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Planets and moons


Mars, featuring Valles MarinerisMars, featuring Valles Marineris Mars is the fourth planet from the Sun. A barren planet, its reddish colour comes from iron oxide dust (familiar to us as rust). Immense storms occasionally blow up, blanketing the entire planet with dust. Large dark patches that appear from time to time are areas of rock exposed when storms remove the dust. Mars is known as the “Red Planet”, but not all of it is red. Both poles are white: they have caps of water ice and carbon dioxide ice.

Photo of Martian landscape taken by Curiosity rover Photo of Martian landscape taken by Curiosity rover

This crater on Mars contains water iceThis crater on Mars contains water ice

Similarities with Earth

Mars has a number of features in common with Earth. On Mars there are volcanoes, mountains, dried-up river beds, canyons, deserts and polar ice caps. The Martian day is only a little longer than ours, and the angle of tilt means that Mars has four seasons, just as on Earth. Although average temperatures are a lot colder than on Earth, daytime temperatures at the equator can sometimes reach 35°C (95°F) in midsummer. Thin clouds and early morning surface frosts, made of frozen carbon dioxide, sometimes appear.

Phobos, one of the Martian moons, will collide with Mars in about 50 million years' time.

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