighting. If deployed responsibly it can be beneficial, with minimum impact in the environment, human health, and the night sky. The night sky is a precious natural resource that belongs to us all, and it should be afforded the same degree of protection as any endangered species. The recommendations made here show how this can be done, while at the same time providing the lighting that communities need.

36 By DANG TUAN DUY Guest Contributor Vietnam is a developing country and on its way of economic development. However, astronomy is still not being much noticed in Vietnam, even its significant impact on the awareness and imagination of human. Therefore, our club, since the date of establishment, always focuses on the two main objectives. First, we aim to build up a coherent, unique online website to coordinate activities of astronomy enthusiasts in Vietnam and to spread out astronomical news and knowledge in a more organized way. Secondly, we organize various observing nights and hands-on activities in Ho Chi Minh city, the south of Vietnam, and remote provinces to increase awareness of people about astronomy. In response to our goals, Ho Chi Minh City Amateur Astronomy Club (HAAC) continues to pass this information along through our basic astronomy programs developed for children, students and astronomy enthusiasts. Our organizations offers special workshops and seminars covering fundamental subjects like observing the sky, Solar System, Black Holes, Kepler’s Laws, Stellar Evolution and many others. The club also partners with teachers at the local high schools by conducting practical astronomy and astrophysics sessions. We also found that there will be more impacts if there are some professional astronomers/lecturers who could join us and talk to the audience about their own experiences. We wouldn’t be where we are today without their help. So, for enhancing activities of Vietnamese amateur astronomy clubs, the most important target is communicating with local teachers, parents, and especially local students and children. During these activities, the club adds that right now the priority is to learn more about sky phenomena like eclipses, conjunctions, meteor showers and transits so we can be ready for the events. All the events are planned to consist of: workshops on astronomy themed science talks; astronomy for public outreach; astronomical knowledge dissemination for students and children; international networking and cooperating in astronomy; and sky parties, for sure. For local connections, the club run lots of monthly meetings, astronomical camps, observations and specific projects such as: Eratosthenes project for measuring Earth’s circumference for students and teachers, “Annual Volunteer Young Intellectuals” held by Ho Chi Minh city Youth Union, Ho Chi Minh City Water Rocket Challenge, series of talks and contests (egg-drop) at high schools/ Culture House of Youth/Children House, astronomical popularization at SOS village or orphanages, etc. For international projects, HAAC continuously showed great efforts to join a global network based on common interest by connecting with astronomy enthusiasts all around the world. For Astronomers Without Borders, Ho Chi Minh City Astronomy Club was one of the first affiliates to join back in 2008.” The club had participated in IYA 2009 activities such as 100 Hours of Astronomy and Galileo Nights, Globe at Nights, Space Scoop, annual GAM events, partnering with other groups for the “30 Days of Star Peace” program, and acting as National Coordinator for World Space Week and Universe Awareness program. The club also acted as an alternative contact, IAU (International Astronomical Union) - Office of Astronomy for Development project in Vietnam (2013 Phase 1 “Bringing Astronomy to Remote Areas in Vietnam” and 2014 Phase 2 “Coordinating Astronomy for Public Outreach in Viet Nam (Phase 2): Uniting Amateur Club is on a mission to expand access to astronomy in Vietnam Narrowing the gap COURTESY OF HAAC Ho Chi Minh City Amateur Astronomy Club members conduct public observation sessions with a telescope donated by “Telescopes for All”.

Astronomy Clubs and Bringing Astronomy to a Broader Public”). Saigon Astrokids (SAK), a social project run by Ho Chi Minh Astronomical Association and Ho Chi Minh City Amateur Astronomy Club (HAAC), aims to utilize astronomy and its starry stories to inspire Vietnamese children, specifically orphaned youths. Our vision is to build up young generations with love, skills, and career passion for astronomy. We have seen the increasing need for astronomy outreach and education for children and pupils. Together with other managing members of HAAC, I founded SAK with the hope that it could ease this high demand from families and schools, and create a playground as well as a carefully planned training course for kids under 13 years old to discover themselves. Therefore, from 2017 to now, lots of courses, wellprepared observations and astro-camps with telescopes had been designed to connect our kids with meteor showers, eclipses, moon and stars. Given the context of Vietnam and its low-level status of astronomy development, SAK has become more motivated to carry out the best plans and activities possible, to look for as much resources and equipment as possible, and looking outward to practitioners and researchers worldwide is one way to narrow the gap between our homeland and the rest of the world. n n n Dang Tuan Duy (Mr.) Ho Chi Minh City Physical Society - Ho Chi Minh City Astronomical Association Chairman- Ho Chi Minh City Amateur Astronomy Club (HAAC). National Coordinator- Astronomers Without Borders (AWB) COURTESY OF HAAC Above, an experiment to determine Earth’s circumference is demonstrated at a club event. Below, a child participates in a club event. 37

