The Thinnest of Crescent Moons

This is the crescent moon as seen last night, Wednesday, at our observing session.  The moon was very close to the horizon by the time it was dark enough to see it.  The moon orbits the Earth once every 27.322 days and it begins its journey each month at New Moon, when it is close to the Sun, or, as it did on Monday, when it eclipsed the Sun.  Each day, the Moon moves further from away from the Sun by about 13 degrees.  It is fun for some amateur astronomers to see how soon they can see the thin crescent moon, after New Moon.  The sighting of the lunar crescent within one day of New Moon is usually difficult. The crescent at this time is quite thin, has a low surface brightness, and can easily be lost in the twilight. With all the pollution in the air in our area, it is really rare to see even a two-day old moon.  This Moon is 2.3 days old, so I am thrilled to have seen it.