|Distance (Earth Radii)|
As the Moon orbits the Earth the portion we see illuminated changes from day to day. The start of each phase occurs with the new Moon in which the Moon does not appear illuminated from the Earth. The Moon takes 27.3 days to orbit Earth, but the lunar phase cycle (from new Moon to new Moon) is 29.5 days. This is because the Moon spends an extra 2.2 days "catching up" as the Earth travels about 45 million miles around the Sun during the time the Moon completes one orbit around Earth.
Astronomers often refer to a Lunar Calendar to track the phases of the Moon. Generally astronomers do not want to observe the night sky during those times the Moon is highly illuminated because moonlight can obscure the light from fainter objects such as stars, planets, and nebulae. Below is the Lunar Calendar for the current month. Happy Star-Gazing!
Enter a different date in the form of : [jun 23, 1997] or [6/23/1997] or [6/23/97]