38 By PIERRE PAQUETTE Guest Contributor My cabin had been in disrepair for a few years, so I eventually started making a few repairs by myself. Bad idea, but it did keep me busy for many weekends, so when I finally resolved to sell it instead of trying to fix it, I ended up with idle hands. I needed something to keep my hands occupied. On something smaller, preferably. This is how I decided, in January 2015, to build a planispheric brass astrolabe. The astrolabe used to be a pivotal instrument on the desk of all astronomers from its invention around 2,000 years ago until around 1600… but before I tell you why such was the case, I need to tell you what an astrolabe is and what it’s used for. Most people interested in astronomy have heard of Greek astronomers such as Hipparchus and Ptolemy. Few, though, have heard about the instruments our forebears were using. One of them, the armillary sphere, consists of a set of rings around a central ball or sphere representing the Earth. It was invented independently in China and in Greece around the third to the first centuries before the Common Era (BCE). Three parallel rings represent the equator and the tropics (those two being smaller than the equator), with a fourth representing the ecliptic, inclined and touching the top (or Cancer) tropic on one side and the bottom (or Capricorn) tropic on the other side. A fifth ring is perpendicular to the equator and tropics and represents the meridian. It’s a beautiful instrument in and by itself, and I was always amazed when I would see the Meritas Trophy, an armillary sphere made by Québec (Canada) amateur astronomer Réal Manseau in the 1970s, which won a few prizes at Stellafane convention in Vermont (USA) and is offered yearly by the Québec Amateur Astronomers Federation to one of its members who participated in outreach programs and such. Legend says that Greek astronomer Ptolemy was riding his camel or horse one day, and that his armillary sphere fell off and was trampled upon by the animal. Upon picking it up, he supposedly realized it could still be used, and that he came up with the astrolabe from what remained. While this story is most likely not true, the planispheric astrolabe Brasstronomy Astrolabe project brings ancient astronomy into the present day COURTESY OR PIERRE PAQUETTE The author’s completed brass astrolabe

39 appeared around that time in the Greco-Roman world (we speak of Ptolemy as “Greek,” but that’s only his origin, as he lived in Egypt which was then a part of the Roman Empire). The name of the instrument comes from Greek ἄστρον (ástron, “star”) and λαμβάνω (lambánō, “I take”), meaning “I take stars,” as it is an early form of planispheric star map. The instrument gradually evolved into its “modern” form thanks to the Arabs and Muslims, who came upon it first through commercial exchanges with the Roman Empire, but later through their conquest of not only Egypt, but all of North Africa and even a good part of modern Spain after crossing the Gibraltar Strait. While the Western Roman Empire collapsed in 476, it had been split in two almost 200 years prior to that, and the Eastern Roman Empire lived on until 1453; it was a major gateway for GrecoRoman science into the Islamic world. But back to the instrument. It is composed of a main plate, or mater (Latin for “mother”; also called umm in Arabic, of same meaning), which is usually recessed and surrounded by the limb. In the recess are housed interchangeable plates called tympans or climates, which are engraved with a set of lines corresponding to a given latitude—more on that soon. Most astrolabes are fitted with four tympans, covering eight latitudes on their front and back sides, or seven sides for the climates plus one side inscribed with other bits of information. On the front of European astrolabes, but rarely of Islamic ones, we find a movable ruler, which may or may not be inscribed with graduations, that can pivot around a central pin. The back of the astrolabe is inscribed with an ecliptic circle as well as a calendar circle, and most often also contains a shadow square and sometimes other information. On that side, the central pin holds a movable alidade (from Arabic terms meaning “arm”) bearing pinnules, vanes through which one may aim at the Sun or a star. (WARNING: Never look at the Sun directly, either through an astrolabe or a telescope! It may permanently damage your eyes and turn you blind. To point the Sun with an astrolabe, use the alidade instead to project a shadow and align it with the bottom pinnule.) The set of lines engraved on the tympans are the almucantar (from Arabic terms for “arch”), which are parallel to the horizon and are thus altitude lines, and the azimuth lines which cross each other at the local zenith, the point above the observer’s head. The final piece of the instrument, placed on the front of the instrument, between the ruler and the tympans, is the rete (Latin for “network”; Arabic ‘ankabūt, “spider”, hence the common French word “araignée” of same meaning).

