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  • Mars is about half the size of Earth and has about one-tenth the Earth's mass.

  • Mars has 37% the gravity of Earth's surface, meaning you could jump 3 times higher on Mars than you can on Earth.

  • At a height of about 13.6 miles, Olympus Mons is the tallest peak and largest volcano in the solar system. For reference, it is 2.5 times as tall as Mt. Everest.

  • olympus mons
    An orbital view of Olympus Mons taken by the Viking 1 probe.
  • Mars' dust storms are the largest in the solar system and can cover the planet for entire months.

  • While Mars' atmospheric composition is similar to that of Venus, its thin atmosphere means that temperatures never exceed 68 degrees Fahrenheit.

  • Mars orbiters have found rock channels that could only have formed in the presence of water. It is believed that Mars once had abundant water. One theory for why the water has largely disappeared is that it was ejected into space after Mars was impacted by a large body.

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    An artist's rendition of Mars billions of years ago.
    polar cap.
    Mars northern polar ice cap in early summer. Mars is the only planet besides Earth that has polar ice caps.
  • While the presence of frozen water on Mars has been known for a long time, scientists only recently discovered flowing water.

  • water on Mars
    Salty liquid water flowing on Newton Crater during the warm season.
    The Valles Marineris on Mars, shown here, is the largest canyon in the solar system. Far outpacing the Grand Canyon, the Valles Marineris stretches 2,500 miles long, reaches a maximum width of 125 miles and is 6 miles deep in some parts.
    Mt. Sharp is one of Mars' most impressive geological features. The picture has been white balanced to show how it would apppear if it was on Earth.
  • Of the dozens of missions to Mars, only 18 missions have been successful.

  • viking first pic
    The Viking 1 was the first probe to land on Mars. On the right is the first color image sent back from Mars' surface.

    360-degree view of Mars' surface. Taken by the Curiosity rover at the Rocknest sand patch.

    Colonization of Mars has long been a dream of scientists and novelists.

    Concept art for a Mars Colony.
  • However, as the book/movie 'The Martian' so deftly illustrates, colonization would be no easy feat. Settlers would have to deal with radiation, low gravity, growing food, making water and fuel, toxic perchlorate in the soil among many other issues. NASA's goal is to get humans to Mars sometime in the 2030s.

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    Sunset on Mars. Taken by the Spirit rover at Gustav Crater.


  • Mars has two moons: Phobos and Deimos.

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    Mars' heavily cratered, potato-shaped moon Phobos.
  • Phobos orbits just 3,700 miles away from Mars closer, making it the closest orbit of any moon in the solar system.

  • Phobos is doomed! In 30-50 million years, it will collide with Mars and be torn apart by the planet's tidal forces. This might create a ring.

  • Phobos has been proposed as a forward operating base for a future Mars mission.

  • Mars' tiny moon Deimos is smoother than Phobos.
  • Deimos orbits about Mars about 3 times as far as Phobos does and is about half the size of Phobos.

  • While Phobos is expected to crash into Mars, Deimos is slowly drifting away from its home planet.


By Aaron Feigenbaum