Mercury

Mercury Statistics
 Mass (kg) 3.303e+23 
 Mass (Earth = 1) 5.5271e-02 
 Equatorial radius (km) 2,439.7 
 Equatorial radius (Earth = 1) 3.8252e-01 
 Mean density (gm/cm^3) 5.42 
 Mean distance from the Sun (km) 57,910,000 
 Mean distance from the Sun (Earth = 1) 0.3871 
 Rotational period (days) 58.6462 
 Orbital period (days) 87.969 
 Mean orbital velocity (km/sec) 47.88 
 Orbital eccentricity 0.2056 
 Tilt of axis (degrees) 0.00 
 Orbital inclination (degrees) 7.004 
 Equatorial surface gravity (m/sec^2) 2.78 
 Equatorial escape velocity (km/sec) 4.25 
 Visual geometric albedo 0.10 
 Magnitude (Vo) -1.9 
 Mean surface temperature 179°C 
 Maximum surface temperature 427°C 
 Minimum surface temperature -173°C 
 Atmospheric composition
Helium
Sodium
Oxygen
Other

42% 
42% 
15% 
1% 

Mercury/UIUC/sulfridg@uiuc.edu /revised August 98