Mass (kg): 4.87 x 1024
Diameter (km) : 12104
Mean density (kg/m3) : 5250
Escape velocity (m/s) : 10400
Average distance from Sun : 0.723 AU (108,208,930 km)
Rotation period (length of day in Earth days) : 243.02 (retrograde)
Revolution period (length of year in Earth days) : 224.7
Obliquity (tilt of axis degrees) : 178
Orbit inclination (degrees) : 3.39
Orbit eccentricity (deviation from circular) : 0.007
Mean surface temperature (K) : 726
Visual geometric albedo (reflectivity) : 0.59
Highest point on surface : Maxwell Montes (17 km above mean planetary radius)
Atmospheric components : 96% carbon dioxide, 3% nitrogen, 0.1% water vapor
Surface materials : basaltic rock and altered materials