3. The Milky Way - our Galaxy
• The Milky Way is
one of billions of
Galaxies in the
observable
universe.
• Our solar system
is one of millions
in the galaxy that
has a star in its
centre.
4. • All Solar systems have a Star at their centre and ours is called
the Sun, which all the Planets revolve around by the means of
gravity.
5. • The sun is the
biggest, brightest, and
hottest object in the solar
system.
• The sun is an ordinary
star.
• The sun is made of about
70% hydrogen and 28%
helium.
Surface temperature:6,000 ºC
Age:4.5 billion years (approx)
Distance from Earth:150 million km
Diameter:1.4 million km
Core temperature:15 million ºC
6. • Mercury is solid and is
covered with craters.
• Mercury has almost no
atmosphere.
• Mercury is the eighth
largest planet.
Discovered:Known since 3,000 years BC
Diameter:4,900 km
Temperature on surface:-173 degrees Celsius -
425 degrees Celsius
Surface gravity:3.7 m/s2
Distance from the Sun:46 - 69 million km
Time taken to rotate on axis: 58 Earth days
Time taken to orbit Sun: 88 Earth days
Moons:None
7. • Venus is the sixth
largest planet. It’s
about three-fourths
the size of earth.
• The surface is rocky
and very hot. The
atmosphere
Discovered:Known since 3,000 years BC
Diameter:4,900 km
completely hides the
Temperature on surface:-173 degrees Celsius - 425 degrees Celsius
Surface gravity:3.7 Discovered: In the prehistoric age surface and traps the
Diameter:12,100 km
Temperature on surface:462 °C heat.
Surface gravity: 8.87 m/s2
Distance from the Sun:Varies between 107 - 109 million km
Time taken to rotate on axis:243 Earth days
Time taken to orbit Sun:224.7 Earth days
Satellites:None
Distance from the Sun:46 - 69 million km
Time taken to rotate on axis: 58 Earth days
Time taken to orbit Sun: 88 Earth days
8. • Earth is the fifth largest planet and the third from the sun.
• Liquid covers 71 percent of the Earth’s surface.
• The Earth has one moon.
Age: 4.6 billion years
Diameter: 12,700 km
Temperature on surface: -88 C to 58 C
Surface gravity: 9.81m/s2
Distance from the Sun: 150 million km
Time taken to rotate on axis: 23.9 hours
Time taken to orbit the Sun: 365.26
Earth days
Moons: The Moon
9. • The Moon controls our oceans and tides.
• The Moon is approximately quarter the size of the
Earth.
Age:4.6 billion years
Diameter:3,480 km
Temperature on surface:Varies from
-233 °C to 122 °C
Distance from the Earth:About 386,200 km
and orbits the Earth every 28 days.
Satellites:None
10. • Mars is the fourth
planet from the sun.
• Mars has a thin
atmosphere that
contains mostly
carbon dioxide.
• Mars has two small
moons.
Discovered:Prehistoric times
Diameter:6,787 km
Temperature on surface:Between -153 °C and 30 °C
Distance from the Sun:Varies between 206 and 249
million km
Satellites:2, Phobos and Deimos
11. • The Asteroid belt is situated between Mars and
Jupiter.
Discovered:Early 19th century
Distance from the Sun:Varies
between 387million km and 489
million km
Asteroids:are irregular fragments of
rock left over from the formation of
the Solar System 4.6 billion years ago
12. • The Great Red Spot, a
huge storm of swirling gas
that has lasted for
hundreds of years.
• Jupiter does not have a
solid surface. The planet is
a ball of liquid surrounded
by gas.
• Jupiter is the largest planet Discovered:Prehistoric times
Diameter:143,000 km
in the Solar System. Temperature:-150 °C (in the
atmosphere)
Distance from the Sun:Varies between 740 -
817 million km
Satellites:63 known including Io, Ganymede,
Europa and Callisto
13. • Saturn is the second largest
planet and the sixth from the
sun.
• Saturn is made of materials
that are lighter than water. If
you could fit Saturn in a
lake, it would float!
• Saturn is distinctive because
of its rings.
Discovered:Prehistoric times
Diameter:120,000 km
Temperature:-130 °C (at cloud tops)
Distance from the Sun:Varies between
1,351 and 1,510 million km
Moons:52 officially named (and counting)
including Titan
14. • Uranus is the third largest
planet and the seventh
from the sun.
• Uranus is one of the giant
gas planets.
• Uranus is blue-green
because of the methane in
its atmosphere.
Discovered:1781 by William Herschel from
Bath, England
Diameter:51,499 km
Temperature:-210 ºC (at cloud tops)
Distance from the Sun:Varies between 2.7 and
3 billion km
Satellites:27
15. • Neptune is the fourth
largest planet and the
eighth from the sun.
• Because of the orbits, from
1979 to 1999, Neptune
was the ninth planet.
• Like Uranus, the methane
gives Neptune its color.
Discovered:1846 (proved mathematically 1845)
Diameter:49,500 km
Temperature:-220 °C (at cloud tops)
Distance from the Sun:Varies between 4.46
and 4.54 billion km
Satellites:13
16. • Pluto is the smallest planet
and usually the farthest
from the sun.
• Pluto is the only planet that
has not been visited by a
spacecraft.
Discovered:1930
Diameter:2,301 km
Temperature on surface:-235 °C to -210 °C
Distance from the Sun:Varies between 4.3 and
7.4 billion km
Satellites:3
