Escape Velocity of the Moon

vesc,Moon=2,380 m/sv_{\mathrm{esc},\mathrm{Moon}} = 2,380\ \text{m/s}
Value2,380 m/s
StatusConventional / typical value
SourceDerived from the GRAIL lunar GM and the mean radius
CategoriesAstronomical
Escape Velocity of the Moon in every speed unit
millimeter per year75,107,088,000,000 mm/yr
millimeter per day205,632,000,000 mm/day
millimeter per hour8,568,000,000 mm/h
inch per day8,095,748,000 in/day
foot per day674,645,670 ft/d
inch per hour337,322,830 in/h
meter per day205,632,000 m/d
millimeter per minute142,800,000 mm/min
meter per hour8,568,000 m/h
inch per minute5,622,047.2 in/min
millimeter per second2,380,000 mm/s
foot per minute468,503.94 ft/min
centimeter per second238,000 cm/s
meter per minute142,800 m/min
inch per second93,700.787 in/s
kilometer per hour8,568 km/h
foot per second7,808.399 ft/s
mile per hour5,323.9084 mph
knot4,626.3499 kn
meter per second2,380 m/s
mach (sea level)6.9939523 Ma
kilometer per second2.38 km/s
speed of light0.0000079388255 c

Learning zone

At 2.38 km/s the Moon cannot hold an atmosphere. Gas molecules at lunar daytime temperatures reach a substantial fraction of that speed, so anything released — from outgassing, from comet impacts, from the Apollo landers themselves — escapes within weeks. What remains is an exosphere so thin, around 10⁵ particles per cubic centimetre, that atoms essentially never collide with one another.

The low escape speed is also what made Apollo feasible. The ascent stage carried a single small engine and no heat shield, since there was no atmosphere to slow it and none to fly through; and it is why lunar resources are so often discussed for propellant depots, where launching water or oxygen out of the Moon's shallow gravity well costs a small fraction of lifting it from Earth.