We all know that we have nine planets in our Solar System. These planets circle around the sun and this is called orbits.
The Inner Solar System has Mercury, Venus, Earth and Mars . These are closest to the sun and are called the terrestrial planets simply because the have very solid rocky surfaces.
The Outer Solar System has Jupiter, Saturn, Uranus, Neptune and are called gas giants.
There is a small planet named Pluto out past Neptune which has ice surface. Many scientist don’t think this as a planet anymore.
- The surface of Mercury is very similar to our moon.
- Being so close to the Sun, the daytime temperature on Mercury reaching over 400 Degrees Celsius.
- At night however, without an atmosphere to hold the heat in, the temperatures dropping to -180 Degrees Celsius.
- Mercury has a very low surface gravity.
- Mercury has no atmosphere which means there is no wind or weather to speak of.
- There is also no water on the surface of Mercury, it is possible however that there could be water underneath the surface.
- Likewise, there is no air on the surface but it could be trapped underneath.
Its size is slightly smaller than Earth.
Venus is surrounded by clouds. These clouds create acid rain. The clouds are so thick that little light even reaches the surface.
The surface of Venus is covered by deserts and active volcanoes.
Venus features no liquid water.
- Earth is unique from all other planets in this respect. Earth is our home.
- 71 per cent of the Earth is covered with water. Earth is the only planet where water can exist in liquid form on the surface.
- The land on Earth is made of several plates and at one time all of these plates were joined together.
- Only 11 percent of the Earth’s surface is used to grow food.
- Antarctica is the coldest place on Earth. The entire continent is made of ice.
- The Earth is orbited by one moon.
Mars is called the red planet because it is covered with dust. Even the atmosphere is a pinkish red
Mars experiences violent dust storms which continually change its surface.
Mars has many massive volcanoes and is home to Olympus Mons, the largest volcano in our solar system, it stands 21km high and is 600km across the base.
Mars has a very thin atmosphere made mostly of carbon dioxide. It is not thick enough to trap the sun’s heat like Venus, so the planet is very cold.
Mars has many channels, plains and canyons on the surface which could have been caused by water erosion in the past.
Mars has very weak gravity which cannot hold onto the atmosphere well