40 This is a combination of three concentric circles—the outer tropic of Capricorn, the median equator, and the interior tropic of Cancer—and an off-centered circle for the ecliptic, whose top touches the tropic of Capricorn and bottom touches the tropic of Cancer. Where the astrolabe becomes a piece of art and craftsmanship is that the rete also bears a number of star pointers—finding a way to combine all that into a single piece of sculpted metal allows the astrolabist (maker) to express their artistic and ingenuity talents. When I started the project, I knew nothing about astrolabes. I obviously turned to Manseau, whom I knew had made some astrolabes… but he surprised me when he said he never made any planispheric astrolabes, only mariner’s astrolabes. (The mariner’s astrolabe is basically only a 360° protractor with an alidade and its pointing vanes; mind you, Manseau’s instruments are beautiful nonetheless!) Luckily for me, I then had a very supportive girlfriend: she offered me The Astrolabe, an excellent book by James E. Morrison (I was very saddened, in 2016, to learn of Morrison’s passing; the book is now out of print and becoming ever more difficult to find and increasingly more expensive—and no, my copy is not for sale). While it doesn’t mention anything about metalworking, it covers both the theory and practice of the astrolabe and many of its variations. One such variation is Gunther’s quadrant, which is basically a “folded” astrolabe without the star map. I decided that would be a nice first instrument to practice with, so I acquired a sheet of steel from the local hardware store as well as a Dremel hand engraver and started working on it right away. For a first try, I was reasonably happy, except that the engraving machine vibrates too much, even at its lowest setting, and my lines and curves were very jiggly. (A few years later, I obtained an earlier version of the same machine, with an even lower setting, and was able to make nice lines with it.) Time to move on to the astrolabe. Back to the hardware store. What? No brass plates? I thought I’d find that easily! I eventually found a metal distributor who, importantly, mentions on their website they have “no minimum order,” and got two 2 mm brass plates from them—one for a mater-tympan combination (I didn’t need seven climates, so just one side of a tympan was enough; might as well incorporate it in the mater at that point), and the other for the rete. An important point in the design of an astrolabe is that the thickness of each line will affect the precision of the instrument. When the line is too thick, it is more difficult to

41 know if we’re using its precise center or if we’re a little off. Another consideration I had was the environment—etching copper-based alloys is done with ferric chloride, a highly corrosive and acidic product which cannot be disposed of in water-sewage system. We also had kids and an animal at home, so I didn’t want to risk poisoning them—I had to find a way to do without the etching solution! (I had manipulated the product about two decades prior, so I had some familiarity with it, but still…) Finally, and after a few tests, I decided that I would engrave my brass plates with a scriber—a tool normally used to scratch off paint or a similar coating product from metal plates in order to draw guiding lines. By scratching the exact same spots five times over, I was getting lines that were easily seen and usable, but still thin enough to allow for high precision when making measurements. The rim of the front plate serves as the limb. It is inscribed with 360 degree marks on the inner graduation, plus 288 lines to mark time—one every five minutes. The rete also bears 360 degree marks on its rim, plus 360 other marks on its ecliptic. The calendar and ecliptic in the back bear 365 daily and 360 degree marks. Finally, my front ruler has 85 degree marks and the back alidade plus 37 minute marks to read a curve for the equation of time, a modern addition to the astrolabe back which I chose instead of drawing a shadow square that I would most likely never need. That’s a total of 2,215 straight marks (11,075 scriber strokes), not counting the circles (full or partial) and the kidneyshaped curve for the equation of time. Speaking of the circles, the smallest (for the 85° almucantar) has a radius of approximately 3.5 mm, but the largest—not counting the north-south line, which is technically a circle of infinite radius—has a radius of approximately 1.5 meter. Needless to say, my regular metal divider caliper (aka compass) doesn’t reach that far; I had to use some stock metal bars from the hardware store, through which I ran a nail as a pivot at one end and affixed my scriber at the other end, laying everything down on the floor of the dining room and part of the living room floor! Once engraving was finally done—a few hours over several days or weeks; I didn’t count my time—I could proceed to the cutting of metal pieces. I obtained an electric scrolling saw, but it proved too noisy for my taste. Plus, I was living in a second-story apartment, with no outside shed in which I could work, and a metal shard found its way underneath my girlfriend’s daughter’s eyelid. It was easy enough for the doctor to remove it without surgery, though the poor kid was scared enough of the tweezers in her eye that she had to be sedated, but my girlfriend rightfully forbade me to work in the apartment anymore. And since I live near Montréal, where it can get too cold to work outside for maybe half the year, not counting the many rainy summer days, I basically stopped working on the astrolabe. A few years later, my girlfriend and I broke up and I went on to live by myself. While I’m still in a secondstory apartment, I did take one with an extra room that became my workshop. I eventually finished cutting out my astrolabe, but doing it by hand was very slow, so what I did was use a circular blade on a rotary power tool for the rough cut, then use a jeweller’s file to finish the cut to the precise line or curve I wanted. Needless to say, that involved a lot of elbow grease! The Montréal area is often used by moviemakers for filming, and eventually, word came to me that one such production was in search of astronomy-related items. I t has been reported that, in the tenth century, ʿAbd al-Rahmân al-Sûfî wrote a book which mentioned 1,000 uses for the astrolabe. While this book is now lost to History, we still know today multiple uses for this ancient instrument. The following list is very incomplete: • Telling the time from the Sun • Telling the time from stars • Knowing the time of sunrise or sunset for a given date • Knowing the time of the start and finish of twilight (civic, nautical, or astronomical) for a given date • Knowing the right ascension and declination of a star • Knowing our own latitude (obviously known by the astrolabist, but not necessarily by the user, which is not always the same person) • Knowing the maximum altitude the Sun will reach in the sky for a given date • Knowing the rising times of zodiac signs, an information that was very useful to ancient astronomers • Knowing the time of rising and setting of any of the stars on the rete • Knowing the ecliptic longitude of the Sun for a given date • Knowing the dates when seasons begin and end Altogether, it’s an instrument that allowed one to get a wealth of information rapidly and easily—hundreds if not thousands of years before any modern astronomy software was invented! What can you do with an astrolabe?

