Moon Full moon as seen from North America in Earth 's Northern Hemisphere Designations Adjectives Lunar selenic Orbital characteristics Epoch J2000 Perigee 362 600 km (356 400 -- 370 400 km) Apogee 405 400 km (404 000 -- 406 700 km) Semi-major axis 7008384399000000000 ♠ 384 399 km (7008384466527698999 ♠ 0.002 57 AU) Eccentricity 6998549000000000000 ♠ 0.0549 Orbital period 7006236059151040000 ♠ 27.321 661 d (27 d 7 h 43 min 11.5 s) Synodic period 7006255144288960000 ♠ 29.530 589 d (29 d 12 h 44 min 2.9 s) Average orbital speed 7003102200000000000 ♠ 1.022 km / s Inclination 5.145 ° to the ecliptic Longitude of ascending node Regressing by one revolution in 18.61 years Argument of perigee Progressing by one revolution in 8.85 years Satellite of Earth Physical characteristics Mean radius 7006173710000000000 ♠ 1737. 1 km (0.273 of Earth 's) Equatorial radius 7006173810000000000 ♠ 1738. 1 km (0.273 of Earth 's) Polar radius 7006173600000000000 ♠ 1736. 0 km (0.273 of Earth 's) Flattening 6997119999999999999 ♠ 0.0012 Circumference 7007109210000000000 ♠ 10 921 km (equatorial) Surface area 7013379300000000000 ♠ 3.793 × 10 km (0.074 of Earth 's) Volume 7019219580000000000 ♠ 2.1958 × 10 km (0.020 of Earth 's) Mass 7022734200000000000 ♠ 7.342 × 10 kg (6998123000000000000 ♠ 0.012 300 of Earth 's) Mean density 7003334400000000000 ♠ 3.344 g / cm 6999606000000000000 ♠ 0.606 × Earth Surface gravity 7000162000000000000 ♠ 1.62 m / s (6999165400000000000 ♠ 0.1654 g) Moment of inertia factor 6999392900000000000 ♠ 0.3929 ± 0.0009 Escape velocity 7003238000000000000 ♠ 2.38 km / s Sidereal rotation period 7006236059151040000 ♠ 27.321 661 d (synchronous) Equatorial rotation velocity 4.627 m / s Axial tilt 1.5424 ° to ecliptic 6.687 ° to orbit plane 24 ° to Earth 's equator North pole right ascension 17 47 26 266.86 ° North pole declination 65.64 ° Albedo 0.136 Surface temp. min mean max Equator 100 K 220 K 390 K 85 ° N 150 K 230 K Apparent magnitude − 2.5 to − 12.9 − 12.74 (mean full moon) Angular diameter 29.3 to 34.1 arcminutes Atmosphere Surface pressure 10 Pa (1 picobar) (day) 10 Pa (1 femtobar) (night) Composition by volume He Ar Ne Na Rn
how long is the revolution of the moon
(27 d 7 h 43 min 11.5 s)