Astronomy Picture of the Day

Explanation: Does this Moon look a little different to you? Although shown in spectacular detail, the full face of Earth's most familiar satellite appears slightly darker than usual, in particular on the upper left, because it is undergoing a penumbral lunar eclipse. The image was captured in Hong Kong, China, on September 16 when the Moon crossed through part of Earth's shadow -- but not the darkest where the Earth shades the entire Sun. A lunar eclipse can only occur during a full moon, and the full moon of this eclipse was known by many as the Harvest moon for its proximity to northern harvests. The next full moon will occur this coming Sunday and will be referred to in some cultures as a Leaf Falling Moon, named for its proximity to northern autumn. The second full moon of the same month ("moonth") is sometimes called a Blue moon, but this month features a rare second new moon, an event known to some as a Black moon.