Mars
Mars is the fourth planet from the Sun, a cold, rocky world with ancient river valleys; some meteorites come from it.
Mars is a rocky planet about half Earth's width, with a thin atmosphere of mostly carbon dioxide. Its red colour comes from iron oxide dust. Mars has the largest volcano in the Solar System, Olympus Mons, and a huge canyon system, Valles Marineris.
Ancient river valleys, lake beds and minerals that form in water show that Mars was once warmer and wetter. Rovers such as Curiosity and Perseverance are studying these rocks, and Perseverance is collecting samples for possible return to Earth.
Meanwhile, pieces of Mars have already arrived. Impacts on Mars have blasted rocks into space, and a few hundred meteorites found on Earth are Martian: the shergottites, nakhlites, chassignites and a few others. They are identified by their young ages, oxygen isotopes and gases that match the Martian atmosphere. They are the only Martian rocks scientists can study in laboratories today.
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Level: Beginner Ages 7 and up