A supermoon occurs when the moon is in its full phase at the same time that it’s at perigee, which is the point in its orbit when it’s closest to Earth.
That’s what will happen tonight (February 19) in the second of three supermoons this year. The full moon will be about 17,000 miles closer to Earth than normal, making it appear up to 14 percent larger and 30 percent brighter, according to NASA.
While the supermoon’s peak was technically at 10:53 a.m. EST, it wasn’t visible. Instead, people can keep an eye on the sky tonight, particularly around moonrise when the moon will be the most impressive. (You can find the moonrise time for your specific location here.)
When the moon is rising in the east as the sun is setting in the west, the moon will appear largest, although that’s mostly an illusion. “Because relatively close objects [like trees or buildings] are in front of the moon, our brain is tricked into thinking the moon is much closer to the objects that are in our line of sight,” NASA astronomer Mitzi Adams told CNET.
Tonight’s lunar display isn’t just a supermoon, either. It’s also what’s known as a snow moon, which is how the Native Americans used to differentiate different moons based on the seasons. Because this one occurs in February, a month that often sees heavier snowfalls, it received the designation of snow moon.
If the weather looks like it will be overcast in your area this evening, you can watch a live broadcast of the event from Rome at The Virtual Telescope Project’s website. Otherwise, you’ll have to wait for the next supermoon, which will take place on March 19, 2019.