Mars Facts
Mars is the fourth planet from the sun.
Distance from the Sun:
Minimum: 206,000,000 kilometers
Average: 228,000,000 kilometers (1.52 times as far as Earth)
Maximum: 249,000,000 kilometers
Eccentricity of Orbit:
0.093 vs. 0.017 for Earth
(0.00 is a perfectly circular orbit)
Distance From Earth:
Minimum: 56,000,000 kilometers
Maximum: 399,000,000 kilometers
Day:
24.6 Earth Hours (1 Mars day is sometimes called 1 sol)
Year: 1.88 Earth years = 687 Earth days = 669 Mars days
Tilt of Rotation Axis: 25.2° vs. 23.5° for Earth
Size:
Diameter: 6792 kilometers vs. 12,756 kilometers for Earth
Surface gravity: 0.38 (about 1/3) times Earth's gravity
Mass: 6.4 x 1023 kilograms, about 11% of Earth's mass
Density: 3.9 grams/cubic centimeter vs. 5.5 grams/cubic centimeter for Earth
Surface Temperature:
Generally cold.
Global extremes: -125°C (-193°F) to 25°C (77°F)
Average at Viking 1 site: high -10°C (14°F); low -90°C (-130°F)
Atmosphere:
Thin and unbreathable.
Surface Pressure: about 6 millibars, or about 1/200th of Earth's.
Pressure varies with season - during the winter, part of the atmosphere freezes
(as dry ice) onto the polar cap.
Contains 95% carbon dioxide, 3% nitrogen, 1.5% argon, trace amounts of water,
and no oxygen. (Earth has 78% nitrogen, 21% oxygen, 1% argon, and 0.03% carbon
dioxide.)
Surface:
Color: Rust red
Ancient landscape dominated by impact craters.
Tallest volcano in the Solar System: Olympus Mons, 21 kilometers high and 600
kilometers across, the size of the state of Arizona.
Largest canyon system in the Solar System: Valles Marineris, 4000 kilometers
long and up to 11 kilometers deep. If placed on Earth, Valles Marineris would
stretch from California to Washington D.C.
Ancient channels carved by massive floods.
Some rocks are basalt (volcanic lava, as in Hawaii); the composition of other
rocks is unknown.
Dust is reddish, rusty, like soil formed from volcanic rock
Moons:
Phobos ("Fear"), about 21 kilometers across
Deimos ("Panic"), about 12 kilometers across
Both Phobos and Deimos are very irregular in shape
Visitors of This Page Since 9/2/03
