Earth And
Space
Exploration
Student’s Name : Tan Xin Yi
Class : 2M
Teacher’s Name : Puan Rumaizah
The Formation Of Star
- A star is born from a nebula.
Gases and dust in the nebulae are pulled together by
the strong force of gravity until they form a globe.
The globe of gases will contract and compress due to
strong gravitational forces until they form a denser
core.
The core becomes smaller gradually. A nucleus
reaction takes place when the temperature and
the pressures are too high. Hydrogen gas is
changed to helium.
A lot of heat energy and light energy are released
from the core. The core begins to shine, a new star
is born.
- The star that is born is called a young star or an
infant star.
- This young star will continue to expand into an
average star like the Sun or a massive star.
The Death Of Star
▪ The lifespan of a star depends on its size. A
small-sized star has a longer lifespan
compared to a big-sized star.
▪ A star will die once the hydrogen gas in its
core is used up for its nuclear reaction.
▪ Then, the core would begin to contract and
its outer parts expand to become a red giant.
▪ If the star is an average star, the red giant
star would change into a white dwarf star.
▪ If the star is a large star, a red giant star
would expand to become a supergiant star
and then explode. This explosion is known as
supernova. This explosion produces a lot of
heat and light energy and can be seen during
the day.
▪ This explosion produces a neutron star.
▪ If the original star is a super-large star, a
supernova explosion would produce a hole
known as a black hole.
The Milky Way
▪ The Milky Way is a spiral shaped medium
size galaxy.
▪ It is made up of approximately 200
billions stars.
▪ Our solar system is located at the edge of
one of the spiral arms of the Milky Way.
▪ The centre of the solar system is the Sun.
The distance of the Sun from the centre
of the galaxy is 30 000 light years away.
Mercury Planets In Solar System
Venus
Earth • The closest planet to the sun.
• The smallest planet in the solar system. Mercury’s diameter is
40% smaller than the Earth’s diameter.
• Mercury’s sky always appears dark because it does not have a
layer of atmosphere to scatter the sunlight.
• The absence of atmosphere to burn meteoroids is a factor why
Mercury’s surface has craters and rocks, as a result of being hit
by meteoroids, just as in the Moon.
• The temperature on its surface during the day is very high. It is
approximately 480°C while the temperature at night is
extremely cold, approximately -170°C.
• The second closest planet to the Sun.
• The name Venus is derived from the Roman goddess of love and
beauty.
• Venus has a layer of atmosphere with a high content of carbon
dioxide. Therefore, it is also known as the “greenhouse” planet.
The temperature on its surface is approximately 460°C because
of the high content of carbon dioxide.
• The rotation of this planet is from east to west, unlike the
Earth’s. This means that the Sun rises in the west.
• According to astronomers, Venus is the “Earth’s twin” because
its age, mass and volume is the same as the Earth’s.
• The third planet in the Solar System.
• The fifth largest planet in the Solar System.
• The Earth is one of the planets in the universe inhabited by living
things.
• The Earth is surrounded by a layer of atmosphere made up of
nitrogen gas, oxygen, carbon dioxide, argon and water vapour.
• 71% of the surface of the Earth is covered with water and 29%
is covered with land.
Mars • Fourth planet from the Sun.
Jupiter • Mars is also known as the Red Planet.
Saturn • Mars has two moons, they are Phobos and Demos.
• Its surface is covered with reddish sand dust and
there are craters, volcanoes and frozen water at its
poles.
• It has a thin atmosphere and an extremely high
content of carbon dioxide at 96%.
• Fifth planet from the Sun.
• The largest planet in the Solar System with a
diameter 12 times bigger than the Earth and a
mass 320 times heavier than the mass of the Earth.
• It has 67 moons orbiting it and the largest moon is
Ganymede.
• Jupiter has a gravitational pull force that acts as a
protector to the Earth because it is capable of
deflecting massive objects from hitting Earth.
• Sixth planet from the Sun.
• Second largest planet after Jupiter.
• Saturn is made up of gases and is classified as a gas
giant planet.
• Saturn is one of the planets that has a lesser
density than water (30% less dense).
• 62 moons orbit Saturn, the largest being Titan.
• It has a ring system made up of ice with small
amounts of rocky material and dust.
Uranus • Seventh planet from the Sun and is the third
largest in the Solar System.
• It is made up of ice elements and rocks. It has a
ring system like Saturn but it is thinner and
darker.
• Its axis of rotation is tilted, almost parallel to its
orbit around the Sun.
• Its has 27 moons orbiting the planet.
Neptune • Eighth planet from the Solar System.
• Methane gives a blue colour to Neptune.
• Takes the longest time to orbit the Sun which is
165 years (Earth time).
• Being the farthest in the Solar System, the
temperature on its surface is extremely cold at
approximately -201°C.
The Differences Of Meteoroid, Asteroid
And Comet
Meteoroid Meteoroid are fragment of rock and metal originating
Asteroid from debris of asteroids or comets that orbit the Sun.
• The measurement of its size varies, from as fine as
sand until it reaches 1 metre only.
• Made up of rocks and metals such as iron and
nickel.
• Its surface temperature in outer space is within
0°C.
• Meteoroids move freely in space and are
influenced by the planets’ and moons’ gravity
around them.
• The speed varies. The fastest movement of
meteoroid is 42 km s-1.
Asteroids are large rocky and metal objects in the solar
system that orbit the Sun.
• The measurement of the diameter is between 1 m
and capable of reaching 1000 km.
• Large asteroids are also known as planetoids
(small planets).
• Consists of metal and rock.
• Asteroids can be categorised into three groups
based on the main compounds they are
comprised of.
• The average temperature on the surface of the
asteroid is -73°C.
• The average speed is 25 km s-1.
• Asteroids are mostly from asteroid belts between
the planets Mars and Jupiter.
• The biggest asteroids are Ceres, Pallas, Juno and
Vesta.
Comet Comets are rocky object made up of a mixture of gas,
ice and frozen dust that travel around the Sun.
• The comet’s structure can be divided into two
parts; the head and the tail.
• The length of the head part can reach 250
thousand kilometres whereas the tail part can
reach 150 million kilometres.
• Made up of gas and water that have become ice
and a little dust and rocks.
• Orbits the Sun in its own orbit that is in the shape
of an ellipse.
• Its average speed is from 10 to 70 km s-1.