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Dark Skies
Star Parties
Solar System
Light Pollution
<a href='/solarsystem/sun/index.html'>sun</a> Sun
mercury Mercury
venus Venus
earth Earth
mars Mars
jupiter Jupiter
saturn Saturn
uranus Uranus
neptune Neptune
pluto Pluto
Planet Stats
Planet Sizes
Planets & Stars
A Light Year

Mars is our second closest neighbor after Venus.


Mars Statistics

Length of Year 687 days 1.881 x Earth's
Length of Day 24.66 hours 1.029 x Earth's
Diameter 6,746 km 0.533 x Earth's
Mass 6.4219e23 kg 0.107 x Earth's
Orbit 227,940,000 km 1.52 AU
Mean orbital velocity 24.13 km/s 0.810 x Earth's
Gravity   0.379 x Earth's
Average Day temperature -5° C / 20 ° F
Average Night temperature -85° C / -120 ° F
Moons (2) Phobos and Deimos
Atmosphere Very thin carbon dioxide (95.3%)
Mars Calendar of Events 2009
Nov 24, 2009
Mars comes closer than 1.0 AU.
Nov 28, 2009
Apparent brightness of Mars exceeds 0.0 mag.
Dec 1, 2009
Mars leaves constellation Cancer and enters Leo.
Dec 3, 2009
Apparent diameter of Mars exceeds 10".
Dec 21, 2009
Apparent brightness of Mars exceeds -0.5 mag.
Dec 22, 2009
Mars becomes stationary and then starts its retograde opposition loop, as Earth passes between the Red Planet and the Sun.
Jan 1, 2010
Mars shines at mag -0.77 in constellation Leo with an apparent diameter of 12.67". Distance from Earth is 0.73885 AU (111 million km).
Jan 9, 2010
Mars leaves constellation Leo and enters Cancer again, during retograde opposition loop.
Jan 11, 2010
Apparent brightness of Mars exceeds -1.0 mag.
Jan 27, 2010
Closest approach of Mars and Earth (0.664 AU = 99.33 million km). Apparent diameter of Mars is 14.105".
Jan 29, 2010
Mars opposition on Earth, Earth in inferior conjunction on Mars. Apparent brightness of Mars reaches -1.28 mag in constellation Cancer.
Feb 14, 2010
Mars' apparent brightness becomes fainter than -1.0 mag.
Feb 21, 2010
Mars at its greatest northern heliocentric ecliptic latitude (+1.8489 deg).
Mar 5, 2010
Mars' apparent brightness becomes fainter than -0.5 mag.
Mar 11, 2010
Mars becomes stationary to end its retograde opposition loop as the Earth has passed it on its inner orbit, and proceeds in prograde apparent motion.
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