Orbital Mechanics
Section M 3.12.
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Lunar Orbital Libration

      Lunar equator is tilted 1 deg 32 min from the ecliptic
      Lunar equator is tilted 6 deg 41 min from its orbital plane
      Orbital plane is titled 5 deg  9 min from ecliptic
The moon's orbit and inclinations

Longitudinal libration, due to elliptical orbit of the moon about the Earth, is 7.7 deg. From the point of view of an observer on the moon, that makes Earth rock back and forth in the sky, east to west.

Latitudinal libration, due to the tilt of the moon's axis with respect to the ecliptic, will cause the Earth to oscillate north and south by 6.7 deg each way.

So, from a point on the moon, the Earth will always be found somewhere in a box 15.4 deg wide and 13.4 deg high. Earth's diameter subtends about 2 deg.

Lunar libration does have implications regarding antenna beam spread and transmission efficiency for beaming information to Earth over long periods of time. At the very least, it means the equipment moving an Earth-tracking antenna could be fairly simple (no rotating electrical or fluid joints, just flex cables), and the antenna's slew rate would be very slow.

From the point of view of someone on Earth, longitudinal libration means we get a peek at the lunar farside 7.7 deg past 90 deg east and west longitude as it goes through its 29-day orbit about the Earth. This means Mare Crisium will sometimes be rather prominent in the northeastern quadrant, and sometimes turned away from us more.

Diurnal libration, as seen from Earth due to rotation of the Earth, is 1 deg at western edge when moon is rising and 1 deg at eastern edge when moon is setting. (That's because of the diameter of the Earth; doesn't contribute to Earth wobbling in lunar sky.)

Actually, the average lunar month in time it takes to go around Earth is 29.531 days, plus or minus 13 hours depending on the moon goddess's mood. Now, this is tricky. The period of the moon's orbit with respect to the stars is 27.322 days; that's a sidereal month.

For completeness: the moon's orbit has a perigee of 356,410 km and an apogee of 406,697 km. Its mean radius is 1,738 km (and very round, albeit bumpy; flattening is only 0.0005 compared to Earth's 0.0034; that's the price our home planet pays for being such a dervish), mass 7.353E22 kg, escape velocity at the surface at the equator 2.38 km/sec, gravity at the equator 1.62 m/sec^2.

Orbital Mechanics

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