| 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 42% 42% 15% 1% | |
Mercury Has No Known Moons
by Calvin J. Hamilton