BBC Sky at Night November_2020

8 GLITTERING STAR CLUSTERS: TAKE A TOUR

Explore their science and splendour this month

Sky at Night#186NOVEMBER2020
THE UK’S BEST SELLING ASTRONOMY MAGAZINE

SPECIAL REPORT

LIFE ON
VENUS?

We assess the evidence and
ask, if there really is life
what would it be like

THE ISS AT 20

After two decades of occupation,
what next for the orbiting outpost?

MAKE THE MOST OF MARS

Now past opposition, the Red Planet
remains an unmissable sight

TICKET TO RIDE THE QUEEN'S AEROPLANE DOUBLE STAR DANCE

Want to get to space? And other wide-field sights The exoplanets in orbit

Here's how you can to see with binoculars around binary suns

CONNECT
YOUR PHONE
AND TAKE A
GUIDED TOUR
OF THE
UNIVERSE

DOCK Your smartphone to analyse the night
sky using real time image capture to calculate
your position
LAUNCH The included StarSense App, then
follow the guiding arrows until the bullseye turns
green
OBSERVE Your selected object in the telescope
eyepiece and discover stars, planets and more

Model shown StarSense Explorer LT 114AZ
RRP £199.99 (smartphone not included)

Other models available: StarSense Explorer LT 80AZ,
DX 102AZ and DX 130AZ

For more information visit celestron.com/ssetelescopes Contact Celestron at [email protected]

Welcome HOW TO CONTACT US

Is there life on Venus? We take Subscriptions, binders and back issues
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As we were working on this issue the news broke of a remarkable
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question naturally became, is this a biomarker – a sign of life on Venus?
Editorial enquiries
Our news editor Ezzy Pearson takes a close look at this sensational +44 (0)117 300 8754
story in ‘Bulletin’ on page 10, and the diligent work put in by the research 9.30am–5.30pm, Mon–Fri
WHDP IRU WKHLU GHWHFWLRQ RI SKRVSKLQH WR PHHW VFLHQWLƅF VFUXWLQ\ Advertising enquiries
Then on page 29, science writer Mark Garlick gives more context to the +44 (0)117 300 8145
observation, reminding us that astronomers, including Carl Sagan, have
long suggested Venus’s clouds could harbour life. On page 18, Chris Lintott Print subscription enquiries
JLYHV D IDVFLQDWLQJ LQVLJKW LQWR ƅOPLQJ The Sky at Night’s September www.buysubscriptions.com/contactus
episode, which aired the day the news was released, and in which he Digital subscription enquiries
interviewed the project’s lead author Professor Jane Greaves. www.buysubscriptions.com/contactus
Editorial enquiries
Elsewhere this issue, we cover another planet that’s the focus of the [email protected]
search for life, Mars, on page 66. Paul Abel’s feature doesn’t look at science
being done there, however, but at the Red Planet’s remarkably good
Subscription enquiries
position in the night sky. Its best opposition for a decade may have UK enquiries: FREEPOST IMMEDIATE
passed, but it’ll still be a great target to observe for many months to come. MEDIA (please write in capitals)
Overseas enquiries: PO Box 3320,
And on page 61 we celebrate a milestone for the International Space 3 Queensbridge, Northampton
Station – its 20th anniversary of crewed operations. Nisha Beerjeraz-Hoyle NN4 7BF, UK
looks back at its key moments from the past two decades and ponders Editorial enquiries
what comes next in its story, as it reaches a pivotal moment. BBC Sky at Night Magazine, Immediate
Media Co Bristol Ltd, Eagle House,
Enjoy the issue! Colston Avenue, Bristol BS14ST

Chris Bramley, Editor Become an Insider

PS Our next issue goes on sale on 19 November 2020. The more we know about what
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Sky at Night – lots of ways to enjoy the night sky…

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November 2020 BBC Sky at Night Magazine 3

29

CONTENTS C = on the cover Reviews

86 ZWO ASI 1600GT

Features Regulars Mono camera
6 Eye on the sky
29 Microbial life on Venus. 10 Bulletin 90 Altair Starwave
C What are the chances? 16 Cutting edge C
18 Inside The Sky at Night 110ED-R refractor
We look at the evidence of 20 Interactive
lifeforms in Venus’s clouds, now 23 What’s online 94 Books
phosphine has been detected 25 Field of view
26 Subscribe to BBC Sky 96 Gear
35 Galactic gatherings
at Night Magazine The Sky Guide 16-PAGE
C Join our tour, as we select some 72 Explainer C CENTRE
of the most striking star clusters to 74 DIY Astronomy PULLOUT
observe in November’s night sky 98 Q&A: an ISS astronaut
COVER MAIN IMAGE: MARK GARLICK. THIS PAGE: © PLANET-C PROJECT TEAM, HANNES 44 Highlights
BACHLEITNER/CCDGUIDE.COM, @THESHED_PHOTOSTUDIO, D. PEACH/E. ENZMANN, 61 20 years of the ISS
NASA X 3, KONSTANTIN SHAKLEIN/ALAMY STOCK PHOTO, BBC 46 The big three
C How the ISS is preparing for a new
generation of space explorers 48 The planets

50 November’s all-sky chart

52 Moonwatch

53 Comets and asteroids

53 Star of the month

Astrophotography 54 Binocular tour C
76 Capture
66 The Red Planet, an 78 Processing 55 The Sky Guide challenge
C ember growing bright 80 Gallery
56 Deep-sky tour
Mars may be past opposition,
but there’s still plenty to see 58 November at a glance

4 BBC Sky at Night Magazine November 2020

New to astronomy? Extra content

To get started, check out our guides and glossary at ONLINE
www.skyatnightmagazine.com/astronomy-for-beginners
Visit www.skyatnightmagazine.
35 com/bonus-content/E6AK8KT/
to access this month’s selection
of exclusive Bonus Content

NOVEMBER
HIGHLIGHTS

Interview: 20 years of the ISS

Veteran NASA astronaut Jeff Williams discusses the
history and future of the International Space Station.

66

86
61

72 Life on Venus? Audiobook: Diary of an
A Sky at Night special Apprentice Astronaut
This month’s contributors
The team get exclusive Listen to chapters from
access to UK astronomers Samantha Cristoforetti’s
who have made a huge new book, revealing
discovery in the search the story behind her
for life beyond Earth. 200 days on the ISS.

Nisha Will Gater Ezzy Pearson The Virtual Planetarium
Beerjeraz-Hoyle
Astronomy journalist News editor Pete Lawrence and Paul Abel guide us through
Space writer the best sights to see in the night sky this month.
“I’ll never tire “While a trip
“The ISS is of exploring to space is
remarkable, open star still beyond
and it is a real clusters at P\ ƅQDQFHV
privilege to the eyepiece and this at the moment, it was
share a glimpse of its month we’re spoilt with fun to dream about how
history and the value it so many to choose I could visit the Moon…
has contributed towards from across the sky”. if only I had the spare
the next chapter of Will takes us on a tour billion dollars.” Ezzy
space exploration.” of some of November’s looks at the options
Nisha celebrates 20 most impressive star for getting a ride
years of the ISS, page 61 clusters, page 35 into space, page 72

November 2020 BBC Sky at Night Magazine 5

ESA/HUBBLE & NASA/J. LEE AND THE PHANGS-HST TEAM; ACKNOWLEDGMENT: JUDY SCHMIDT (GECKZILLA) STAR
SPANGLED
SPIRAL

NGC 2835 is part of a galactic quest to
explain how cold gas creates hot stars

HUBBLE SPACE TELESCOPE, 14 SEPTEMBER 2020

This beautiful face-on spiral galaxy is NGC 2835, found 35 million
lightyears away near the head of the constellation of Hydra,
the Water Snake. Stretching up to 65,000 lightyears across, more
than half the width of the Milky Way, its four distinct arms and
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It’s within these many pockets of cold, dense gas that clusters of
hot, new stars are born. The cold gas is also fuelling the spiral’s
supermassive black hole, up to 10 million times more massive than
our Sun, at the centre of this galaxy.

NGC 2835 is one of over 100,000 star-forming regions and
gas clouds outside our Milky Way that are being catalogued for
PHANGS-HST project. This unique combined Hubble and ALMA
study aims to explore the relationship between young stars, cold
molecular gas and the structure of galaxies. Its conclusions will
help inform the target list for the long-awaited James Webb
Space Telescope, launching next year.

MORE ONLINE

A gallery of these and more
stunning space images

6 BBC Sky at Night Magazine November 2020

September 2020 BBC Sky at Night Magazine 7

ESA/HUBBLE & NASA/W. BLAIR, NASA/ESA, A. SIMON (GODDARD SPACE FLIGHT CENTER) AND M. H. U Ripple effect
WONG (UNIVERSITY OF CALIFORNIA/BERKELEY) AND THE OPAL TEAM, SOFIA / NASA/JPL-CALTECH/L.
ALLEN (HARVARD-SMITHSONIAN CFA) & GOULD’S BELT LEGACY TEAM, ALMA (ESO/NAOJ/NRAO) ESO/ HUBBLE SPACE TELESCOPE,
EXETER/KRAUS ET AL, ALMA (ESO/NAOJ/NRAO) DECIN ET AL 28 AUGUST 2020

This gossamer veil, 2,400
lightyears away in Cygnus, is
the ethereal remains of a star’s
death around 20,000 years ago.
Imaged by the Hubble Space
Telescope, this is just a small
section of the blast wave
created when a colossal star,
20 times larger than the Sun,
went supernova. It has since
expanded 60 lightyears from
the blast’s centre and continues
to travel outwards at 350km/s.

Y Jupiter in
a new light

HUBBLE SPACE TELESCOPE,
25 AUGUST 2020

This Hubble image combines
near-infrared, visible and
ultraviolet light to reveal Jupiter
in pastel shades. In its multi-
wavelength livery, the blue areas
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the planet, while the atmosphere
at higher altitude appears red. It
also reveals a new, bright white,
extended storm to the upper left,
which erupted on 18 August and
is travelling at 560km/h.

8 BBC Sky at Night Magazine November 2020

Y Feeding the stars

SOFIA/SPITZER SPACE TELESCOPE,
20 AUGUST 2020
Looking like the strokes of an artist’s brush
on the celestial canvas, these lines are
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into an area of new star formation, the
Serpens South star cluster. They are
revealed by the HAWC+ infrared instrument
on board the SOFIA airborne observatory,
which is able to observe dust grains as they
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V Blasted bloom

ATACAMA LARGE MILLIMETER/
SUBMILLIMETER ARRAY,
21 SEPTEMBER 2020
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new ALMA image shows something far less
serene: stellar winds raging up to a million
times stronger than those from our own
Sun. They are blasting from red giant star
R Aquilae, one of several red giants whose
winds have been shown to blow out not
spherically as expected, but in irregular
shapes. One theory is that the patterns
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giant planet nearby.

Y A tilted disc

ALMA/VERY LARGE TELESCOPE, 3 SEPTEMBER 2020
While all the planets and moons in our Solar System orbit on nearly the same plane, things
are a bit different in triple-star system GW Orionis. Images from ALMA (top) and ESO’s
Very Large Telescope (bottom) show that it has highly skewed inner rings of gas and grit,
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that groups of stars can warp and tear apart their protoplanetary discs.

