Bob Moler's Ephemeris Blog

September 14:  This is Ephemeris for Tuesday, September 14th.* The sun will rise at 7:20. It’ll be up for 12 hours and 34 minutes, setting at 7:55. The moon, 1 day before first quarter, will set at 11:38 this evening. | We’re looking at the moon this week leading up to International Observe the Moon Night Saturday night. We’ll have some telescopes at the Clinch Park Marina Saturday if it’s clear. The moon, even to the unaided eye shows bright and dark areas. The largest bright area to the bottom or south part of the moon is the highlands, a rugged area saturated with craters. The dark areas are generally nearly circular and flat with few craters. These are the maria which is Latin for seas. Which early telescopic viewers thought were really water filled. The seas are gigantic impact basins created by asteroids impacting the moon and their floors are filled with lava from the moon’s interior. They have relatively few craters that occurred later on.

*Times are for the Grand Traverse Area of Northern Michigan, USA.

Moon 1 day before first quarter. Created using Virtual Moon Atlas.