Facts about Mars   Hubble's close encounter with Mars       Orbit 227 940 000 km (1.52 AU) mean distance from Sun Diameter 6794 km Martian day (sol) 24 hours, 37 mins 22 seconds Martian year 669 Martian days (sols), 687 Earth days Average temperature 218 K (-55 degrees C) Minimum temperature 140K (-133 degrees C) (winter pole) Maximum temperature 300K (27 degrees C) (summer dayside) Surface area 144 x 106 km2, about the same as the land area of Earth Atmospheric pressure at surface 6.35 mbar, that is less than one hundredth Earth's atmospheric pressure. Atmospheric composition 95.32% carbon dioxide, 2.7% nitrogen, 1.6% argon, 0.13% oxygen Moons Phobos - diameter 22 km, orbit 5981 km from surface Deimos - diameter 12 km, orbit 20,062 km         Last update: 19 November 2004 Looking at Mars  •  - (http://www.esa.int/SPECIALS/Mars_Express/index.html) More about...  •  Mars Express mission facts (http://www.esa.int/SPECIALS/Mars_Express/SEMFU55V9ED_0.html) Related articles  •  Mars Express instruments (http://www.esa.int/SPECIALS/Mars_Express/SEMUC75V9ED_0.html)  •  The search for life (http://www.esa.int/esaSC/SEMAGE1P4HD_exploring_0.html)  •  Chances of life are linked to water (http://www.esa.int/esaSC/SEMN3AR1VED_index_0.html)  •  Water on early Mars? (http://www.esa.int/SPECIALS/Mars_Express/SEMKK75V9ED_0.html)  •  Signatures of life (http://www.esa.int/SPECIALS/Mars_Express/SEMSL75V9ED_0.html)  •  Geography of Mars (http://www.esa.int/SPECIALS/Mars_Express/SEMWPNXLDMD_0.html)