42 I offered them my astrolabe, and they took it: It is supposed to be in a windowed exhibit during scenes supposedly taking place inside Griffith Park Observatory. Funnily enough, another part of the movie was filmed in and around the building just behind my work office: That tower will appear as an FBI building. Now that it’s back home, my astrolabe found its spot on a recess in my window, next to a plastic sextant an acquaintance gave me after he got disinterested in astronomy (wait—how is that even possible?) and a few plants. Do I ever use it? Sometimes—but it was drawn for my old apartment, and would give erroneous results here, as I’m about one-fifth of a degree of latitude further south. Nevertheless, even though it was then unfinished, it was still complete enough to be used at my previous address, where I repeatedly got results precise to the minute. At the new address, I’m still within two minutes. Speaking of using it, how does one use an astrolabe? First, the position of the Sun along the ecliptic is found by aligning the back alidade with the date on the calendar curve—a circle slightly offset from the center of the ecliptic circle. The degree of ecliptic longitude is then found on the ecliptic curve where the alidade crosses it. For example, for July 1st, one reads Cancer 9°. One then measures the altitude or height of the Sun in the sky. This is one by hanging the astrolabe from a ring placed at its top (through a part called the throne, which is minimal on mine but is sometimes lavishly decorated on other instruments) and letting the Sun shine through one vane of the alidade onto the other vane—the altitude is found when the point of light falls in the lower vane’s hole. The next operation is to turn the astrolabe on its back—it is normally used on a table from this point on, with north up—and to align the point of the rete’s ecliptic curve corresponding to the Sun’s longitude (Cancer 9°) with the almucantar of the measured altitude. I drew almucantars for every 5°, so if the measured altitude is not a multiple of 5, let’s say 37°, I judge by eye where the 37° curve would be and place the ecliptic point there. Now, of course, any point of the ecliptic can be set to cross the almucantar in two different points: one in the morning and one in the afternoon. Care must be taken to select the proper one (East of the meridian line in the morning, West in the afternoon). If one doesn’t know whether it’s morning or afternoon, another measurement taken 15–20 minutes later will show the Sun higher in the sky if it’s morning, or lower if it’s afternoon—except of course around Noon, but that’s a different story… Finally, the ruler is aligned with the ecliptic point of the Sun, and its edge on the limb will show the time of day. For example, 37° of Sun altitude on July 1st means it’s 7:00 or 16:00 of local true solar time. Most locations are not exactly on their time zone’s central meridian, so a correction in longitude must be applied (yet another difference between my old address and the current one). Also, many states and countries have a different time for part of the year, usually called “daylight saving time”— from the second Sunday in March to the first Sunday in November for the United States and Canada— implying another possible correction. Finally, there’s the equation of time I mentioned previously, which has two causes: Earth’s orbit is an ellipse and not a circle, and the Earth’s rotation axis is tilted, resulting in the Sun not following a straight path in the sky (higher in the summer, lower in the winter). The result is that days don’t always exactly 24 hours but may be a few seconds shorter or longer. This difference accumulates and can reach about ±18 minutes. This is the reason why I engraved a curve for it in the back of my astrolabe. It’s night and the Sun is gone? No problem! Simply measure the height of a star that’s represented in the rete and place its pointer at the altitude you measured. Then, align the ruler with the Sun’s ecliptic position, and you’ll find the time on the limb. My astrolabe has pointers for 21 stars, and seven more can be inferred from shapes, as Orion’s belt is on the equator stripe and I sculpted a miniature Big Dipper straddling another metal stripe. Astrolabes nowadays are most often found in museums. I saw a few at the Arts and Crafts Museum in Paris and a few more at the Aga Khan Museum of Islamic History in Toronto (Canada). I had the pleasure of being invited to the latter to give a five-hour workshop on the instrument, during which I showed attendees how to draw their own astrolabe and how to use it. We then went to see the museum’s astrolabes, on which I commented about their similarities, differences, decoration, etc. Each attendee left with an astrolabe made of cardboard and clear plastic as well as a 36-page booklet, that I got printed for them at a local print shop. Recently, I also sent the same cardboard/plastic astrolabe and booklet to an astrophysicist who read about my astrolabe on Twitter, but customized to her own location in New York State rather than in Toronto (Canada). I believe the astrolabe can serve as a great educational tool, and on many respects: Through it, one can not only learn about astronomy and the path of the Sun and stars in the sky, but also about the history of astronomy, a subject which had always captivated me, but since early 2015 when I started working on my own astrolabe, has been a top interest of mine. Should you want your own astrolabe, whether it’s made of cardboard and clear plastic or of brass or another metal, I’ll be happy to advise you and see what I can make for you, tailored to your needs and to your budget. You may reach me at [email protected]. Clear skies!