November 2020 BBC Sky at Night Magazine 9

The latest astronomy and space news, written by Ezzy Pearson

BULLETIN

Chemical linked to life found on Venus

The clouds above the planet contain phosphine, which is produced by bacteria on Earth

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10 BBC Sky at Night Magazine November 2020

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The Sky at Night

November 2020 BBC Sky at Night Magazine 11

BULLETIN

Spotless: during solar minimum in 2019 no
sunspots are visible on the Sun’s surface (left),

in stark contrast to solar maximum in 2014

December 2019 July 2014

New solar cycle begins

Sunspot activity is likely to remain below average for some time to come

NASA/SDO/JOY NG, NASA’S GODDARD SPACE FLIGHT CENTER, NASA, ESA/ROSETTA/NAVCAM Solar Cycle 25 KDV RIƅFLDOO\ EHJXQ $IWHU D PRYHPHQW FUHDWHV LWV PDJQHWLF ƅHOG EXW equipment, as well as satellites and the
year and a half with barely any sunspots, a as the Sun spins it churns up this plasma. communications and location services
group of astronomers, known as the Solar Over time, this motion drags the magnetic that rely on them. For NASA, there is the
&\FOH 3UHGLFWLRQ 3DQHO KDYH UHFHQWO\ ƅHOG OLQHV DZD\ IURP WKH SROHV WRZDUGV WKH added concern that peak activity will fall
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“We keep a detailed record of the few the physical basis of the solar cycle. with the Artemis program.
tiny sunspots that mark the onset and
rise of the new cycle,” says Frédéric Clette, If the sunspots continue to follow their The panel expect this cycle to be
part of the panel and head of the World current trend, the panel predict the peak of relatively weak, as solar activity has been
Data Centre for the Sunspot Index and VRODU DFWLYLW\ LQ &\FOH ZLOO RFFXU VRPH WUHQGLQJ GRZQZDUGV VLQFH WKH V EXW
Long-term Solar Observations (SILSO). time between November 2024 and March this might not be enough to be risk free.
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that we can determine the tipping point could mean bigger and brighter auroral space weather,” says Doug Biesecker,
between two cycles.” displays here on Earth. co-chair of the panel and a solar physicist
at NOAA’s Space Weather Prediction
Though astronomers track the cycle on It’s important to know when such solar Center. “The Sun’s impact on our daily lives
the Sun’s surface, its origin stems from the outbursts will be particularly intense as is real and is there.”
motion of plasma deep within our star. This their radiation can damage space www.sidc.be/silso

12 BBC Sky at Night Magazine November 2020

NEWS IN

BRIEF

ILLUSTRATION WD 1856 b, a potential
Jupiter-sized planet, orbits

a smaller white dwarf

Planet survived star’s death

The world is seven times larger than the white dwarf star it orbits

A giant planet around a white layers. “The white dwarf hours, but it is likely to have Comet aurora
dwarf could have survived the creation process destroys been further out when the star
star’s death throes, according nearby planets, and anything was in its red giant phase. Ultraviolet aurora have
to the latest observations with that later gets too close is been seen dancing around
the Transiting Exoplanet usually torn apart by its “We’ve seen that planets FRPHW 3 &KXU\XPRY
Survey Satellite (TESS). immense gravity,” says Andrew could scatter inward, too, but *HUDVLPHQNR Ś WKH ƅUVW WLPH
Vanderburg of the University of WKLV DSSHDUV WR EH WKH ƅUVW such a light show has been
A white dwarf is the remnant Texas, Austin, who led the work. time we’ve seen a planet that seen around a celestial object
left behind after a Sun-like star made the whole journey other than a planet or moon.
runs out of fuel, becomes a red 7KH SODQHW :' E LV VR intact,” says Vanderburg. Recently analysed images
giant and then loses its outer FORVH WKDW LW RUELWV LQ RQO\ exoplanets.nasa.gov/tess taken by the Rosetta
spacecraft show the solar
Artemis’s return to the Moon mapped out wind interacting with the
comet’s coma to produce
NASA’s planned return to the Moon is ILLUSTRATION Back to the Moon: the aurora.
scheduled to arrive on the lunar surface by 2024. NASA’s Orion spacecraft
The agency recently released its timeline for the is an important part of its Dark skies in NI
Artemis program, which includes landing the
ƅUVW ZRPDQ RQ WKH 0RRQ ZLWK WKH ƅUVW VWDJH Artemis program The Dark Sky Observatory
$UWHPLV , GXH WR Ɔ\ LQ and Visitor Centre in the
Davagh Forest, Mid Ulster
7KH ƅUVW ƆLJKW ZLOO EH DQ XQFUHZHG WHVW XVLQJ LV ƅQDOO\ GXH WR RSHQ RQ
the Space Launch System to send the Orion 2FWREHU DIWHU EHLQJ
Multi Purpose Crew Vehicle to the Moon and GHOD\HG GXH WR WKH &29,'
EDFN WR FRQƅUP ERWK DUH VDIH IRU KXPDQV pandemic. The forest is
$UWHPLV ,, ZLOO WKHQ UHSHDW WKH ƆLJKW LQ 1RUWKHUQ ,UHODQGŝV ƅUVW
with astronauts onboard. accredited International
Dark Sky Park.
If these go to plan, NASA will launch Artemis III
in 2024, which will send a lander down to the A Pi-fect planet
lunar South Pole. Subsequent missions will use
a space station NASA plans on building in orbit A ‘pi-planet’ has been
around the Moon, known as the Lunar Gateway, discovered zipping around its
but it may not be ready in time for Artemis III. KRVW VWDU RQFH HYHU\
days. The planet has a radius
ş:HŝUH JRLQJ EDFN WR WKH 0RRQ IRU VFLHQWLƅF DERXW WLPHV WKH VL]H RI
GLVFRYHU\ HFRQRPLF EHQHƅWV DQG WR LQVSLUH Earth’s, but it isn’t thought to
a new a generation of explorers,” says Jim be habitable as its tight
Bridenstine, NASA’s administrator. “As we build orbit means the surface
up a sustainable presence, we’re also building temperature is expected to
PRPHQWXP WRZDUG WKRVH ƅUVW KXPDQ VWHSV RQ EH DURXQG z& Ś KRW
the Red Planet.” enough to bake an actual pie.
www.nasa.gov

November 2020 BBC Sky at Night Magazine 13

NEWS IN BULLETIN

BRIEF M87’s glittering black heart

Astronomers have tracked a black hole shimmering for over a decade

Out of alignment The Event Horizon Telelesope image of M87 them, astronomers have
has helped researchers to analyse archival data gone back over the data
The Solar System could taken by prototype networks
be aligned along more than The black hole at the heart known as the Event Horizon that preceded the EHT to
just the ecliptic (the plane RI JDOD[\ 0 DSSHDUV WR Telescope (EHT) imaged extract earlier images of
that the planets orbit in). be glittering. The galaxy the shadow of its central the black hole. In doing so,
A recent look at the orbits ƅUVW PDGH KHDGOLQHV LQ black hole. Armed with they created a timeline of
of long period comets when a network of telescopes the EHT image to guide its appearance over the
revealed that many of last decade. The analysis
them appear to line up showed that while the ring
along a newly discovered stays the same size, its
‘empty ecliptic’, which is brightest point dances
RIIVHW E\ DURXQG Ō around the edge, giving it a
shimmering appearance.
Nobel prize for
black holes “Studying the region
will be crucial for a better
The 2020 Nobel Prize in understanding of how black
physics has been awarded holes accrete matter and
to three scientists launch relativistic jets,” says
investigating black holes. Thomas Krichbaum from
The award will be shared the Max Planck Institute for
between mathematician Radio Astronomy.
Roger Penrose for his eventhorizontelescope.org
theoretical work on how
they form, and astronomers Potential Martian lake and companion ponds
Andrea Ghez and Reinhard
RWARNICK/ISTOCK/GETTY IMAGES, EHT COLLABORATION, NASA/JPL-CALTECH/MSSS, NASA/JPL- Genzel for their discovery Water lakes could be lying beneath What lies beneath? An image of
CALTECH/UNIVERSITY OF ARIZONA/LPG/CNRS/UNIVERSITY OF NANTES/SPACE SCIENCE INSTITUTE of the black hole at the Mars’s ice caps, according to the Mars’s north polar region, made
heart of the Milky Way. latest radar analysis of the planet. with Mars Global Surveyor data

China’s reusable Hints of a huge lake 1.5km “We don’t know exactly what is in this water,”
spaceplane underneath the Red Planet’s poles VD\V 2URVHL ş:H GRQŝW NQRZ WKH FRQFHQWUDWLRQ
ZHUH ƅUVW XQFRYHUHG EDFN LQ of salts, which could be deadly to life.
China successfully 7KH ƅQG SURPSWHG 5REHUWR 2URVHL [Alternatively] these lakes could have been
launched a prototype from the National Institute for providing a Noah’s Ark that could have allowed
reusable spacecraft on Astrophysics in Bologna, Italy, and life to survive even in present conditions.”
4 September. It remained his team to re-examine data of the www.esa.int
in low-Earth orbit for region taken by ESA’s Mars Express
two days before landing orbiter from 2010 to 2019. These
back on Earth. However, UHYHDOHG VHYHUDO UHƆHFWLYH ƆDW DUHDV
images or details about EHQHDWK WKH VXUIDFH WKDW FRQƅUP
the spacecraft have not WKH HDUOLHU ƅQG ZLWK WKH DGGLWLRQ
EHHQ RIƅFLDOO\ UHOHDVHG of three smaller ponds.
leading many to question
its potential purpose. Whether or not the areas are
actually liquid, however, has split planetary
scientists. While similar observations on Earth
have revealed subglacial lakes, these would
need to somehow stay liquid at temperatures
of –70ºC. This could be possible if they were
extremely salty.

14 BBC Sky at Night Magazine November 2020

90º W 0º
Leading Saturn
hemisphere facing

90º E North
Trailing Pole
hemisphere
South
Icy Enceladus’s Pole
fresh faces
November 2020 BBC Sky at Night Magazine 15
Enceladus, one of Saturn’s icy moons, appears to have a
youthful glow around its northern pole, according to newly
processed images from NASA’s Cassini spacecraft.

