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