43

44 By MYRON WASIUTA and LINDA BILLARD Guest Contributors This is the story of the fulfillment of a dedicated amateur astronomer’s dream in ways even he probably could not have imagined. It began sadly in March 2015, after Mark Slade, an avid local central Virginia astrophotographer, had passed away unexpectedly. I had known Mark for almost 25 years and had spent many nights under the stars with him. We became steadfast friends. He wasn’t just an amateur astronomer—he was an expert astrophotographer. Mark’s passion was taking pictures through his telescope. He built an entire telescopemounting and optical tube assembly dedicated to astrophotography. Back in the early days of our friendship,- we didn’t have CCDs or computers—just film and darkrooms. (Fig. 1.) Mark loved sharing his enthusiasm for astronomy and his photographs with anyone and everyone. He would set up his telescope on the sidewalk in front of libraries and at Fig. 1 (above): Mark Slade with his homebuilt telescope system 1995 Fig. 2 (right): the MSRO Station One enclosure with 6-ft Technical Innovations dome One-of-a-kind facility for observing the universe Mark Slade Remote Observatory:

45 the local mall, inviting folks to have a look at the Moon or the rings of Saturn. After a few minutes, he would bring out his photographs and begin explaining the secrets they contained. “This galaxy has a hundred billion stars,” he would say, or “right here in this blurry spot is a Black Hole!” He especially loved engaging young people— hoping to instill an interest or awaken a curiosity in their minds. Mark had always wanted an observatory for his telescope, a place where it could be set up permanently in his backyard and be protected from the weather. He had acquired almost everything needed to complete an observatory dedicated to astrophotography. Sadly, in January 2015, he unexpectedly died before his observatory was completed. Soon afterward, I received a call from Laura Slade, Mark’s widow, offering me all of Mark’s telescopes and equipment. It was at that moment that I had an idea—I would use Laura’s generous gift to build an observatory and dedicate it to furthering Mark’s legacy by making it available to the public, including instruction and telescope time at no charge! I envisioned this observatory as being available remotely to anyone interested in exploring the wonders of the universe through astrophotography, outreach, and research. Getting from an idea to an actual working observatory that met these requirements was a huge undertaking— much more than I could achieve alone. I needed the help of someone who knew how to implement all the electrical, computer, and software subsystems that would be needed. That person was Jerry Hubbell, who, along with Richard J. Williams and Linda M. Billard, had written an entire book about remote observing titled Remote Observatories for Amateur Astronomers-Using High-Powered Telescopes from Home. As luck would have it, both Jerry and Linda were in my local astronomy club, the Rappahannock Astronomy Club (RAC). I remember that first meeting with Jerry. I was somewhat apprehensive because he was a busy published author, but I felt he was absolutely essential to have on the team. However, because we were only casual acquaintances, I really didn’t know whether he would be interested in taking on a project of this size. Well, within 5 minutes of pitching my idea to Jerry, not only was he on board, but was already thinking about how we could make this project bigger and better! I knew I had found the right person to help get this observatory online and operational. And so, it was that in spring 2016, Jerry and I co-founded the Mark Slade Remote Observatory. In addition to the obvious hurdles of getting the telescope, cameras, dome, and software to Fig. 3 (above): The Explore Scientific 6.5- inch 165mm ED APO installed in MSRO Station One Fig. 4 (left): The Meade 12-inch LX200 Station Two telescope

