Scientists suspect that years ago, life would have appeared on Mars surface. Indeed, fossils would have been found.
But today, Mars is a planet twice smaller tahn Earth, whit a diameter of « 6,794 km ». It's atmosphere is very thin. Like Earth, it turns on it self in a day. It has also four well defined seasons. Gravity is 3,72 m/s².
We find on Mars just carbonic gas,  without any oxygen traces ( more than 95% Co²). The temperature is less than 50° F because of the greenhouse effect and because it's further than Earth from de sun. Its sky is yellow-brown.

There are a lot of wind whit storms and fog. Mars is a rocky planet where we can find extinct volcanos and mountains (like Mount Olympus height « 25km ») The irruptions of the last years dug caves underground. We can find-less than one meter of the ground water in the form of ice...
Like Earth, Mars has got two poles covered whit ice, which regress in summer and are reinforced in winter. But Mars, before all, is a desert planet : her surface, equal to all terrestrail continents, is only an immense expance of stand and rocks