Even though the Earth and the Moon have been bombarded by the same flux of impacting objects, the evidence…
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Can Two Moons Which Orbit a Planet Eclipse One Another?
Yes, two moons orbiting a planet can eclipse one another, but I think it would be difficult for the…

Occultation of Mars by the Moon
The occultation video you point to looks completely normal, showing only a zoomed-in portion of the disk of the…

How Long Does a Full Moon Last?
Technically, the point at which the Moon is “full” lasts only an instant. To the naked eye, though, the…

Can One Measure Lunar Nodal Positions with a Sundial?
I can’t think of a way to measure the lunar nodal positions with a sundial. The Moon’s nodal points…

Shape and Orientation of the Third-Quarter Moon
The orientation of the illuminated portion of the Moon when it is at third quarter depends upon where on…