You might want to look up (and perhaps howl) at the Moon this Friday night, since you won’t see another full moon like in your lifetime.
On September 13, 2019, at exactly 11:32 p.m. CDT, the Moon turns full just before the stroke of midnight.
Only 1% of full moons occur on Friday the 13th, which in itself is rather rare. This year the full moon on Sept. 13th will be especially rare, since it will happen within 24 hours of apogee (furthest from the earth). The Moon will be at apogee at exactly 7:33 a.m. CDT Friday morning, which is within 24 hours of the full moon on Friday the 13th. The last time this happened was in 1832.
So what is an apogee or micromoon (a.k.a. mini-moon)? The Moon revolves around the Earth in an elliptical orbit, meaning it’s not a perfect circle. One side of the ellipse is closer to the Earth and the other side is farther away.
You’ve probably heard about a supermoon before, which is where the Moon is at its closest point to the earth called perigee. These supermoons are 14% bigger and 30% brighter than an apogee moon, since they are a little over 40,000 kilometers closer to the Earth (approx. 25,000 miles). This makes a big difference in size when viewing from the earth as seen below.
To sum it up, expect to see a smaller than normal (apogee) full moon on the evening of Friday the 13th. We should have adequate viewing with a few high clouds as a cool front begins to wash out from that morning.
While it’s not a super spectacular celestial event, it is a once-in-a-lifetime opportunity. The next “Friday the 13th” micromoon won’t occur until October 2524!