WHAT IS MARS LIKE? Mars is a very cold desert world, with average temperatures of -60 degrees Celsius. Like Earth, Mars has seasons, polar ice caps, volcanoes, canyons, and weather, according to NASA. It has a very thin atmosphere made of carbon dioxide, nitrogen, and argon. There are signs of ancient floods on Mars, but now water mostly exists in icy dirt and thin clouds. On some Martian hillsides, there is evidence of liquid salty water in the ground.
NASA/ JPL/ Malin Space Science Systems