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astronomymars (Mars ** )

Astronomy — The Planet Mars


  • Distance from the Sun:  141,600,000 miles
  • Time for one solar circuit, in Earth days:  687 days
  • Time for one axial rotation, in Earth days:  25 hours
  • Diameter:  4,000 miles
  • Surface temperature range:  -200° F to 80° F
  • Atmosphere:  A thin layer of atmosphere of CO2 (95% carbon dioxide, 3% nitrogen, 2% argon)
  • Mars’ axis of rotation is tipped 24° (Earth’s axis is tipped 23.5°).  Hence, Mars has “seasons”, similar to Earth.
  • Mars has two moons.  Phobos, with a diameter of 18 miles and Deimos, with a diameter of 8 miles).
  • Mars has polar caps which grow each “winter” and diminish each “summer”.
  • Mars had a period of volcanism which lasted 3 billion years.  Mt. Olympus, an inactive volcano, is 16 miles high (84,000 feet) and 370 miles wide at its base.  By comparison, Mauna Loa in Hawaii is 6 miles high and 140 miles wide.
  • The Martian valley, Valles Marineris, is 2500 miles long, 120 miles wide, and 4 miles deep.
  • Water was plentiful on Mars at one point in its’ history.
  • Mars has no appreciable magnetic field.  Thus, it probably has no metallic core.
  • The red tint of Mars, as seen from Earth, is due to the iron oxides in the Martian soil.
  • There is enough frozen water in Mars’ crust to cover the planet to a depth of 400 meters (Earth’s water could cover it to a depth of 3 kilometers).
  • In our solar system, Mars has the largest impact crater (Hellas, 1000 miles across), the largest canyon (Valles Marineris, 2500 miles long and 4 miles deep), and the largest volcano (Mt. Olympus, see above).

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