Mars  
Global view of Mars as seen by the Viking 1 orbiter in 1980, showing the Valles Marineris (center)
Designations
Pronunciation i/ˈmɑrz/
Adjective Martian
Orbital characteristics 
Epoch J2000
Aphelion 249,209,300 km
1.665 861 AU
Perihelion 206,669,000 km
1.381 497 AU
Semi-major axis 227,939,100 km
1.523 679 AU
Eccentricity 0.093 315
Orbital period 686.971 days

1.8808 Julian years

668.5991 sols
Synodic period 779.96 days
2.135 Julian years
Average orbital speed 24.077 km/s
Mean anomaly 19.3564°
Inclination 1.850° to ecliptic
5.65° to Sun's equator
1.67° to invariable plane
Longitude of ascending node 49.562°
Argument of perihelion 286.537°
Satellites 2
Physical characteristics
Equatorial radius 3,396.2 ± 0.1 km
0.533 Earths
Polar radius 3,376.2 ± 0.1 km
0.531 Earths
Flattening 0.005 89 ± 0.000 15
Surface area 144,798,500 km2
0.284 Earths
Volume 1.6318×10
0.151 Earths
Mass 6.4185×10
0.107 Earths
Mean density 3.9335 ± 0.0004 g/cm³
Equatorial surface gravity 3.711 m/s²
0.376 g
Escape velocity 5.027 km/s
Sidereal rotation
period
1.025 957 day
24.622 9 h
Equatorial rotation velocity 868.22 km/h (241.17 m/s)
Axial tilt 25.19°
North pole right ascension 21 h 10 min 44 s
317.681 43°
North pole declination 52.886 50°
Albedo 0.170 (geometric)
0.25 (Bond)
Surface temp.
   Kelvin
   Celsius
min mean max
186 K 210 K 293 K
−87 °C −63 °C 20 °C
Apparent magnitude +1.6 to −3.0
Angular diameter 3.5–25.1"
Atmosphere
Surface pressure 0.636 (0.4–0.87) kPa
Composition
  • (mole fractions)
  • 95.32% carbon dioxide
  • 2.7% nitrogen
  • 1.6% argon
  • 0.13% oxygen
  • 0.08% carbon monoxide
  • 210 ppm water vapor
  • 100 ppm nitric oxide
  • 15 ppm molecular hydrogen
  • 2.5 ppm neon
  • 850 ppb HDO
  • 300 ppb krypton
  • 130 ppb formaldehyde
  • 80 ppb xenon
  • 18 ppb hydrogen peroxide
  • 10 ppb methane

Get more info about Mars in Wikipedia

This article uses material from the Wikipedia article
Mars, which is released under the Creative Commons Attribution-Share-Alike License 3.0