Mars is very similar to Earth. Mars' year and day are very similar to Earth compared to other planets.
Mars
Mars.
Earth?
Mars
Mars
Venus, mars.
Mars
mars
Mars
The planet Mars has a very thin atmosphere, similar to the moon.
No. Mars is a rocky planet, similar to earth in some ways. We are attempting at this very moment to determine if there was ever life on Mars, or if Mars could possibly sustain life in the future.
Probably a rocky planet similar to Mars, except smaller. All the asteroids combined are not as much mass as Mars is.