The spacecraft’s infrared cameras revealed areas of fresh ice
(shown in red) across the moon’s surface. While it’s no surprise
WR ƅQG WKH VRXWK SROH LV UHVXUIDFHG Ś WKH DUHD LV KRPH WR VHYHUDO
cracks, known as ‘tiger stripes’, where water sprays up from
EHORZ WKH VXUIDFH Ś WKH LPDJHV DOVR UHYHDOHG VXEWOHU SDWFKHV RI
new ice in the northern hemisphere. “Thanks to these infrared
eyes, you can go back in time and say that one large region in
the northern hemisphere also appears young and was probably
active not that long ago, in geologic timelines,” says Gabriel
Tobie, from the University of Nantes, who helped write the paper.
www.jpl.nasa/gov

Our experts examine the hottest new research

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16 BBC Sky at Night Magazine November 2020

CUTTING EDGE

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November 2020 BBC Sky at Night Magazine 17

The Sky at Night TV show, past, present and future

INSIDE THE SKY AT NIGHT

The Sky at Night’s schedule is usually only moved for major space Þ Clockwise from
missions, but a possibility of life on Venus proved an important
exception. Chris Lintott recalls how the show reacted to the news top left: Chris
Lintott meets
BBC X 4, JEREMY SUTTON-HIBBERT/ALAMY STOCK PHOTO,Have you imagined where you’d be when the discovery, we quickly moved the show, something Jane Greaves from
ESO/M. KORNMESSER you hear that aliens have turned up? we normally only do for major space missions. And Cardiff University
I heard about the amazing discovery so producer Toby, assistant producer Angel and I to discuss her
featured in this month’s programme found ourselves wandering the corridors of a nearly findings about
while sitting in my kitchen, speaking to deserted Cardiff physics department, chatting about traces of phosphine
an old friend of the programme, Chris life on Venus and the wonders of phospine. in the atmosphere
North, on the phone. of Venus; chemist
Chris was calling to tell me that a team led by his Persistence pays off William Bains
colleague Jane Greaves in Cardiff had found what gives a musical
they thought was a biosignature – a sign of life – in the I’ve known Jane a long time and it was so exciting to slant to Venusian
atmosphere of Venus. What he actually said to me was, see her pride in her team and their discovery, and I life; Emily Drabek-
“Can you speak Venusian?” It’s the title of one of Patrick marvel at the perseverance she showed in pursuing a Maunder, from the
Moore’s books covering ‘independent thought’ – UFOs, project through numerous rejections by observatories Royal Observatory
a vicar who thinks the Sun is cold, that sort of thing. and referees. But it was still bizarre to be sitting in Greenwich,
It quickly became clear that, unlike the man who in VRPHRQHŝV RIƅFH DQG DVNLQJ Ś RQ FDPHUD LQ D PDWWHU RI discusses the
one archive episode explained to Patrick that Jesus fact tone – “Have you found life?” Jane’s answer was project’s origins;
came from Venus, this story was credible. But it was that she was worried about the sulphuric acid content Jane Greaves
due to be released the day after The Sky at Night of the clouds, but it was clear that the idea that this shares the data
was to be broadcast. Because of the importance of might be life was the thing which had pushed her she used to trace
through the years of hard work. the presence
of phosphine

18 BBC Sky at Night Magazine November 2020

INSIDE THE SKY AT NIGHT

Prof Chris Lintott We also talked to chemist William Bains, who among the clouds? If life exists on Venus, shouldn’t it
is an astrophysicist volunteered to bring his guitar to sing us a song about be everywhere? Or – and I confess the beer made us
and co-presenter Venusian life, and melted all sorts of things, including concentrate rather less on this possibility – could there
on The Sky at Night bread, with concentrated sulphuric acid. Meanwile, be some unknown chemistry at work, which the team’s
Emily Drabek-Maunder from the Royal Observatory models haven’t accounted for.
Greenwich, told us about the project’s origins and
then, after a long day and the cameras put away, A discovery like this is exciting not because it solves
Chris North and I sat with takeaway beer on the grass a problem, but because it raises a million questions.
outside Cardiff Castle, and let our imaginations run. That’s why it’s fun, and why I’m so proud that The
Sky at Night was able to report on a surprising and
Could the detection of phosphine mean sending fascinating new result.
balloons to sail the high clouds of Venus’s atmosphere,
looking for life? Could this life be the remnant of some > Read more about the Venus discovery in our
grand old Venusian civilization, reduced to clinging on feature on page 29 and in ‘Bulletin’ on page 10

We need you!

Have your questions NOVEMBER
answered on the show
Beyond Venus
< Astronomer Royal: Sir Martin Rees
Following the news about possible signs
will be featured on the special episode of microbial life in the clouds of Venus, the
of The Sky at Night in December team report on the discovery from the
Royal Observatory Greenwich. Chris and
forward to the next 10 years and discuss 0DJJLH ƅQG RXW DERXW IXUWKHU UHVHDUFK
the challenges, frontiers and and look into the wider search for life in
opportunities that lie ahead. the Solar System, focusing on Mars, Titan,
Enceladus and Europa, as well as biological
The programme will feature interviews signatures on planets orbiting distant stars.
with some of the leading astronomers
in the country, including the Astronomer Four, 8 November, 10pm (first
Royal, Sir Martin Rees (left).
repeat Four, 12 November, 7:30pm)
The Sky at Night is offering viewers
the chance to have their question put Check www.bbc.co.uk/skyatnight
to one of the guests on the programme.
for more up-to-date information
Your question could relate to any
Do you have a question you’d like area of astronomy, looking back over Þ After Venus, could a similar discovery be
put to one of the top astronomers the past decade, or forward into the
in the country? future – whether it’s the exploration made on a planet beyond our Solar System?
of our own Solar System, hunting for
The December episode of The Sky at signals from the edge of the Universe
Night will be a one-hour special looking or anything in between.
at the major advances, achievements
and discoveries in astronomy over the If you would like your question to
past decade. It will also be looking be considered, please send it to:
[email protected]

Please include your name, address
and contact number.

November 2020 BBC Sky at Night Magazine 19

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Northern Constellations, VHFRQG H[SRVXUH DW ,62 ,WV WZR
Heather Couper and Nigel SDQHOV DUH HDFK FRPSRVHG RI H[SRVXUHV
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and a planisphere for the WRJHWKHU LQ 3KRWRVKRS
night skies as they appear Rich Addis, via email
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A truly touching message and photo, Rich! A dark
Winner’s details will be passed on to night sky and the glittering stars of our Galaxy
Octopus Publishing to fulfil the prize are sometimes just the thing to put things back
in perspective. – Ed.

Tweet Inorganic theory 1. Greaves, Jane S., et al., “Phosphine
gas in the cloud decks of Venus”,
Allan D 7KH UHFHQW GLVFRYHU\ RI SKRVSKLQH LQ WKH Nature Astronomy (2020): https:
#DGXII\ Ť 6HS 9HQXVLDQ DWPRVSKHUH SXEOLVKHG LQ Nature //doi.org/10.1038/s41550-020-1174-4
3ODQHW #Mars shining bright last Astronomy1 SURPSWHG XV WR VXJJHVW DQ 2. https://en.wikipedia.org/wiki/
night DVWURQRP\ LQRUJDQLF K\SRWKHVLV IRU WKH RULJLQ RI WKLV Schreibersite
DVWURSKRWRJUDSK\ # JDV *DODFWLF SKRVSKRUXV H[LVWV DV PL[HG 3. Tanaka, Tatsuhiko, et al. “Simultaneous
VN\DWQLJKWPDJ 7KH3KRWR+RXU LURQ QLFNHO SKRVSKLGHV ZKLFK DUH determination of phosphorus, sulfur and
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PHWHRULWHV 7KHVH DUH FUHGLWHG ZLWK and gas chromatography”, Analytical
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WE ASKED: What do you make of the recent LPDJH WKURXJK DQ 6&7 LV UHYHUVHG OHIW WR ULJKW 6R IRU WHUUHVWULDO
discovery of evidence of microbial life on Venus?
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November 2020 BBC Sky at Night Magazine 21

BBC Sky at Night Magazine is published by Immediate INTERACTIVE
Media Company Bristol Limited under licence from
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EDITORIAL lewissorcha • 24 September

Editor Chris Bramley Dramatic scene Miners cottage under the milky way…
Art Editor Steve Marsh Transported back in time under the
Production Editor Neil McKim > I looked out of the window on starry night sky, this ruin had a capability
News Editor Ezzy Pearson 27 September and saw this! I think the of coming alive once more. I could almost
Staff Writer Iain Todd clouds must be contrails, and the VPHOO WKH WXUI ƅUH DQG FRXOG KHDU WKH
Reviews Editor Paul Money Moon, Jupiter and Saturn were also on sound of a man coughing and calling in a
view. I grabbed my Sony DSC-HX60 dog for the night as the light spilled out
CONTRIBUTORS compact camera and got this photo from the doorway in which he stood.
from the bedroom window. Can’t beat the beauty of a clear starry
Paul G Abel, Nisha Beerjeraz-Hoyle, Lewis Dartnell, Roger Samworth, Nuneaton sky...think we should all be prescribed one.
Glenn Dawes, Mark Garlick, Will Gater, Tim Jardine, #nighttimewildlifewonder #midwales
Sandra Kropa, Pete Lawrence, Chris Lintott, Chris North, Light concerns #nighttimewalks #skyatnight
Gary Palmer, Steve Richards, Niamh Shaw, Steve Tonkin,
Paul Truelove, Mark Whalebone, Jane Williamson, May I compliment you and Dani
Jenny Winder, Paul Wootton, Brandon Yoshisawa Robertson on a very good article on light
pollution (‘Field of View’, October issue).
ADVERTISING SALES Could I be bold enough to ask her and her
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Advertising Manager Sam Jones +44 (0)117 300 8145, to try and teach them a few things. My
[email protected] back garden is overlooked by two or three
Inserts Laurence Robertson +353 (0)87 690 2208 offending streetlamps that plague my
enjoyment of astronomy. It’s a good job
PRODUCTION your magazine drops through the
letterbox each month, as I’ve not seen
Production Director Sarah Powell a decent night sky yet!
Production Coordinator Lauren Morris Tony Noble, Rugby, Warwickshire
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Ad Designer Parvin Sepehr
Reprographics Tony Hunt, Chris Sutch For the last quarter century Manchester Þ Video links: Manchester Astronomical
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LICENSING the Godlee Observatory, which we have Society makes use of technology
been closely associated with since its
Director of Licensing and Syndication Tim Hudson opening in 1902 atop the Sackville Building Our monthly public lectures, dating
International Partners’ Manager Anna Genevier at the University of Manchester. Since back over a century, with a short gap
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MARKETING to lockdown, with all meetings cancelled. affected by lockdown. Our last guest
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Press and PR Manager Emma Cooney counterbalancing 12-inch Newtonian built underway to employ video conferencing
by Grubb of Dublin, were the last of only for our autumn lecture season.
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to maximise the use of a small teaching Manchester Astronomical Society
Publisher Jemima Dixon observatory. The refractor could have > www.manastro.org
Managing Director Andy Healy been used to observe and photograph
Group Managing Director Andy Marshall Comet NEOWISE, but it wasn’t to be.
CEO Tom Bureau
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22 BBC Sky at Night Magazine November 2020

COVID-19 We pick the best astronomy events and resources available online this month

Thsiosenlmleinocaetngeteadhivnowennelt’ysve

PICK OF THE MONTH

ONLINE TALKS

Royal Observatory shows
Hosted over Zoom by astro experts,
‘Solar System Discovery’ (above) takes
DQ LQWHUDFWLYH IDFW ƅOOHG WRXU RI WKH
Solar System, while ‘Space Queries and
Theories’ are short talks after which
you can ask space-related questions.
Suitable for ages 7+.
www.rmg.co.uk/whats-on