46 work, we realized the concept of an educational facility dedicated to outreach and research also needed a talented team of people from different areas of expertise, such as public relations, fundraising, website design, machining, and of course, astronomy. In addition, we saw that there needed to be some form of administrative oversight and that this group of experts could serve that function as well. In November 2015, as work progressed on the observatory itself, the Mark Slade Remote Observatory (MSRO) Commission was formed. In addition to Jerry and me, members included Dr. Bart Billard (physicist, instrument design), Linda M. Billard (author, editor, website design, illustrator), and Ron Henke (then RAC President). Soon, Lauren Lennon (staff astronomer, NASA solar system ambassador), Shannon Morgan (NASA solar system ambassador, outreach coordinator, website design, software specialist), and Matt Scott (machining and mechanical engineering and design) were added. Over the winter of 2015 and into the spring and summer of 2016, the MSRO Commission met every month and completed the observatory with generous donations of time and funds from its members, as well as contributions from RAC and several private individuals. (Fig. 2) The first telescope was a Meade 12-inch SCT under a 6-foot dome, with filter wheel and CCD camera. The observatory was constructed behind my home, which is located under fairly dark skies. Almost immediately, it began to be used by local high school students for senior Culminating and Capstone Projects. In addition, amateur astronomers from places as diverse as Canada and Bangladesh began to make photometric and spectroscopic observations of variable stars. In addition, MSRO Commission members used the telescope for observation. As observations and use continued, it became apparent there were limitations, and eventually, the telescope control system failed. In response, the person and company that would become our most important benefactor—Scott Roberts and Explore Scientific (ES)— entered the story. Jerry Hubbell, who is currently the Vice President of Engineering at ES, talked with Scott, and eventually procured, on long-term loan to Jerry, a Losmandy PMC-Eight mount and telescope control system. Jerry (along with ES) then provided ES’s flagship refractor, the 165mm f/7 apochromat. This became the main telescope at MSRO, which is still used today. (Fig. 3) Although private funding was used (and still is) to initially operate the observatory and allow users to observe without cost, the members of the MSRO Commission recognized that fundraising would be important if MSRO was to be viable into the future and continue to provide free telescope time to observers. In addition, the Commission envisioned bringing other telescopes online relatively easily using the model and experience gained with the 165 APO. Additional weathertight enclosures could be built to house these additional telescopes, and they could be easily incorporated into the existing framework of computers and networks. In other words, if MSRO was to grow, money would be needed at levels greater than the handful of donors could provide. The Commission decided to form a non-profit 501-c3 tax exempt organization and disband itself in favor of a Board of Directors. This was accomplished in fall 2019 with the formation of MSRO Science, Inc. The little observatory in Virginia could now offer tax advantages to those wishing to make monetary and/or equipment donations to help with the organization’s vision. Incorporation as a non-profit helped us to receive substantial help—of course from Scott Roberts and ES—but in addition, from others who made donations, including Bruce Morell of Astrofactors, who helped with some of our CMOS cameras, and Tom Field of Field Tested Systems who donated a spectrographic grating and RSpec spectroscopy software. In addition, David and Debra Giesen of Photonics Cleaning Technologies, LLC, donated a deluxe First Contact Cleaning kit to help keep the lenses and mirrors in our telescopes professionally clean. Since MSRO Science was formed, the organization has also Fig. 5: The MSRO Station Two enclosure.

received generous donations of filters, telescopes, and a high-end telescope mount. (Fig. 4) So, what does the observatory look like now—5 years after Jerry and I had that initial meeting? Currently, MSRO Science has three independent telescope stations, each available online for use remotely. Station 1 is the original domed enclosure with the ES 165mm APO paired with a filter wheel and QHY 163C camera. The Losmandy G11 PMC-Eight mount uses an ES Telescope Drive Master (TDM), which allows <0.5 arc-second RMS tracking, thus eliminating the need for autoguiding. Station 2 has a 12- inch Meade LX-200 SCT on a Celestron CGE Pro Mount also with a TDM. It has a filter wheel with a full complement of UVBRI filters and a spectroscopy filter. (Fig. 5) Station 3 has an ES 102mm f/7 APO with QHY 178C camera for color astrophotography. (Fig. 6) Soon, it will also have a TDM and will be upgraded to an 8-inch Ritchey-Chrétien telescope. All stations are accessible online by using desktop sharing programs. The guest users need only install TightVNC Viewer (free and open-source) on their computers, and once they have received the connection passwords, theycan connect to the telescopes. (Fig. 7) What makes MSRO different, other than providing users with free access to high-quality telescopes? I would sum it up this way. Other online telescopes don’t allow the person requesting observations to actually control the telescope. At MSRO, we will provide access to training videos and then actual personalized training to allow the user to feel comfortable operating our remote observing stations. All aspects of operations are covered in training, from connecting and operating the software, to slewing to the target, obtaining optimal focus, plate solving (if necessary), and then taking the images. We will even help with analyzing the data if desired. We also provide entrylevel astrophotography tips and training—all in the spirit of Mark Slade and his passion for capturing the beauty of the night sky. 47 Fig. 6 (left): The Explore Scientific 4-inch 102mm ED APO in the MSRO Station Three enclosure. Fig. 7 (below): A view of all three stations at the Mark Slade Remote Observatory (MSRO)

