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07/08/2014 – Ephemeris – Why are the near side and the far side of the moon so different?
Ephemeris for Tuesday, July 8th. Today the sun will be up for 15 hours and 23 minutes, setting at 9:29. The moon, 3 days past first quarter, will set at 3:27 tomorrow morning. Tomorrow the sun will rise at 6:06.
We’re all familiar with the gray blotches on the moon called seas that make up the face of the Man in the Moon. The other side, the far side, misnamed the dark side, has only one small sea. Astronomers have wondered why. Seems that it’s a product of the Moon’s birth and the late heavy bombardment that came later. In a new hypothesis, a Mars sized proto-planet hit the proto-Earth with a glancing blow peeling off material that fell into a disk that coalesced into the Moon, a lot closer to the earth than it is today, and the far side contained thicker light crustal material than the near side. When the giant planets began their migration much asteroidal material struck the moon. Near side impacts penetrated into the Moons magma, while the far side impacts did not.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