Deep Astronomy Þ Mars in focus: this year’s National Astronomy Week celebrates the Red Planet
This long-running YouTube channel
tackles tons of heavyweight astronomical National Astronomy Week
subjects and features discussions
with a range of expert guests. 14–22 November 2020
www.youtube.com/user/
© NATIONAL MARITIME MUSEUM/LONDON, STEVE MARSH tdarnell/featured Although National Astronomy Week sessions aimed at young people organised
(NAW) 2020 has had to move online, by science outreach organisations, plus
RADIO it’s still a great chance to focus on and online talks by astronomical societies.
celebrate the star of the show: Mars.
Astro Radio Having just passed its best opposition for With interest in the planet already
Featuring astronomy chat, science news years, the Red Planet will be a high and KLJK WKDQNV WR WKH ƆXUU\ RI 0DUV PLVVLRQV
and eclectic music throughout the week, bright feature of early evening skies from launched this year, it’s a great time
Astro Radio is available via several music mid-November – perfect for some family to get young observers involved.
streaming services, such as tunein.com. observing time. Whatever equipment you have, get
set up and tuned in – after all, Mars
DOCUMENTARIES NAW organisers plan to live-stream will not be as close again until 2033.
views through amateur and professional Check out astronomyweek.org.uk
A Year in Space telescopes, and provide live expert for event details, Mars info, observing
This 12-part documentary follows veteran commentary. There will also be daily tips, Mars myths explained, and more.
astronaut Scott Kelly’s year-long mission
aboard the ISS with cosmonaut Mikhail Challenger: The Final Flight CITIZEN SCIENCE
Kornienko, testing the effects of living 7KLV QHZ 1HWƆL[ GRFXPHQWDU\ FKDUWV WKH
long-term in zero-g on the human body. tragic disaster that befell the Space Shuttle Help map the skies
ZZZ QHWƆL[ FRP Challenger in January 1986, and how it Like history and know your constellations?
FKDQJHG VSDFHƆLJKW SROLF\ DW 1$6$ Then why not join this citizen science
Horizon 7KH ƅOP IHDWXUHV WHVWLPRQ\ IURP HQJLQHHUV project to spot and label more than 4,000
Take a deep dive in the archives of RIƅFLDOV DQG WKH FUHZPHPEHUVŝ IDPLOLHV historical constellation maps and images
Horizon, the BBC’s long-running science ZZZ QHWƆL[ FRP in Chicago’s Adler Planetarium collection?
programme, and discover episodes bit.ly/maptheskies
covering the height of the Space Race
in the 1960s. bbc.in/2FA67K1

November 2020 BBC Sky at Night Magazine 23

You’re contemplating a photograph of 550 million pixels..
But you can only see a small part of it.

Immersive and interactive
online exploration

vaonis.com/mosaic

Stellina,
the observation station that
simplifies astronomy reveals
one of the Universe’s most
magnificent images.

The amateur astronomer’s forum

FIELD OF VIEW

A cosmic coincidence continues

Since ancient times, comets have been seen as a sign of impending disaster.
During a global pandemic, did Comet NEOWISE keep up with the tradition?

A member of A s long as there have been people was therefore deeply unsettling. No wonder that SEAN LEWIS
Birmingham to worry about what the future comets have always been taken to be harbingers of
Astronomy Society, might hold, humanity has looked catastrophic or pivotal events. It is a seriously weird
Paul Truelove anxiously to the skies for signs and fact, however, that all through recorded history
observes eclipses omens as some sort of indication bright comets have often managed to appear
and occultations about what might lie ahead. just at the very moments that dramatic and
of Jupiter’s moons *LYHQ WKH FRQƅGHQFH DQG FRPSODFHQF\ ZKLFK RXU world-changing circumstances were underway.
with his hand-built VFLHQWLƅF NQRZOHGJH KDV EHVWRZHG LW LV KDUG IRU XV
UHƆHFWRUV KLV today to appreciate the very real fear and serious Perhaps the best-known example is Halley’s
interest sparked by consideration that was accorded to the &RPHW ZKLFK ƆDVKHG DFURVV WKH VNLHV LQ EHIRUH
Brooke Bond Tea’s most transient of unusual natural phenomena. King Harold’s defeat at the Battle of Hastings. The
1957 card series Even relatively rare meteorological happenings, Bayeux Tapestry records this apparition and also
on astronomy such as a lunar halo appearing with the chance shows a number of nobles from King Harold’s court
placement of a planet in it, gave rise to such sayings all looking up and pointing anxiously at the ‘hairy
as, “If the moon is surrounded by a halo, and a star’ which had so silently appeared.
planet stands in it: robbers will rage,” which everyone
then believed. It is widely known that Julius Caesar was murdered
in 44 BC, but what is not so well known is that
The sudden unexpected appearance of an object – when his adopted son, Octavian, organised games
as dramatic and mysterious as a bright comet and a funerary service to deify and celebrate his
father, four months after his death – with incredibly
appropriate timing, the bright comet of 44 BC
& Ś . VKRQH LQ WKH VNLHV DW WKH VDPH WLPH
We have many examples of Roman Denarii silver
coins from this era and there is an example with
the impression of a ‘star’, which has been claimed
to be a representation of Caesar’s Comet.

2Q 2FWREHU 3RSH 8UEDQ ,9 GLHG DQG
amazingly, this important event was also marked
by the appearance of yet another bright comet.
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& 1 LW LV VDLG WKDW WKH 3RSH IHOO LOO RQ WKH
day it appeared and died on the day it disappeared.

Closer to our own times, Mark Twain was born in
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are numerous other examples.

How strange and improbable it is then, that now,
after such a long absence of bright comets from our
VNLHV &RPHW 1(2:,6( VKRXOG VHHPLQJO\ FKRRVH
to continue this same centuries-old tradition and
be at its spectacular best during the very months
WKDW &29,' WRRN KROG DV D SDQGHPLF DQG VZHSW
around the planet. What are the chances? Perhaps,
like the ancients, we should have taken its arrival to
be an omen of things to come.

November 2020 BBC Sky at Night Magazine 25

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MAGAZINE

174GBP

Microbial life on

VENUS

What are the chances?

The detection of phosphine in Venus’s atmosphere has raised
the possibility that it could be produced by lifeforms on the
hellish world. Mark A Garlick considers the evidence

© PLANET-C PROJECT TEAM Does alien life exist in the
clouds above Venus, our
second closest neighbour?

November 2020 BBC Sky at Night Magazine 29

ILLUSTRATION Heaven and hell: at its surface, Venus ...but venture up above the ILLUSTRATION
is a high-pressure furnace that’s hot cloud deck and conditions
enough to melt lead... are far more friendly

A rguably, it is the most inhospitable VXUIDFH <HW WKH DWPRVSKHUH LV QRW TXLWH IHDWXUHOHVV þ Dark mysteries:
terrestrial body in the Solar System. contrast-adjusted photos reveal the presence of dark
The surface temperature, around patches or bands, which are particularly visible at a composite
Ō& LV HQRXJK WR PHOW WLQ ]LQF ultraviolet wavelengths. These so-called ‘unknown ultraviolet and
and lead. The atmospheric ground absorbers’, discovered more than a century ago, infrared image
pressure is 93 bar – like that beneath are caused by mysterious substances that block of Venus from
900m of water on Earth, while the atmosphere is most ultraviolet light and a portion of visible light, Japan’s Akatsuki
choked full of carbon dioxide and clouds that drip rendering these regions comparatively dark. In probe. Scientists
VXOSKXULF DFLG 7KH VN\ EHKDYHV PRUH OLNH D ƆXLG WKDQ August 2019, a team of researchers led by Yeon Joo including Carl
a gas, so dense that the winds can easily move small Lee at the Technical University of Berlin published Sagan have long
rocks. Welcome to hell – otherwise known as Venus. a report in The Astronomical Journal, examining speculated about
how these absorptions affect Venus’s climate. the nature of the
Yet despite this most extreme environment, dark patches shown
scientists have long speculated about life on Venus, “The particles that make up the dark splotches
QRZ RU LQ WKH SDVW Ś DPRQJ WKHP &DUO 6DJDQ DQG have been suggested to be ferric chloride, allotropes
ELRSK\VLFLVW +DUROG 0RURZLW] DQG LQ 6HSWHPEHU WKLV of sulphur, disulphur dioxide and so on, but none of
year, the debate was reawakened with the detection these, so far, are able to satisfactorily explain their
of phosphine there – on Earth, a known indicator of formation and absorption properties,” explained Lee.
biological agencies.
MARK GARLICK X 2, INSTITUTE OF SPACE AND ASTRONAUTICAL SCIENCE/JAPAN AEROSPACE
EXPLORATION AGENCY, ESO/M. KORNMESSER/L. CALÇADA & NASA/JPL/CALTECH, LIFE CYCLE &HUWDLQO\ ELOOLRQV RI \HDUV DJR 9HQXV (DUWK DQG
ILLUSTRATRION: © SARA SEAGER ET AL/2020/ WWW.LIEBERTPUB.COM 0DUV ZHUH PXFK PRUH DOLNH WKDQ WKH\ DUH QRZ
they formed at a similar distance from the Sun
and from the same rocks and metals. If life took
root here, it might well have done so on our sister
worlds, and could have persisted until global climate
catastrophes and other factors turned Mars into a
IUHH]LQJ GHVHUW DQG 9HQXV LQWR DQ LQIHUQR

Cloudy, with a chance of life

The existence of life on Mars now, though, is
contested (see boxout, page 32), and on Venus
Ś JLYHQ LWV HQYLURQPHQW Ś VHHPV DW ƅUVW H[FHHGLQJO\
unlikely. But there is a caveat: Venus is only a
heat trap on its surface. At an altitude of 50km,
the atmospheric pressure drops to 1 bar and the
temperature is comparable to a temperate day on
(DUWK 7KLV LV 9HQXVŝV RZQ KDELWDEOH ]RQH DQG LW UDLVHV
WKH TXHVWLRQ FRXOG OLIH ƆRXULVK DPRQJ LWV FORXGV"

Venus is an extremely cloudy world. Only 20 per
cent of incident sunlight percolates down to the

30 BBC Sky at Night Magazine November 2020

Lifecycle in the clouds on Venus

Astrobiologists have suggested a way that life could exist in
the clouds above Venus in a cycle between atmospheric layers

Altitude (km) Temperature (ºC)
100
a chapter to the subject in his 1998
book Venus Revealed.

New momentum

80 Lower haze In September this year, the debate
40 gathered new momentum with the
20
Upper cloud discovery of the spectral signature
4 of phosphine in Venus’s atmosphere.

3 Temperate Middle and lower cloud, where Phosphine (PH3) is a molecule
2 zone phosphine has been observed consisting of a single phosphorous

atom bonded to three hydrogen

Lower haze atoms. Phosphine is also present on
the gas giants, which are rich in the

hydrogen needed to make it, and on

Earth. On our home world, however,

with negligible free hydrogen in

5 the atmosphere, virtually all of the

Surface haze phosphine is produced entirely by

biological activities.

Like methane, its detection is a

1. Organisms dry out and hibernate in haze layer possible indicator of life, and some
2. Updrafts carry organisms upwards to cloud layer astronomers have proposed looking

3. Organisms enter liquid droplets and rehydrate for it in the spectra of exoplanets’
1 4. Organisms reproduce
atmospheres as they transit their

5. Droplets grow, then sink out of cloud layer parent stars. It isn’t absolutely

certain that the phosphine on Venus

What we do know, at least, is that these unknown is biologically created, but scientists have yet to

PDWHULDOV DUH FRPSDUDEOH LQ VL]H WR OLJKW DEVRUELQJ identify other chemical processes that can make

bacteria back on Earth, and exhibit a similar it there. And this is why its potential existence is so

DEVRUSWLRQ SURƅOH 7KLV LV ZKDW OHG 6DJDQ DQG exciting. Phosphine, and the unknown substance

0RURZLW] LQ WKH V WR VSHFXODWH WKDW WKHVH GDUN absorbing ultraviolet light, taken together make a

patches might be due to the presence of microbes good case for studying the subject more closely.

