How big is Mars? How big is Earth? Why is Mars' atmosphere so thin?

Mars has a variety of terrains, just like Earth, including mountains, plains, and canyons. Due to factors such as lower gravity, the size of the terrain is different from that of Earth. How big is Mars and how big is Earth? Today, let's take a closer look.

Contents of this article

1. How big is Mars? How big is Earth?

2. Why is the atmosphere of Mars so thin?

3. Area of ​​Mars

How big is Mars? How big is Earth?

Mars has a mass of 6.4171x1023 kg and a diameter of 6779 km, while Earth has a mass of 5.97237x1024 kg and a diameter of 12756 km. Mars has a mass of about 11% of Earth and a diameter of about 53%. In addition, Mars' axial inclination and rotation period are similar to those of Earth, and its revolution period is twice that of Earth.

The inclination of Mars' rotation axis is 25.19 degrees, similar to that of the Earth, so it also has four seasons, but the length of the seasons is about twice as long.

The volume of the Earth is 1.0832073×10^12km³, with an average density of 5507.85 kg/m³. It is the terrestrial planet with the largest diameter, mass and density in the solar system.

Why is Mars' atmosphere so thin?

The thinness of Mars' atmosphere is related to its mass, gravity, magnetic field and other factors. Generally speaking, the size of mass affects the size of gravity. Mars' mass is too small, and its gravity is not enough to bind the molecules in the atmosphere. The escape velocity of the molecules is relatively fast, which leads to the thinness of Mars' atmosphere.

The magnetic field on Mars is also a major reason. The magnetic field on Mars is weak, and most of the charged particles in the solar wind can enter the Martian atmosphere and excite the energy of molecules in the atmosphere, causing the molecules to quickly escape into outer space.

There is currently no evidence that there are any hot spots active on Mars recently, and without volcanic activity, there will be no gas replenishment, so the loss rate of air molecules in the atmosphere will be greater.

Although Mars has an atmosphere, its density is only 1% of Earth's atmosphere, and its main component is carbon dioxide, which accounts for 95%. The air on Mars is not suitable for direct breathing.

Mars area

The surface area of ​​Mars is about 28% of the Earth, which is about 510,109,340 square kilometers. So the area of ​​Mars is about 142,828,261 square kilometers, which is much smaller than the Earth.

Mars is about half the diameter of Earth, 15% of its volume, 11% of its mass, and has a surface area equivalent to Earth's land area.

Mars has a variety of terrain like Earth, with mountains, plains and canyons. Due to factors such as lower gravity, the size of the terrain is different from that of Earth in many places.

Mars is basically a desert planet, with sand dunes and gravel all over the surface. There is no stable liquid water, and sandstorms often occur every year. Most of the surface landforms are densely packed with craters, volcanoes and canyons.