Mars is the fourth planet from the Sun and is the second smallest planet in the Solar System after Mercury.
Its orbit is more elliptical (non-circular) than Earths, varying between 1.3 and 1.7 times the earths distance from the Sun. Mars takes just under two Earth years to complete its orbit around the Sun. Mars is approximately half
the diameter of Earth, with a surface area only slightly less than the total area of Earth’s dry land.
Mars is less dense than Earth, having about 15% of Earth’s volume and 11% of Earth’s mass, resulting in about 38% of Earth’s surface gravity. Liquid water cannot exist on the surface of Mars due to low atmospheric pressure. However, there is water ice at the poles, and in soil below the surface.
There are currently many missions exploring Mars. Data gathered by these missions
could lead to human exploration of Mars within our lifetimes. These are the main current
missions.
- Nasa’s Perseverance rover has been on Mars now for over one Earth year. It is searching for ancient life and is storing samples of rock and soil to be brought back to Earth. Its Ingenuity helicopter has been tested and flown.
- China’s Tianwen-1 reached Mars orbit in February 2021 and landed in May 2021. Its Zhurong rover is operational.
- The Emirates Hope orbiter again reached Mars in February 2021, and is still sending back data.