Tonight's rare Harvest Moon is the closest to the autumnal equinox, the official start of fall. This moon rises earlier at night than other moons, which provides extra light to farmers. EarthSky reports that because the Harvest Moon initially rises closer to twilight, you may see what looks like multiple full moons in the sky. This year's Harvest Moon is especially significant because it coincides with the final lunar eclipse of 2016, which is a penumbral, or partial, eclipse. While most people will enjoy tonight's Harvest Moon, the penumbral lunar eclipse will only be visible in the Eastern Hemisphere.