Coming this Friday night: the spookiest full moon in 13 years, and the first Friday the 13th full moon since January 2006.
This full moon, most commonly known as the harvest moon, will appear much smaller than most. That’s because the moon will be at apogee, or the farthest point in its roughly four-week orbit. Timeanddate.com estimates a ‘‘micromoon’’ appears 14 percent smaller and 30 percent dimmer than the widely reported ‘‘supermoons’’ that dominate the news.
Though there is no universal definition governing what qualifies as a supermoon or micromoon, Time and Date says micromoons must be more than 251,655 miles away from Earth. Friday night’s moon will be 816 miles farther than that.
Supermoons, on the other hand, must be at least 2,039 miles closer to Earth than a micromoon. Most of the time, the moon sits somewhere in between those bounds.
This Friday the 13th full moon won’t technically reach peak illumination until 12:32 a.m. Eastern time on Saturday, but for all practical purposes is considered full Friday night. This was also the case in January 2006, when the moon rose the night of the 13th but became full at 4:48 a.m. on Saturday, the 14th.
The next time we’ll have a moon approaching fullness on Friday the 13th (before achieving total illumination the next morning) will be in a little over 13 years, in May 2033.