ƆRDWLQJ LQ WKH FORXGV 2WKHU DXWKRUV KDYH WDNHQ On Earth, microbial life is everywhere. It thrives

a similar stance, notably David Grinspoon of the DURXQG VHD ƆRRU YROFDQLF YHQWV LQ KRW VSULQJV LQ

3ODQHWDU\ 6FLHQFH ,QVWLWXWH LQ $UL]RQD ZKR GHGLFDWHG deserts, in ice and in the sky. Surface bacteria can >

> Sign of life:

the phosphine
molecule is
made up of one
phosphorus
atom and three
hydrodgen atoms

ILLUSTRATION

November 2020 BBC Sky at Night Magazine 31

> EH VZHSW LQWR WKH DWPRVSKHUH ƅQG WKHLU ZD\ LQWR Above the clouds: should our ILLUSTRATION
GURSOHWV RI ZDWHU DQG VXUYLYH DW DOWLWXGHV DV KLJK search for life on other worlds
DV NP /LIH LV LW ZRXOG VHHP XQGRXEWHGO\ YHU\ include the Venusian atmosphere? Dr Mark A Garlick is
KDUG\ 7KH KXPEOH WDUGLJUDGH RU ZDWHU EHDU FDQ a former professional
HYHQ VXUYLYH DIWHU H[SRVXUH WR WKH YDFXXP RI VSDFH (YHQWXDOO\ WKHVH VSRUHV ZRXOG EH NLFNHG EDFN XS astronomer, now
VHHPLQJO\ XQDIIHFWHG E\ FRVPLF UDGLDWLRQ DQG LQWR WKH WHPSHUDWH ]RQH E\ ZLQGV WR EH UHK\GUDWHG a freelance writer,
PLFURJUDYLW\ RU LQGHHG WKH ODFN RI DLU :H NQRZ WKDW HQGLQJ WKHLU VXVSHQGHG DQLPDWLRQ DQG UHVWDUWLQJ illustrator and
VRPH EDFWHULD EDVN LQ DFLGLF FRQGLWLRQV IHHGLQJ RII WKH F\FOH animator specialising
FDUERQ GLR[LGH WR SURGXFH VXOSKXULF DFLG Ś ERWK RI in space
ZKLFK DUH LQ DEXQGDQFH LQ WKH DWPRVSKHUH RI 9HQXV Looking for life

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KDELWDEOH ]RQH DW DURXQG DQ DOWLWXGH RI NP RI OLIH LQ WKH FORXGV 3HUKDSV RXU VHDUFK IRU
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A habitable abode Is there life below the surface? The water
plumes on Saturn’s moon Enceladus come

from a vast ocean below its icy crust

BJDLZX/ISTOCK/GETTY IMAGES, 3000AD/ISTOCK/GETTY IMAGES, Elsewhere in the Solar System there are several ILLUSTRATION
MARK GARLICK/SCIENCE PHOTO LIBRARY/ALAMY environments that might support life

Mars, of course, has long been a favourite among astronomers
for life elsewhere around the Sun. In 1976, the Viking missions
scratched the Martian soil and tested for products that had been
created through biological metabolism. For a while, things
looked promising, but the Vikings’ other experiments detected
no supporting evidence – no signs of the organic molecules
needed to sustain life. Mars came under the spotlight again in
1996 with the discovery of what looked like fossilised bacteria
in a meteorite known to have come from Mars. In the interim,
most scientists have concluded that both reports remain
inconclusive at best.

More recently, speculation has turned to the ice moons of
the gas giants – especially Enceladus, Titan and Europa. Titan,
Saturn’s largest moon, is extremely cold but it has a thick
nitrogen atmosphere and, some say, conditions there mirror what
they were on Earth when life first took hold. Enceladus, also in
Saturn’s system, and Europa, orbiting Jupiter, are both known
to have icy crusts floating on relatively warm, briny seas.

Could these be teeming with life? The only way to know is to
sample these primitive seas – perhaps a submarine on Europa, or
a flight through the plumes of Enceladus to sample the water jets
spewed from beneath the ice and analyse the material.

32 BBC Sky at Night Magazine November 2020



Thank you, Sylvia

Sylvia left a gift in her Will to help conquer Stroke

The first we knew of Sylvia was when for medicine. Becoming a medical Sylvia’s gift has helped fund our work
we received notification of the gift secretary was her next step and, in the to conquer stroke. She’s supported
she’d left us in her Will. Shortly after, course of her career, she discovered research to prevent and treat stroke,
a beautiful story of a much-loved the devastating impact a stroke could and she’s helped care for survivors.
woman began to unfurl. have on people and their families. She And that’s something you can do too –
saw that research and treatment were in the same way.
Friends remembered Sylvia’s kind- vastly under-funded, and she decided
heart and her wish to help others. She to remember the Stroke Association If you would like to learn more about
spent part of her adult-life caring for in her Will. remembering the Stroke Association
her mother, and developed a passion in your Will, please get in touch.

Call 020 75661505 email [email protected]
or visit stroke.org.uk/legacy

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6& $OVR UHJLVWHUHG LQ 1RUWKHUQ ,UHODQG ;7 ,VOH RI 0DQ 1R DQG -HUVH\ 132 6WURNH $VVRFLDWLRQ ,V D &RPSDQ\ /LPLWHG E\ *XDUDQWHH ,Q
(QJODQG DQG :DOHV 1R

Celestial treasure: views of the
Double Cluster in Perseus can
be enjoyed with the naked eye,
binoculars or a telescope

HANNES BACHLEITNER/CCDGUIDE.COM GALACTIC WillGaterexploresthe
science and splendour
of some of the most
striking star clusters in
November’s night sky

GATHERINGS
W hen it comes the cluster-rich regions of the summer eight clusters that we think really
to star clusters, sky are low in the southwest as darkness highlight the spectacular selection that’s
there are few falls, while a quick scan with binoculars on offer, and as we go we’ll also look at
months that can take you on a mesmerising journey the astrophysics that underpins their
offer such a wide through droves of sparkling stellar groups existence. With the Moon out of the way
range of targets scattered among Cygnus, Cassiopeia and from around 6 November, you can start
as November. At the start of the month, Perseus. Here we’ve gathered together seeking them out straight away! >

November 2020 BBC Sky at Night Magazine 35

h AQUILA

12 NGC 6704 Trumpler 35
`
d
Basel 1
M11

M26 lies in a star-rich NGC 6712 NGC 6683
region of the constellation
¡ NGC 6664
Scutum Trumpler 34
M26 b
Messier 26 _

Look to the southwest at the end of SCUTUM
astronomical twilight (around 18:30 UT),
and if your skies are dark and transparent
you may be able to make out a bright
patch hovering over the horizon; this is
the Scutum Star Cloud, a particularly
star-rich swathe of the Milky Way in the
constellation of Scutum. There are several
beautiful star clusters in and around the
Scutum Star Cloud, but the one we’re
looking for is M26. Binoculars should reveal

The birth of an NGC 6649 c
open star cluster
Þ Stop off at M11, the Wild Duck Cluster, on the way from M26 to NGC 6704 at the top of Scutum
Stars aren’t typically born
in isolation, but together in it against the sparkling background stars, the fourth magnitude star Beta (`) Scuti in
huge stellar nurseries but a medium to large aperture telescope \RXU ƅQGHUVFRSH DQG WKHQ PRYH DERXW RQH
LV SUHIHUDEOH XVLQJ WKH ODWWHU \RX FDQ ƅQG LW degree east and half a degree south. The
At this point in our tour we’re by ‘star-hopping’ just under three degrees cluster should then be in the eyepiece or at
exploring a region that sits roughly in east (and a little south) from the third least close by. >
the direction of the Milky Way’s centre. magnitude star Alpha (_) Scuti, via the
You don’t have to look far in this part fainter star Delta (b) Scuti. For the best views of NGC 6704
of the night sky to see signs of the use a large aperture telescope
early stages in a star cluster’s life. NGC 6704
CHART BY PETE LAWRENCE, WILL GATER X 3, MICHAEL BREITE/ STEFAN HEUTZ/
WOLFGANG RIES/CCDGUIDE.COM, RICK JOHNSON/MANTRAPSKIES.COM The most obvious are the immense, We’re not going far for our next object.
dark nebulae that weave across this In fact NGC 6704 is just over four degrees
region. It’s within cold, dusty clouds away, towards the ‘top’ of Scutum. To get
like these that clumps of gas can form; there we’ll cross the brightest patch of
if these grow sufficiently massive, WKH PDJQLƅFHQW 6FXWXP 6WDU &ORXG
nuclear reactions can fire up in their if you’re using a Go-To telescope it’ll take
hearts and they’ll start to shine as mere seconds for the mount to slew to
newborn stars. the cluster, but if you’re doing things
manually this is a great opportunity to
A good example of this process lies take a leisurely wander through the rich
just below the stars of Scutum in the VWDU ƅHOGV DQG SHUKDSV VWRS E\ WKH
Eagle Nebula, M16. This is one of the Wild Duck Cluster, M11. NGC 6704 is
most striking star forming regions in another cluster that is best seen in a
the sky, though it’s best viewed in ODUJH DSHUWXUH WHOHVFRSH 7R ƅQG LW SODFH
summer. Amid the swirling clouds of
this nebula, many stars have formed
close together and a young open
cluster is emerging.

36 BBC Sky at Night Magazine November 2020

The open cluster M39 in
the constellation of Cygnus
is a wonderful imaging target

Imaging highlight: Capture the star cluster M39

The clusters of autumn are great for astrophotographers who are just
starting to capture the night sky and looking for a challenge

Star clusters make great training Before After
targets if you’re new to deep-sky
imaging, and November certainly
isn’t short of bright ones to choose
from. Messier 39 in Cygnus is a perfect
example. It’s home to a decent number
of reasonably bright stars, sits high
above the horizon in the early evening
this month and is large enough on the
sky that it looks impressive in images
captured with introductory level
deep-sky imaging equipment.

Equipment Þ Natural look: bluish star haloes can be toned down with an image-processing program

The cluster spans about 40-arcminutes, for the task of getting things in focus, software. The free DeepSkyStacker is
and it will look nicely placed against the which you’ll need to tackle once you’ve got still the go-to program for beginners.
background stars in the field of view of the cluster stars in your camera’s sights.
a DSLR attached to scopes with focal Tweaks and adjustments
lengths as short as around 400mm. Taking your frames
Then you just need a motorised mount When making the usual contrast, colour
to track the sky during long exposures. When you’re shooting the frames to make balance and ‘curves’ tweaks to your final
It’s worth investing in a Bahtinov mask your final picture, take at least 15-20 image, you may notice that brighter stars
minutes’ worth of exposures. Depending have purple, cyan or blue haloes around
Use a motorised on your local light pollution levels, this them. These can appear for a variety of
mount to keep could mean individual sub-exposures (or reasons, but a way to get rid of them is
your kit tracking subs) of as little as a few tens of seconds to use the ‘Replace Colour’ tool in an
the stars in length up to a minute or so, or more. image-processing program like
Photoshop or GIMP.
Stacking your frames
Set the tool’s ‘fuzziness’ to near its
When sorting your subs, discard any that maximum, then click on a point about
show tracking imperfections or the halfway into the halo’s radius. Lower the
effects of wind gusts, where the stars ‘Saturation’ slider within the tool and the
appear slightly blurred or misshapen. tint of the haloes should disappear,
Then process the images in stacking making the picture look more natural.

