The Solar system consists of Sun, nine
planets, asteroids, comets, and meteoroids. We live on Planet Earth. Earth is
one of the 9 planets that go around the sun.
The nine planets are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and
Pluto.Venus, Mars, Jupiter and Saturn look like bright stars from the Earth.
Mercury can be seen early in the evening just after sunset or in the early morning just
before sunrise.
Uranus, Neptune and Pluto are very dim. You really need a telescope to see
them. Mercury is closest to the sun, yet it is 36 millions of miles away from the
sun. As it is close to the sun, it is very hot in Mercury. Mercury and Venus
are the hottest planets. Temperatures in Mercury are over 662 degrees Fahrenheit (350
degrees Celsius).
Pluto is 3,600 million miles away from the sun. Pluto and Neptune are far away
from the sun. That is why they are the coldest planets. Temperatures on these
planets are about 328 degrees below zero Fahrenheit (200 degrees below zero Celsius).
Sun is huge and its diameter is 865,000 miles. Four planets Mercury, Venus,
Mars and Pluto are smaller than Earth. Four planets Jupiter, Saturn, Uranus and
Neptune are larger than Earth. Mercury, Venus, Earth and Mars, closest planets to
earth are known as Earth-like planets. They are solid and made of rock and metal.
Jupiter, Saturn, Uranus and Neptune are known as Jupiter-like planets. They are
huge and made of gas. Jupiter is the biggest of all the planets, and its diameter is
88,000 miles. It is much bigger than Earth, and Earth’s diameter is 8,000
miles. Pluto is the smallest planet.
Orbits
Planets move in paths around the sun called orbits. Earth takes about a year to go around
the sun. Mercury takes 88 days to go around the sun. Pluto takes a long time, 248 years to
go around the sun once.
See how long each planet takes to go around the sun :
| Planet |
Time taken to go around the sun once |
| Mercury |
88 Days |
| Venus |
About 225 Days |
| Earth |
About 365 Days |
| Mars |
687 Days |
| Jupiter |
About 12 years |
| Saturn |
About 29 years |
| Uranus |
About 84 years |
| Neptune |
About 165 years |
| Pluto |
About 24 years |
Earth is the only planet where people, plants and animals live. No other
planet has any life. Earth with people, plants is sometimes called Life Planet.
Satellites or Moons
Moon goes around the Earth. Moon is sometimes called Earth’s Satellite. Moon
goes around the earth about once each month. The moon is 237,000 miles away from
Earth.
Many of the other planets have satellites, but you need a telescope to see them.
Jupiter has 16 satellites or moons. Saturn has more than 20 moons orbiting Saturn.
Asteroids, Comets and Meteoroids
Asteroids are big chunks of rock that go around the sun, mainly between the orbits of
Mars and Jupiter. This region is called Asteroid belt. Many of the asteroids
are quite big and some of them are big as a mountain or even bigger.
Comets are huge collections of ice, gas and dust, traveling in narrow elliptical
orbits. A comet, as it gets close to the Sun, develops a tail as the ice that makes up
most of it vaporizes into space. When a comet approaches Earth, it will look like a
bright, long, glowing tail stretching in the sky.
Meteoroids are bits of rock and metal. Most meteoroids are small as grains of
sand. You might have seen them as shooting stars. They are not really stars.
They are meteoroids falling towards earth.
Way out beyond all the planets are millions of stars. Stars are hot
bodies like sun. They are very far away from us. |
