Bob Moler's Ephemeris Blog

Ephemeris for Tuesday, September 17th.  The sun will rise at 7:23.  It’ll be up for 12 hours and 24 minutes, setting at 7:48.   The moon, 2 days before full, will set at 6:27 tomorrow morning.

The question of how the moon formed has long been a mystery.  It was considered impossible that the earth could capture such a large body all by itself.  An answer came from the age of the Apollo Moon missions.  Though the moon has a 64th the earth’s volume, it has only an eighty-first of the earth’s mass, hence it was made of lighter material overall than the earth.  The Moon is made of the same material as the crust of the earth.  Even the isotopes of the elements matched, extremely odd if the Moon was the result of a capture or collision with the already formed earth.  A new theory posited last year has the earth and moon forming from a collision of two large-sized bodies, whose material was mixed to then form the Earth and Moon.

Times are for the Traverse City/Interlochen area of Michigan.  They may be different for your location.

Addendum

Collision of Mars sized body with the early Earth. A newer theory posited a more equal sized bodies. Credit: NASA