I hope this observatory helps carry on Mark’s legacy of public education and promoting an interest in science and photography. Who knows, perhaps a young user of this observatory will be inspired to go on someday and make amazing discoveries in science or other fields. If you would like to know more, or have an interest in using the observatory, visit www.msroscience.org, or email me directly at [email protected]. There is also a Facebook page dedicated to the Mark Slade Remote Observatory. n n n Dr. Myron Wasiuta is the Chairman of the Board and President of MSRO Science, Inc., and Founder of the Mark Slade Remote Observatory (MSRO). A life-long amateur astronomer, Myron is an Optometrist by trade. He is the past president of three astronomy clubs, the Rappahannock Astronomy Club, Northern Virginia Astronomy Club, and the Birmingham Astronomical Society. He has taught astronomy at the University of Mary Washington, and has had observing rights at the US Naval Observatory in Washington, D.C. His astronomical interests include imaging faint, obscure galaxies, and cataclysmic variable stars. Linda Billard is a Member of the MSRO Science, Inc. Board of Directors. and serves as a technical writer and editor for MSRO Science, Inc. She owns and operates her own small business Billard Communications. + Precision Optics + Bulit to Explore + Created by Astronomers to Learn the Night Sky FIRSTLIGHT TELESCOPES EXPLORE ALLIANCE EXPLORE Questions/Comments? 866.252.3811 ©2020 Explore Scientific, LLC. All rights reserved. Learn more at explorescientific.com 8x42 10x42 NON-ABBE PRISM TETON ABBE PRISM Simulated Images WATCH EXPLORE ALLIANCE LIVE Learn from the Explore Alliance Community and Special Guests. explorescientific.com/live LIVE daily at

49 By DIMITRIE OLENICI Guest Contributor The Rosette of spiral diagrams of Saros series of solar eclipse was elaborated by the author in the 1990s as a prelude to the total solar eclipse of August 11, 1999, which had the center in Romania near the town of Ramnicu Valcea. With this occasion the author has published a book (in Romanian) about eclipses entitled The eclipse since the Sun the Moon and the World exists (Eclipsele de cand lumea, Soarele si Luna, Editura Casei Corpului Didactic, Suceava, 1999 – in Romanian). The book was reedited in 2015 when the spiral diagrams of Saros series of solar eclipse was added to the text (Olenici, 1999). In 2007, a poster entitled The spiral diagrams of Saros series of solar eclipse was presented at the Solar Eclipse Conference SEC2007, held at Griffith Observatory in Los Angeles, USA. The results were well received and a total of 75 posters were distributed to participants. A similar poster was presented by us for the lunar eclipses at the Solar Eclipse Conference (SEC 2011) held in New Delhi India. In this article a novel representation of the Saros series as a rosette of spirals is proposed. It creates an overview of the eclipses occurring over a long time span, helping in better understanding the notions of Saros cycle and Saros series. At the same time, we notice the use of spirals throughout history as a solar symbol. ABOUT SAROS CYCLES AND SERIES It is well known that the Chaldeans, a tribe near the ancient city of Ur, discovered that, the eclipses were repeated almost in identical conditions after an interval of 18 years and 11 days. The cycle discovered by the Chaldeans was named Saros by Halley in 1691 (Neugebauer, 1975). It may derive from the word šäru (meaning 3,600), a term wrongly identified with a period of 18 1/2 years. Instead, the word sara, a period of 6585 1/3 days (223 lunations), well-known by Babylonians, may be better suited as original term (Yeates (1820) and Picke (1837) on page 471). The cycle was improved by the Greek astronomer Meton in the 5th century BCE. It is widely known that Babylonian astronomy influenced Greek astronomy and that by Alexander the Great’s conquest of Babylon in the 4th century BCE more than 1,903 years of astronomical observation made by Babylonians were transmitted to the Greeks, some at the request of Aristotle. Ptolemy cites for instance ten Babylonian observations of lunar eclipses ranging between 721–382 BCE. The Chaldean astronomers attributed to the possible discovery and later improvement of this cycle are Kidinnu (Cidenas) in the 4th century BCE and Naburiannu (Naburianos) at the end of the 6th century BCE (Fotheringham, 1928) both influencing the work of Hipparchus in the 2nd century BCE. The cycle discovered by the Chaldeans attracted the attention of modern astronomers to discover the causes that produce this periodicity. It is known that when a solar eclipse occurs, the Moon is in the lunar phase New Moon or conjunction, and a lunar eclipse occurs when the Moon is in the Full Moon phase. that is, at the opposition. The time interval after which the Moon returns to the same phase is called the synodic month and has the duration S = 29.5305881 days. If eclipses depended only on the synodic period, then in each synodic month there would be a lunar eclipse and a solar eclipse. Through observations it was found that not every time the Moon is at the conjunction or in opposition there is an eclipse. This is partly due to the lunar orbit being tilted by 5.145deg with respect to the ecliptic and to the precession of the lunar nodes taking 18.6 years to complete a full orbit. In fact, total solar eclipses are quite difficult to predict over a certain location based on repeatable cycles since it requires both a precision of under 1/20 degrees of arc and a discernible pattern of occurrences (Odenwald) since the shadow of the Moon on Earth is only 300km across. Lunar eclipses on the other hand are quite the opposite, with the shadow of the Earth being 12,000 km across. In addition, following a record of 1,000 years of possible total solar eclipses between 1,207 BCE to 1 BCE over Ancient Egypt, no discernible pattern can be noticed. On contrast, lunar eclipses seem to repeat every 135 and 223 synodic months. Over a large time span, by looking closely and improving their methods for determining the position of the Moon and planets, ancient astronomers found that the Moon intersects the ecliptic in two points called nodes: the ascending node that the Moon crosses when it passes over the ecliptic, and the descending node, that the Moon crosses when it passes under the ecliptic. Ancient astronomers probably noticed that eclipses occur only when the Moon is near one of these nodes. The time interval between two consecutive Moon passes through one of the two nodes received the name of draconian period and has the value M = 27.21221780 days. Interestingly, the term draconian has a mystical origin and Rosette of spiral diagrams and solar eclipses Fig. 1 – The position of the Sun, the Moon, and the Earth necessary to produce a solar eclipse (a) and a lunar eclipse (b) Olenici (1999)

