Keep your eyes on the skies during the full moon later this month -- because you could see something that hasn't happened for more than 30 years, and won't happen again for nearly 20 more.
It's a supermoon and a lunar eclipse at the same time, and it'll be visible in much of the world on the night of Sept. 27 in North and South America and the morning of Sept. 28 in Europe, Africa and parts of Central Asia (sorry, Asia-Pacific -- most of you will miss out on this one).
A supermoon is a full moon that takes place when our celestial companion is at its closest point in its elliptical orbit. As the NASA video above explains, a supermoon can appear up to 14 percent larger in diameter than a normal full moon.
The space agency also created a chart showing where the eclipse will be visible:
The last time a supermoon and lunar eclipse happened at the same time was in 1982. The next won't occur until 2033.
This one will begin in the United States at 6:07 p.m. PT/9:07 p.m. ET on Sept. 27, with the total eclipse taking place a little more than an hour later and lasting for more than an hour, according to EarthSky, which has a list of eclipse times across all U.S. zones here.
EarthSky also points out that this won't just be a supermoon and lunar eclipse on the same night. It will also be the harvest moon, or the full moon closest to the autumnal equinox.
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