Skywatchers, you're in for a treat. Tonight's "supermoon" is a pretty special one.
When the moon turns full on Monday, Sept. 8 at 9:38 p.m. EDT, it not only will become the last supermoon of the summer, but also this year's Harvest Moon -- which is a full moon that occurs closest to the autumnal equinox.
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Supermoons are full moons that coincide with "lunar perigee," when the moon's orbit brings it closest to Earth. This moon appears bigger and brighter than a typical full moon.
Though Monday's supermoon won’t be the largest of the summer's trilogy of supermoons (that distinction went to the full moon of Aug. 10), the coming lunar event is unique in its own way -- it coincides with the Harvest Moon.
For several nights around the time of the Harvest Moon, the moon rises around the same time that the sun sets, giving the moon a reddened, swollen, pumpkin-like appearance. According to NASA, the name comes from the days before the invention of the lightbulb, when moonlight helped farmers reap their crops at this time of year.
On average, the moon usually rises about 50 minutes later than it did the day before, but in the days around the autumnal equinox, that difference decreases to about 30 minutes each night.
If you can't get outside to see it with your own eyes, the SLOOH Space Camera will be hosting a live broadcast of the celestial event (see the livestream video above).