November 2020 BBC Sky at Night Magazine 37

` f
NGC 7243
_ CYGNUS NGC 6826
e
Mini-W

IC 5146 M39 k

NGC 7209 NGC 7082 Deneb k NGC 6811 LYRA
b
_
NGC 7000 Vega e
LACERTA j IC 5070 k
¡_
NGC 7027 NGC 6819 g
dc
i Sadr Collinder 419 b Stephenson 1

a e

m Northern M29 ` Sheliak
Cross NGC 6888
o
NGC 7063 IC 4996 NGC 6871

i Biurakan 2 Sulafat M57
/
d a

Gienah

¡

M56

c q HERCULES

Veil Nebula Albireo `
Complex
NGC 6940
_ VULPECULA
fg
NGC 6823

M27
Collinder 399

PEGASUS a _ ¡
M71 b `
From The Coathangeer in Vulpecula, follow the c AQUILA
dark dust lane northeast to NGC 6940, before a_ SAGITTA
heading into Lacerta to locate NGC 7209 c NGC 6709

b`

The Coathanger You’ll get a good view
of NGC 6940 through
From Scutum we’re now going to traverse a larger telescope
the stars of Aquila and Sagitta to focus on
CHART BY PETE LAWRENCE, BERNHARD HUBL/CCDGUIDE.COM X 2, a wonderful sight in the realm of Vulpecula,
HANNES BACHLEITNER/CCDGUIDE.COM, the Fox. The Coathanger – also known
as Collinder 399 or Brocchi’s Cluster – sits
about four and half degrees to the south
of the star Anser (Alpha (_) Vulpeculae).

It’s a great target for a pair of binoculars,
as the cluster appears about one and a
half degrees across on the sky and contains
PRVWO\ ƅIWK DQG VL[WK PDJQLWXGH VWDUV

There are several ways you can go about
tracking it down, but probably the easiest
is to slowly scan the region between the
bright stars Albireo (Beta (`) Cygni) in
Cygnus, and Altair (Alpha (_) Aquilae) in
Aquila. From a dark-sky location it is a
ƅQH VLJKW VLWXDWHG DPRQJ WKH JUDQXODU
VWDU ƅHOGV DQG GDUN JDODFWLF GXVW ODQHV

NGC 6940 dark path to NGC 6940 is easily visible WKH WDUJHW E\ ƅUVW VHOHFWLQJ D ORZ SRZHU
to the naked eye under dark skies, you’ll H\HSLHFH Ś DURXQG [ PDJQLƅFDWLRQ LV
The Coathanger sits within a prominent need a larger scope to see the cluster ideal. Next, place the fourth magnitude
dust lane – known as the Great Rift – that ZHOO ,I \RXŝUH XVLQJ D PDQXDO PRXQW ƅQG star 41 Cygni on, or near to, the westernmost
runs all the way from the Galactic Core
region through the constellation of Cygnus
DQG EH\RQG 7R ƅQG RXU QH[W FOXVWHU ZH
need to follow this celestial silhouette to
the northeast, in the direction of the third
magnitude star Zeta (c) Cygni. While this

38 BBC Sky at Night Magazine November 2020

The Coathanger makes
an ideal target for a
pair of binoculars

HGJH RI WKH ƅHOG RI YLHZ 7KHQ PRYH VRXWK GXULQJ WKH ƅUVW KDOI RI 1RYHPEHU DIWHU Scattered
by about two degrees to see NGC 6940. which the Moon starts to interfere. NGC among a spiral
7209 lies close to the diamond-shape of
NGC 7209 stars that make the head of Lacerta. The cloudy band of the
Milky Way is home to many
Our next object takes us northeast from 7R ƅQG LW LQ D PHGLXP DSHUWXUH VFRSH wonderful star clusters
Cygnus over into Lacerta, and as we’re place the mag. +4 star 5 Lacertae on the
moving further east in the sky, the objects QRUWKHUQ HGJH RI WKH ƅHOG RI YLHZ WKURXJK You may have noticed that as we’ve
we look at now will be well-placed for more a low-power eyepiece (ideally around 20x been moving to objects a little higher
of the night than some of our earlier targets. PDJQLƅFDWLRQ 7KHQ PRYH WKH VFRSH in the sky, we’ve been weaving in and
a little over four degrees to the west out of the bright band of the Milky
Our current target, NGC 7209, will sit and you should be able to pick out the Way. In fact, most of the clusters in
nice and high right up until the small hours cluster’s stars. > this guide appear close to it on the sky.

NGC 7209 is particularly Why might this be? The answer is
well-placed for observing that when we’re looking into the
GXULQJ WKH ƅUVW KDOI RI 1RYHPEHU misty light of the Milky Way we’re
gazing into the disc of our Galaxy.
This disc is composed of structures
known as spiral arms and it’s in these
glittering streams of stars that we find
the star factories of the Milky Way.

As we’ve already seen, it’s in these
star-forming nebulae that open star
clusters begin their lives, so it follows
that many of the young star clusters
we see today sit close to the spiral
arms that make up the band of the
Milky Way.

November 2020 BBC Sky at Night Magazine 39

CAMELOPARDALIS

` IC 342 CASSIOPEIA
NGC 1502
Tombaugh 5 f

NGC 637

Trumpler 3 Segin Trumpler 1
b
¡
NGC 654 M103
NGC 436
IC 1805 NGC 663
NGC 659 NGC 457

Stock 2

IC 1848

NGC 957 h Wanderers
within the Galaxy
Trumpler 2 r Double Cluster
d Clusters don’t stay together
NGC 744 forever, and soon the
family drifts apart
a M76
q As an open star cluster grows older it’s
NGC 1444 thought that gravitational interactions
ANDROMEDA cause the stars in the grouping to drift
NGC 1528 Melotte 20 f o apart, scattering throughout space.
h e
Mirfak This likely happened with the Sun
NGC 1513 long ago. Indeed, astronomers today
+ _ are studying the chemical
composition of nearby stars to
sm pinpoint potential members of our
b NGC 1245 star’s maternal cluster.

g NGC 956 Understanding the motions of the
a stars, and star clusters, in the night
M34 sky can shed light on their history.
i Almach One mission that is proving to be a
powerful tool in this respect is the
Algol ` NGC 891 European Gaia satellite.

¡ / NGC 1023 NGC 752 From orbit it has been charting the
positions and velocities of millions of
PERSEUS t TRIANGULUM stars in our Galaxy, giving researchers
a view of how the stellar inhabitants
l ` of the Milky Way are moving on
b astronomical timescales, and the
NGC 1499 NGC 1342 a relationships between them.

j

NGC 1245 can be located
in Perseus near Mirfak,
below the Double Cluster

NGC 1245 You’ll be able to enjoy views of NGC 1245
with a medium aperture telescope
> We’re now going to make a huge jump
CHART BY PETE LAWRENCE, GÜNTER KERSCHHUBER/CCDGUIDE.COM, WILL GATER X 2 – across some 50 degrees of sky – through
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here we’re going to examine an open
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40 BBC Sky at Night Magazine November 2020

The Double Cluster and Double Cluster
open cluster NGC 1245
are highlights in Perseus, a
cluster-rich part of the sky

NGC 1245

“Good binoculars The Ursa Major Moving Group WKH QDNHG H\H VWDUV 0HUDN %HWD `
will bring many of includes some of the stars in the $OLRWK (SVLORQ ¡ DQG 0HJUH] 'HOWD
the brighter stars of familiar asterism known as The Plough b 8UVDH 0DMRULV DUH DFWXDOO\ SDUW RI D
the clusters into FROOHFWLRQ NQRZQ WR DVWURQRPHUV DV WKH
view; in fact there’s an ZLWK D WHOHVFRSH FHUWDLQO\ WU\ D ORZ SRZHU 8UVD 0DMRU 0RYLQJ *URXS 6RPH VFLHQWLVWV
argument to be made H\HSLHFH ƅUVW Ś WR JHW WKDW ZRQGHUIXO EHOLHYH WKHVH VWDUV IRUPHG WRJHWKHU DV
that this is the best ŜƆRDWLQJ LQ VSDFHŝ IHHO Ś EHIRUH \RX GLYH LQ D FOXVWHU EXW DUH QRZ GLVEDQGLQJ DV WKH\
way to enjoy the IRU D KLJKHU PDJQLƅFDWLRQ ORRN PRYH WKURXJK WKH 0LON\ :D\
Double Cluster”
Stars in Ursa Major Will Gater is an
The Double Cluster astronomy journalist
2XU ODVW VWDU FOXVWHU LV VRPHWKLQJ D ELW and science presenter.
,I \RXU VNLHV DUH GDUN \RX PD\ EH DEOH GLIIHUHQW WR WKH RWKHUV LQ RXU JXLGH <RX His latest book,
WR SLFN RXW D OLWWOH IX]]\ JUH\ LVK SDWFK ZRQŝW QHHG D VFRSH RU D SDLU RI ELQRFXODUV The Mysteries of the
EHWZHHQ WKH VWDUV RI &DVVLRSHLD DQG <RXŝOO EH DEOH WR XVH MXVW \RXU H\HV WR Universe, has just
3HUVHXV XVLQJ MXVW \RXU H\HV 7KHVH DUH WKH VHH VRPH RI LWV PHPEHUV Ś WKRXJK WKLV been published by DK
RSHQ FOXVWHUV 1*& DQG 1*& ZKLFK FOXVWHU SUREDEO\ ZRQŝW ORRN OLNH ZKDW \RXŝUH
WRJHWKHU PDNH WKH IDPRXV 'RXEOH &OXVWHU LPDJLQJ 7R VHH LW MXVW ORRN QRUWK WRZDUGV
WKH SHQXOWLPDWH REMHFW LQ RXU WRXU 8UVD 0DMRU 7KDWŝV EHFDXVH D QXPEHU RI
WKH VWDUV LQ WKLV SDUW RI WKH VN\ Ś LQFOXGLQJ
*RRG ELQRFXODUV ZLOO EULQJ PDQ\ RI WKH
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ZKHUH WKH 0LON\ :D\ UXQV WKURXJK WKLV SDUW
RI WKH VN\ ,I \RXŝUH REVHUYLQJ WKH FOXVWHUV

November 2020 BBC Sky at Night Magazine 41

DISCOVER
MORE

ABOUT SATURN’S
LARGEST MOON

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International Space Station
Architecture beyond Earth
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16-PAGE
CENTRE
PULLOUT

The Sky Guide

NOVEMBER 2020

LUNAR

HIDE AND SEEK

Observe the waning gibbous
Moon as it occults the southern
region of the open cluster M35

TWIN PEAKS

Get the best views of
the Northern Taurid and
Leonid meteor showers

PETE LAWRENCE DISTANT PURSUIT

How to spot the planet Uranus

with the naked eye

About the writers Also on view Red light friendly Get the Sky
this month… Guide weekly
Astronomy Steve To preserve your night
expert Pete Tonkin is ✦ Asteroid 8 Flora vision, this Sky Guide For weekly updates on
Lawrence is a binocular reaches opposition can be read using a red what to look out for in
a skilled astro observer. light under dark skies the night sky and more,
imager and Find his tour ✦ Get to know the Moon’s sign up to our newsletter
a presenter on The Sky at of the best sights for clair-obscur effects at www.skyat
Night monthly on BBC Four both eyes on page 54 nightmagazine.com
✦ The Pleaides reaches
its highest point in the sky

November 2020 BBC Sky at Night Magazine 43

NOVEMBER HIGHLIGHTS Yourguidetothe
night sky this month

Sunday Tuesday

1 Catch a view of mag. –3.9 3 Jupiter and
Venus this morning around Saturn now
05:00 UT and look hard just to
the south of the planet (below appear less than
and right as seen from the UK) to see
mag. +3.9 star Zavijava (Eta (¡) Virginis), Ō DSDUW LQ WKH
currently sitting 15.6 arcminutes from
the planet. early evening sky.

