02/07/2023 – Ephemeris – A new view on the creation of our Moon

Feb 7. This is Bob Moler with Ephemeris for Tuesday, February 7th. Today the Sun will be up for 10 hours and 5 minutes, setting at 5:59, and it will rise tomorrow at 7:53. The Moon, 2 days past full, will rise at 7:58 this evening.

Is this how the Moon came to be? After the Apollo missions, NASA decided to look at the crust of the Moon which apparently is much like the Earth’s and came up to the conclusion that the Moon was formed by a collision with the Earth by a Mars sized body that they’ve called Thea, named after the mother of the twins Apollo and Artemis. It crashed into the Earth at about a 45-degree angle, and caused a ring of debris around the Earth that would be maintained for a long time. In a newer simulation, the collision could actually create two blobs of material, a large one that became our Moon, in orbit, with about one percent of the Earth’s mass, and a smaller mass that fell back onto the Earth.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT –5 hours). They may be different for your location.

Addendum

A new simulation on how the Moon formed. Credit: PBS.