50 is related to the ancestry conception of which, at eclipses, the Sun or Moon are swallowed by dragons placed at the respective points. As in Latin, the dragon is called draco, the respective drones or called draconian, and the time required by the Moon to return to the same draconian point, draconian period. In Hindu mythology there are two demons Rahu, when the Moon transit ascending node, and Ketu, when the Moon transit descending node. In the Romanian mythology, guilty of the disappearance of the Sun and the Moon, there are werewolves, three-headed demons that appear if the women purr at night without light (Olenici, 2016). Through visual observations, it has been found that eclipses do not occur every time the Moon passes through the draconian points. It has been observed that eclipses only occur if both conditions are met at once, that is, the Moon is at the conjunction or opposition and crosses or is very close to one of the orbital nodes. Therefore, the period after which the eclipses can be repeated will have to be a period in which S and M are encompassed several times. Calculations show that 242.M = 6,585.45670 days and 223.M = 6,585.32115 days. If we make the transition from days to years, that is to divide the period above to 365.25 (the number of days in a calendar year) we obtain a duration of 18 years and 11 days, and 8 hours which represents exactly the duration of the Saros cycle discovered by the Chaldeans (Todoran, 1977). In ancient times the values of the synodic and draconian periods did not have the current accuracy, but this does not greatly influence the duration of the Saros cycle established at 18 years. By observing the eclipses within a Saros cycle, the Chaldeans could predict with satisfactory accuracy how the eclipses of the next Saros cycle would succeed. Since the orbit of the Moon is inclined to the ecliptic, the eclipses take place only if the position of the nodes of the lunar orbit is below 16.5deg from the Sun on the ecliptic. When this angular distance falls below 10.5deg the eclipse becomes total (Olenici, 2016). In Figure 1 (a) we can see the necessary position of the Moon in its orbit and of the Sun on the ecliptic when a solar eclipse occurs. Similarly, in Figure 1 (b), we can see the position of the Moon in its orbit and the shadow of the Earth on the ecliptic when a lunar eclipse occurs (N-nodes, S-Sun, M-Moon, E-Earth, U-umbra, P-penumbra). These situations are repeated after half a year. These positions are called eclipse seasons and last between 31 and 37 days. During this time, the Moon can partially or totally cover the Sun. Currently, researchers believe that the Chaldean astronomers could have predicted lunar eclipses based on the 223 synodic month cycle (Nickiforov, 2011). Considering that in most cases eclipses occur in pairs, a Sun eclipse paired a Moon eclipse at 14 days intervals, the Saros cycle discovered by the Chaldeans and used to predict the lunar eclipses, is also valid for the provision of the solar eclipses. We should note that the points on Earth that see the repetition of a solar eclipse are displaced from the previous ones about 120deg westward. The cause, the duration of a Saros contains a fractional part, equal to about a third of the day (8 hours). Because of this, a solar eclipse recurs in a place on the Earth’s Surface, in roughly similar conditions, after a series of three Saros cycles, that is, after 54 years and 34 days, but moved further north if the Moon passes through the ascending node and moving further south if the Moon passes through the ascending node. This interval of three Saros cycles is named triple Saros or exeligmos (Greek for “turn of the wheel”). All eclipses that are chained by a Saros cycle form a Saros series which lasts between 1200–1500 years and contains 68–75 Saros cycles, after which the Sun rises from the range of 33deg near the nodes of the lunar orbit (eclipse season) and thus eclipses can no longer occur. The term of Saros series was introduced by the Dutch astronomer G. van den Bergh (FlatEarth.ws). ECLIPSES INSIDE A SAROS CYCLE AS A TEMPORAL CIRCLE: THE SAROS YEAR Considering that the eclipses are repeated cyclically, we represented a Saros cycle in the form of a single circle (Figure 2) that presents the months and days of a calendar year named temporal circle or Saros year. The symbols of solar eclipses are as follow: total eclipses are represented by dots, partial eclipses by crescents, annular eclipses by two concentric circles and hybrid eclipses by stars. For example, let us consider the Saros cycle between January 26, 1990, and September 11, 2007. We choose this cycle because it includes the total solar eclipse of August 11, 1999, whose bandwidth crossed Romania. We give every eclipse a serial number as follows: 1–26.01, 1990; Fig. 2 – The order of the eclipses in the eclipse temporary circle of Saros cycle between January 26,1990 – September 11, 2007.