Minor planet 8 Flora reaches opposition
in Cetus at mag. +8.0.

Monday

9 This morning
presents an
opportunity to spot
the rare clair-obscur
effect known as the Curtiss
Cross. The cross is formed
from relief features near to the
6km-crater Frau Mauro H.

Friday Saturday X

13 Catch mag. –3.9 Venus near 14 With the Moon
a slender 5%-lit waning out of the way
crescent Moon this morning. Both this is a great time
objects will be well presented from to try our ‘Deep
around 05:00 UT onwards, low in the Sky Tour’ on page 56, which
east-southeast. Mag. –0.6 Mercury joins looks at objects around the
the party later, rising around 05:30 UT. foot of Perseus, the Greek Hero.

Tuesday Wednesday

17 The annual 18 Look towards
Leonid meteor the southwest
shower reaches its as the sky darkens
peak this evening. As to see mag. +0.9
the Moon is just two days old, Saturn, mag. –1.9 Jupiter and
the conditions for viewing a 16%-lit waxing crescent
these swift meteors are good. Moon close together. Saturn
and Jupiter are separated
E\ MXVW Ō WKH 0RRQ
EHLQJ Ō ZHVW RI Jupiter.

PETE LAWRENCE X 8 Family stargazing Sunday X

The Andromeda Galaxy, M31, is a distant galaxy which 22 The lunar X and
can be seen with the naked eye. First, identify the Great V clair-obscur
Square of Pegasus using our main chart on page 50. effects are visible in
Next, extend the top edge of the square left by the same length, daylight hours,
bending up slightly to locate a star that’s a similar brightness to reaching a peak after 14:00 UT.
the square’s stars. Then turn 90Ō, heading up the sky to a dimmer
star. Keep going for an even dimmer star and M31 lies next to this, Later, in darkness, use a
appearing like an elongated fuzzy patch. If your young observers high magnification on
can spot it, tell them that the light they are seeing left M31 2.5 crater Albategnius to see the
million years ago! www.bbc.co.uk/cbeebies/shows/stargazing clair-obscur effect known
as the Face in Albategnius.

44 BBC Sky at Night Magazine November 2020

M35 NEED TO

Thursday X KNOW

5 Starting just The terms and symbols
after 01:00 UT, used in The Sky Guide
the 82%-lit waning
gibbous Moon will Universal time (UT)
begin to move in front of and British Summer
the southern part of the Time (BST)
open cluster M35 in Gemini.
Universal Time (UT) is
Tuesday Wednesday Thursday the standard time used
by astronomers around
10 Mercury 11 Despite being 12 Today is the peak the world. British
reaches dim at mag. +14.1, of the Northern Summer Time (BST) is
greatest western the dwarf planet Taurid meteor shower; one hour ahead of UT
HORQJDWLRQ Ō Pluto is conveniently its ZHR (zenithal hourly
from the Sun. The mag. –0.4 positioned near the gas rate) is low at 5 meteors per hour, RA (Right ascension)
planet is visible in the morning giant Jupiter. This evening, but it does have a broad peak. and dec. (declination)
sky, rising two hours before both planets are just
the Sun and visible above 42 arcminutes apart. Mag. –3.9 Venus sits 1.3 These coordinates are the
the east-southeast horizon. arcminutes from mag. +4.4 night sky’s equivalent of
Theta (e) Virginis at 05:50 UT. longitude and latitude,
describing where an object
Sunday W Monday is on the celestial ‘globe’

15 The weak 16 Mag. –1.6 Mars Family friendly
Iota Aurigid reaches a stationary
meteor shower point today, as its Objects marked
reaches a peak previous western with this icon are perfect
with a ZHR (zenithal hourly motion against the for showing to children
rate) of 8.2 meteors per background stars comes to a
hour. A new Moon provides halt. After today, the planet’s Naked eye
a great opportunity to view motion resumes, this time east
this less familiar shower. against the background sky. Allow 20 minutes
for your eyes to become
Thursday Friday X dark-adapted

19 This evening, 20 The beautiful Photo opp
the 25%-lit Pleiades open
waxing crescent cluster reaches its Use a CCD, planetary
Moon is arranged highest position in camera or standard DSLR
with Saturn and Jupiter to the sky, due south at midnight.
form a right-angled triangle, Its a superb object to explore Binoculars
with Saturn at the right angle. with binoculars – a reclining
garden chair will give you the 10x50 recommended
most comfortable experience.
Small/
medium scope

Reflector/SCT under 6 inches,
refractor under 4 inches

Large scope

Reflector/SCT over 6
inches, refractor over 4 inches

Thursday X Monday GETTING STARTED

26 Mag. –1.3 30 Today’s full Moon IN ASTRONOMY
Mars and occurs close to
an 83%-lit waxing the furthest point in If you’re new to
gibbous Moon its orbit from Earth, astronomy, you’ll find
sit 4.9Ō from one another known as apogee (27 November). two essential reads on our
in the early hours. As a result, the full Moon will website. Visit http://bit.
appear smaller and dimmer than ly/10_easylessons for our
average – the effect is known 10-step guide to getting
as a ‘micromoon’! started and http://bit.ly/
buy_scope for advice on
choosing a scope

November 2020 BBC Sky at Night Magazine 45

THE BIG THREE The three top sights to observe or image this month

CASSINI’S MOON MAIDEN FACE IN ALBATEGNIUS < Tricks of the light: look out for this

Ō: Ō1 FR ORQJLWXGH Ō Ō( Ō6 FR ORQJLWXGH Ō month’s clair-obscur effects, caused
A long-haired seated girl formed Profile of a face created by by sunlight on the Moon’s surface
by Promontorium Heraclides. the shadow of the eastern
%HVW WLPH WR VHH Morning framing for reappearances only, positioning
terminator, four days after rim of crater Albategnius. your telescope so only the dark, night-side
first quarter. Best seen with an %HVW WLPH WR VHH Morning SRUWLRQ RI WKH 0RRQ LV LQ WKH ƅHOG RI YLHZ
inverted (south-up) view.
terminator, last quarter. A number of interesting clair-obscur
events also take place this month, some of
CURTISS LUNAR 2 which are less common than the usual fare.
CROSS In the early hours of 8 November, it should
Ō: Ō6 FR ORQJLWXGH Ō be possible to see the Lunar 2 – a thin,
Ō: Ō6 Thin, bright numeral ‘2’ formed casually written ‘2’ formed by sunlight on
FR ORQJLWXGH from the rims of craters Deluc the rims of craters Deluc and Deluc D
Ō – at 02:45 UT (co-longitude 182.0Ō).
Challenging (48km) and Deluc D (27km).
cruciform lighting %HVW WLPH WR VHH Evening Then on the night of 8/9 November,
effect near crater terminator, last quarter. WZR FURVVHV VKRXOG EH YLVLEOH 7KH ƅUVW LV
Fra Mauro H. known as the Tycho Cross and is formed by
%HVW WLPH WR features in the vicinity of the western ring
VHH Evening of Tycho, near moonrise at 22:45 UT
terminator, (co-longitude 192.2Ō). Later, the Curtiss
waning crescent. Cross forms as the Sun sets over the
Fra Mauro Zeta ridge complex, 90km
TYCHO CROSS northeast of Fra Mauro’s centre at 01:00 UT
(co-longitude 193.3Ō). On the 22nd, just
Ō: Ō6 FR ORQJLWXGH Ō after 22:00 UT (co-longitude 2Ō), look
Cruciform clair-obscur effect which includes features for the Face in Abategnius: use a high
near the western rim of ray crater Tycho. PDJQLƅFDWLRQ RQ FUDWHU $OEDWHJQLXV ZKHUH
%HVW WLPH WR VHH Evening terminator, waning crescent. you should be able to see the shadow of
WKH FUDWHUŝV HDVWHUQ ULP RQ LWV ƆRRU 6HH LI
DON’T MISS the cluster’s outer stars from 01:20 UT. \RX FDQ PDNH RXW WKH SURƅOH RI D IDFH WKHUH
From around 01:50 UT it should be possible
NOVEMBER to see stars reappearing from behind the Finally, an easy clair-obscur is visible on
Moon’s dark limb, with the occultation 26 November. Look at the Bay of Rainbows
HQGLQJ DURXQG 87 ,I \RX ƅQG \RXUVHOI or Sinus Iridum, located on the northwest
struggling with the brightness of the shore of Mare Imbrium. The southern end
illuminated portion of the Moon, try of the Jura mountains peters out here in
the Promontorium Heraclides. At 20:40 UT
(co-longitude 50.0Ō) an inverted scope view
RI WKLV IHDWXUH VKRXOG UHYHDO WKH SURƅOH RI
a girl with billowing hair; this is Cassini’s
Moon Maiden.

MOON EVENTS A photographic simulation of the Moon
passing across the southern part of
BEST TIME TO SEE: open cluster M35 on 5 November
As stated, 5 November 01:20–03:00 UT
for the M35 occultation

ALL PICTURES: PETE LAWRENCE The Moon puts on a good show this
month. Beginning on the morning of
5 November, an 82%-lit waning gibbous
Moon passes in front of the southern part
of the rich open cluster M35, in Gemini.
Although the bright Moon will drown out
the fainter stars, a scope trained on the
Moon’s northern limb should show the
brighter cluster members. The Moon’s
bright limb leads the occultation, hiding

46 BBC Sky at Night Magazine November 2020

Leonid meteor shower 2020 þ The radiant of the

BEST TIME TO SEE: In the morning, 17 and 18 November Leonids is located in Leo,
in the Sickle asterism

The annual Leonid meteor shower &$1&(5 M44
reaches its peak activity at 11:00 UT
on 17 November with a ZHR (zenithal /(2 0,125
hourly rate) estimated to be somewhere in
the range of 10–20 meteors per hour. This Sickle 1RY
peak time is obviously in daylight, but
there are also some interesting predictions URSA 1RY Leonid peak
for dust trail crossings at periods that will MAJOR
be in darkness for UK viewing. 1RY
Generally, the Leonids are best observed Denebola
after midnight and technically they should Algieba
be putting on their best show during the `
morning of 17 November from 00:00 UT VIRGO a
until the onset of dawn, around 05:40 UT.
A watch on the morning of 18 November 1RY
should still produce results, but is further
from the predicted ZHR peak of 11:00 UT Regulus HYDRA
than the morning session on the 17th.
An added bonus is that this year’s new _
Moon is out of the way for the peak period.
Although there’s a prediction of LEO
enhanced activity from 06:50 UT until Moon phase
08:13 UT on the morning of 17 November,
it’s expected that this will consist mostly Alphard
of faint meteor trails. It’s also when the sky
will be bright with morning twilight from the 1RY
UK. A second period of enhancement may
ZD[LQJ FUHVFHQW

Sets at 87
Favourable

occur during darkness in the early morning Leonid meteors can typically be seen
of 18 November at 00:58 UT. However, it’s between 10–20 November; they are fast
not expected that these predictions are meteors, associated with the debris stream
JRLQJ WR SURGXFH VLJQLƅFDQW UDWH LQFUHDVHV of comet 55P/Tempel-Tuttle. The radiant is
as the trails which are responsible for them located within the curved portion of the
will have spread over time and will have Sickle asterism in Leo, the pattern that is
become sparse. meant to represent the Lion’s head.

