Properties of the Moon and the Earth-Moon system
Table
Properties of the Moon and the Earth-Moon system
Moon Earth approximate ratio (Moon to Earth)
mean distance from Earth (orbital radius) 384,400 km -- --
period of orbit around Earth (sidereal period of revolution) 27.3217 Earth days -- --
inclination of equator to ecliptic plane (Earth's orbital plane) 1.53° 23.45° --
inclination of equator to body's own orbital plane (obliquity to orbit) 6.68° 23.45° --
inclination of orbit to Earth's Equator 18.28°-28.58° -- --
eccentricity of orbit around Earth 0.0549 -- --
recession rate from Earth 3.8 cm/year -- --
rotation period synchronous with orbital period 23.9345 hr --
equatorial radius 1,738 km 6,378 km 1:4
surface area 37,900,000 km2 510,066,000 km2 (land area, 148,000,000 km2) 1:14
mass 0.0735 × 1024 kg 5.976 × 1024 kg 1:81
mean density 3.34 g/cm3 5.52 g/cm3 1:1.7
mean surface gravity 162 cm/sec2 980 cm/sec2 1:6
escape velocity 2.38 km/sec 11.2 km/sec 1:5
mean surface temperature day, 380 K (224 °F, 107 °C); night, 120 K (-244 °F, -153 °C) 288 K (59 °F, 15 °C) --
temperature extremes 396 K (253 °F, 123 °C) to 40 K (-388 °F, -233 °C) 331 K (136 °F, 58 °C) to 184 K (-128 °F, -89 °C) --
surface pressure 3 × 10-15 bar 1 bar 1:300 trillion
atmospheric molecular density day, 104 molecules/cm3; night, 2 × 105 molecules/cm3 2.5 × 1019 molecules/cm3 (at standard temperature and pressure) about
1:100 trillion
average heat flow 29 mW/m2 63 mW/m2 1:2.2
See as table: