We call Mars the red planet.
It looks like a bright red light at night. The color comes from minerals on its surface. Those are mostly iron oxide and olivine. Astronomers used to think intelligent beings might live on Mars. Science fiction authors wrote stories about invaders from Mars, or Martians.
Actually, Earth is “invading” Mars. We have sent different unmanned spacecraft to visit it. Some studied the planet from orbit. Others made dangerous landings, and some have crashed while trying to land.
The spacecraft show us that Mars is a cold, dusty, bare planet. Humans can’t breathe its very thin atmosphere, which is made up mostly of carbon dioxide. Mars is about one and a half times as far from the Sun as Earth. That makes it much colder. A really hot summer day would be only about 70°F. Winter temperatures drop to almost 200 degrees below freezing.
