Orbit Of The Moon
The Moon completes its orbit around the Earth in approximately 29.5 days (a synodic month). The Earth and Moon orbit about their barycentre (common centre of mass), which lies about 4600 km from Earth's centre (about three quarters of the Earth's radius). On average, the Moon is at a distance of about 385000 km from the centre of the Earth, which corresponds to about 60 Earth radii. With a mean orbital velocity of 1,023 m/s, the Moon moves relative to the stars each hour by an amount roughly equal to its angular diameter, or by about 0.5°. The Moon differs from most satellites of other planets in that its orbit is close to the plane of the ecliptic, and not to the Earth's equatorial plane. The lunar orbit plane is inclined to the ecliptic by about 5.1°, whereas the Moon's spin axis is inclined by only 1.5°.
| Property | Value |
|---|---|
| Semi-major axis | 384748 km |
| mean distance | 385000 km |
| inverse sine parallax | 384400 km |
| Distance at perigee | ~362600 km (356400 – 370400 km) |
| Distance at apogee | ~405400 km (404000 – 406700 km) |
| Mean eccentricity | 0.0549006 (0.026 – 0.077) |
| Mean inclination of orbit to ecliptic | 5.14° (4.99 – 5.30) |
| Mean obliquity | 6.58° |
| Mean inclination of lunar equator to ecliptic | 1.543° |
| Period of precession of nodes | 18.5996 years |
| Period of recession of line of apsides | 8.8504 years |
Read more about Orbit Of The Moon: Properties, History of Observations and Measurements, Lunar Periods, Tidal Evolution, Libration, Path of Earth and Moon Around Sun
Famous quotes containing the words orbit of the, orbit of, orbit and/or moon:
“The Fitchburg Railroad touches the pond about a hundred rods south of where I dwell. I usually go to the village along its causeway, and am, as it were, related to society by this link. The men on the freight trains, who go over the whole length of the road, bow to me as to an old acquaintance, they pass me so often, and apparently they take me for an employee; and so I am. I too would fain be a track-repairer somewhere in the orbit of the earth.”
—Henry David Thoreau (1817–1862)
““To my thinking” boomed the Professor, begging the question as usual, “the greatest triumph of the human mind was the calculation of Neptune from the observed vagaries of the orbit of Uranus.”
“And yours,” said the P.B.”
—Samuel Beckett (1906–1989)
“The Fitchburg Railroad touches the pond about a hundred rods south of where I dwell. I usually go to the village along its causeway, and am, as it were, related to society by this link. The men on the freight trains, who go over the whole length of the road, bow to me as to an old acquaintance, they pass me so often, and apparently they take me for an employee; and so I am. I too would fain be a track-repairer somewhere in the orbit of the earth.”
—Henry David Thoreau (1817–1862)
“The moon sees nothing of this. She is bald and wild.”
—Sylvia Plath (1932–1963)