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Ephemeris: 07/07/2025 – Old and new explanations of the Moon’s appearance
This is Ephemeris for Monday, July 7th. Today the Sun will be up for 15 hours and 24 minutes, setting at 9:30, and it will rise tomorrow at 6:05. The Moon, 3 days before full, will set at 3:30 tomorrow morning.
The Moon’s changing appearance over the month may seem to be mysterious at first glance. Maybe because one may think that the objects in the sky are somehow different from the familiar objects we see around us on the Earth. In ancient times, especially the Greeks thought that everything in the heavens was perfect and spotless. They explained the definite markings we see as the man-in-the-moon as a reflection of the Earth by a spotless Moon. The Moon’s phases are simply light and shadow on a ball in the sunlight. Sometime, when the Moon appears in the daytime, take a small ball, like a golf ball and hold it up to the Moon, while the ball is also in sunlight, and the small ball will exhibit the same phase as the Moon.
See 10/12/18
The astronomical event times given in this blog are for the Traverse City/Interlochen area of Michigan (Lat 44.7° N, Long 85.7° W; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.
Addendum
05/24/2012 – Ephemeris – Phases and shadows on the moon
Ephemeris for Thursday, May 24th. Today the sun will be up for 15 hours and 8 minutes, setting at 9:13. The moon, half way from new to first quarter, will set at 12:11 tomorrow morning. Tomorrow the sun will rise at 6:04.
The fat crescent moon tonight is like the crescent Venus, with the sun shining on mostly the far side. I notice that some folks think that the earth is casting its shadow on the moon to cause the crescent. That isn’t correct. The earth does cast its shadow on the moon sometimes, but only at full moon, but only about one in 6 full moons, and we usually don’t see many of these. The phases of the moon are simply the light and shadow of a ball in the sunlight. In fact, if before sunset you can see the moon, and you are in sunlight also. Hold the ball up next to the moon. You will see that the ball will have the same phase as the moon. This is because the moon is close to the earth.
Bob Moler's Ephemeris Blog 