A favourable Montes Cordillera Look out for features on
southwest libration Lacus Autumni the southwest limb of the

BEST TIME TO SEE: Mornings of 5–12 November. Moon during November

The Moon’s globe over time. Between 5–12 Lacus Veris
appears to face the same November, libration favours Montes Rook
way towards our planet the Moon’s southwestern limb
because it’s gravitationally and here there is a fantastic Mare Orientale
locked to Earth. However, the feature to look out for. Hidden
fact that its orbit around Earth from view most of the time, From Earth, we can only get much harder. The best views will
is elliptical and tilted slightly it’s a 1,000km-diameter a tantalising glimpse of the be during the mornings of 5–12
means it appears to rock and concentric ring basin centred 300km Mare Orientale, November as the Moon moves
roll slightly over time, an effect on Mare Orientale. extremely foreshortened to into its waning phases prior to
known as libration. PDNH IHDWXUH LGHQWLƅFDWLRQ WKDW new Moon on 15 November.
If the Moon faced Earth A spacecraft’s view from
strictly with no variation, we’d directly overhead would reveal
only be able to see 50 per cent an impressive ‘bull’s eye’ impact
of its face, but libration allows basin, the rings of the bull’s eye
us to see a bit extra, in total 59 delineated by mountain ranges.
per cent of the Moon’s surface Interspersed between them
are dark lava lakes.

November 2020 BBC Sky at Night Magazine 47

THE PLANETS Our celestial neighbourhood in November

PICK OF THE ARIES

MONTH _

Hamal Sheraton

Pleiades ` PISCES
¡a

Uranus bd

Best time to see: 1 November, 23:50 UT TAURUS k Uranus 19 ¡
Altitude: Ō h m
Location: Aries 1RY 1RY k
Direction: South i
Features: Small greenish disc, 1RY
brighter moons + j j1
Recommended equipment: j + 1RY Mars
150mm or larger j2 i
k
Uranus was at opposition on 31 October i
and remains well placed for UK viewing Menkar Alrescha _
throughout November and December.
:KLOH RSSRVLWLRQ PDUNV D ELJ FKDQJH _ a
in the appearance of a close planet like
Mars, for the distant ice giants Uranus and b CETUS
Neptune, the difference is small.
Uranus sits about 60 per cent
Easily seen though binoculars, the tricky of the way along a line between
aspect of identifying Uranus currently
comes from its location in southern Aries Menkar and Sheratan
where there aren’t many stars to signpost
it. One way to locate its general area is the planet, and this is the best Although its disc is small,
to identify Menkar (Alpha (_) Ceti) and
Sheratan (Beta (`) Arietis); Uranus lies 60 way to positively identify imaging setups have recorded
per cent of the way along this line, starting
at Menkar. Through binoculars, Uranus it through the eyepiece. URANUS features on the planet in
looks like a mag. +5.7 star, which again Uranus currently presents the past. These normally
isn’t particularly helpful as there are other
stars of similar brightness in the area. a 3.8 arcsecond disc, consist of bands in the

A small telescope is the minimum you which can be seen with a Umbriel planet’s atmosphere
need to bring out the amazing colour of
small scope, while larger Ariel but additionally, ‘hot-

instruments will show Titania spot’ bright regions have
this disc very clearly. An been recorded too: huge

interesting challenge for Oberon storms within the planet’s
large aperture telescope atmosphere. Filters are

PETE LAWRENCE X 3 owners, or those with Þ See if you can image typically used to reveal
planetary imaging setups, detail like this, popular
is to try and record the the brighter moons of choices being IR 685 or
brighter moons of Uranus: Uranus this month 5* ƅOWHUV FRPELQHG

Miranda (mag. +16.5), Ariel (+14.3), Umbriel with a camera that is particularly sensitive

(15.0), Titania (+13.9) and Oberon (+14.1). to red and infrared light.

The planets in November The phase and relative sizes of the planets this month. Each planet is shown
with south at the top, to show its orientation through a telescope

Venus Mars Jupiter Saturn Uranus Neptune
15 Nov 15 Nov 15 Nov 15 Nov 15 Nov 15 Nov

Mercury 0” 10” 20” 30” 40” 50” 60”
1 Nov ARCSECONDS

Mercury
15 Nov

Mercury
30 Nov

48 BBC Sky at Night Magazine November 2020

Mercury changes from westward to JUPITER’S MOONS: NOV
eastward. It remains bright but
Best time to see: 10 November, dimming, with a 20 arcsecond Using a small scope you can spot Jupiter’s biggest moons.
from 06:00 UT disc on the 1st, shrinking to Their positions change dramatically during the month, as shown
Altitude: 3.5Ō (low) 15 arcseconds by the 30th. on the diagram. The line by each date represents 00:00 UT.
Location: Virgo
Direction: East-southeast Jupiter DATE WEST EAST
Mercury is a morning object
all month; on 1 November Best time to see: 1 November, 1
it’s at mag. +1.5 and rises over 17:45 UT 2
the east-southeast horizon Altitude: 14Ō 3
70 minutes before the Sun. It Location: Sagittarius 4
brightens to reach mag. –0.4 Direction: Just west of south 5
on the 10th when it’s at Jupiter is visible all month in 6
greatest western elongation the evening sky, to the west of 7
Ō : ULVLQJ WZR KRXUV EHIRUH south as darkness falls. Shining 8
the Sun. Neptune maintains a around mag. –2.0 it appears 9
good brightness, shining at close to Saturn. Both planets 10
mag. –0.7 on the 30th and start to converge noticeably 11
rising an hour before sunrise. this month, their separation 12
reducing from just over 5Ō at the 13
Venus start to 2.3Ō by the month’s end. 14
15
Best time to see: 1 November, Saturn 16
05:30 UT 17
Altitude: 14Ō Best time to see: 1 November, 18
Location: Virgo 17:45 UT 19
Direction: East-southeast Altitude: 15.5Ō 20
Venus is creeping closer to the Location: Sagittarius 21
Sun in the morning sky. Despite Direction: Just west of south 22
this it remains prominent during Saturn shines just to the east of 23
November. On the 1st, mag. –3.9 Jupiter, currently at mag. +0.9, 24
Venus rises 3.5 hours before with both planets converging 25
the Sun, a telescope revealing towards the month’s end 26
its phase to be 81% with an ahead of December’s Great 27
apparent size of 13 arcseconds. Conjunction. A 25%-lit waxing 28
By the end of the month it rises crescent Moon forms a 29
2 hours and 40 minutes before right-angled triangle with 30
the Sun and shows an 88%-lit Jupiter and Saturn on the 19th. 1
disc, 11 arcseconds across
through a telescope eyepiece. Neptune 8 76 54 3 2 1 01 2 34 5 6 78
On the 13th, it’s grouped with arcminutes
a 5%-lit waning crescent Best time to see: 1 November,
Moon and mag. –0.6 Mercury. 20:50 UT Jupiter Io Europa Ganymede Callisto
Altitude: 31Ō
Mars Location: Aquarius
Direction: South
Best time to see: 1 November, Neptune is well placed in the
22:30 UT evening sky, just to the east
Altitude: 42Ō of Phi (s) Aquarii. It shines at
Location: Pisces mag. +7.8, so you’ll need at least
Direction: South binoculars to see it. It passes
Mars was at opposition on its highest point in the sky, due
13 October and remains bright south, in darkness all month
through November, but dims and appears to nudge west
from mag. –2.1 on the 1st to towards Phi Aquarii.
mag. –1.1 on the 30th. The
planet reaches a stationary More ONLINE
point in the sky on the 16th
when its apparent movement Print out observing forms for
recording planetary events

November 2020 BBC Sky at Night Magazine 49

THE NIGHT SKY – NOVEMBER

Explore the celestial sphere with our Northern Hemisphere all-sky chart NORT

KEY TO When to use this chart HEAST ak
STAR CHARTS
1 November at 00:00 UT
Arcturus STAR NAME 15 November at 23:00 UT
30 November at 22:00 UT
PERSEUS CONSTELLATION LEO MINOR
NAME On other dates, stars will be in slightly different positions
GALAXY because of Earth’s orbital motion. Stars that cross the
sky will set in the west four minutes earlier each night.
OPEN CLUSTER

GLOBULAR How to use this chart _
CLUSTER
1. Hold the chart
PLANETARY so the direction LYNX
NEBULA you’re facing is
at the bottom. M44
DIFFUSE 7th ¡
NEBULOSITY 2. The lower half CANCER
of the chart
DOUBLE STAR shows the sky X Pollux Castor _
VARIABLE STAR ahead of you.
_ `
3. The centre of
THE MOON, the chart is the S
SHOWING PHASE point directly
over your head.

COMET TRACK GEMINI

Sunrise/sunset in November* EAST

ASTEROID Date Sunrise Sunset b
TRACK
1 Nov 2020 07:10 UT 16:37 UT Procyon 6
STAR-HOPPING 11 Nov 2020 07:29 UT 16:19 UT M37
PATH 21 Nov 2020 07:47 UT 16:05 UT
01 Dec 2020 08:03 UT 15:55 UT CANIS _` Elnath
METEOR MINOR
RADIANT a 4th

Moonrise in November* M1

c

Circlet ASTERISM Moonrise times

PLANET 1 Nov 2020, 17:15 UT 17 Nov 2020, 10:35 UT MONOCEROS Betelgeuse Alde
5 Nov 2020, 19:24 UT 21 Nov 2020, 13:40 UT
9 Nov 2020, --:-- UT 25 Nov 2020, 14:41 UT _
13 Nov 2020, 04:36 UT 29 Nov 2020, 15:41 UT ORION

QUASAR *Times correct for the centre of the UK a Bellatrix

STAR BRIGHTNESS: Lunar phases in November ` M78
a
MAG. 0
& BRIGHTER Saturday Sunday Monday Tuesday Wednesday Thursday Friday
1 23456
MAG. +1 Mirror of Venus
7 8 9 10 11 12 13
MAG. +2 i `
`
MAG. +3 M42e

MAG. +4 Rigel
& FAINTER
SOUTHEAS
5º N W COMPASS AND 14 15 16 17 18 19 20 LEPUS
E FIELD OF VIEW _
NEW MOON
CHART: PETE LAWRENCE Ta
21 22 23 24 25 26 27
`

S

MILKY WAY

28 29 30

FULL MOON

50 BBC Sky at Night Magazine November 2020