It’s been a long wait, but we finally have an eclipse worth setting the alarm for. But it’s oh-so-odd, just the kind of thing we need right around now.
The past few years we’ve had a unique series of penumbral lunar eclipses — the kind where the full Moon doesn’t change its appearance. Meaning, they were eclipses in name only. We’ve been stuck with one after another of these nothingburger events, and when a genuine visible lunar eclipse finally did happen this past May, it wasn’t visible from here. But Thursday night (Friday morning) our luck changes. We’ll finally get the real deal.
It’s actually a partial lunar eclipse, with the partial part beginning at 2:18 a.m. Thursday night, the 18th. And this is where the first oddity kicks in: since it’s after midnight it’s really happening during the first early hours of Friday, November 19th so make sure you set the alarm on the correct night. When it rings, look out a window facing the southwest, and the first dot of Earth’s shadow will start touching the Moon at 2:18.
For the next hour and a half the Moon will get increasingly blacked out, until at very nearly 4 a.m. EST the eclipse will reach its maximum. So that’s the sweet spot, the wee hours of Friday morning, November 19th, with the Moon now lowish in the west and looking distinctly reddish since Earth casts a red shadow into space.
Maybe you feel an initial disappointment that the Moon will not get totally eclipsed. Because when it comes to solar eclipses, totality is everything. It’s super important because that’s when all the fantastic stuff happens. But not with the Moon. At 4 a.m. the Moon will be more than 95 percent covered by Earth’s shadow, yet that’s enough to deliver all the visceral dramatic punch you could want. A tiny bit of sunlight will strangely hit a small piece of the Moon. Yet wait till you see it. It’ll look like a brightly lit polar cap on an otherwise red sphere. Very cool and Mars-like. Set the alarm for 4 and it’ll look weirdly worthwhile, guaranteed, and there’s nothing that a true complete totality could possibly add.
But say you read this after that event. Then still consider one worthy full Moon oddity. You’d think it would be twice as bright as a half Moon, right? But it’s actually ten times brighter. Even so, the full Moon is far less brilliant than we recall. Go ahead, ask your friends or family: Away from artificial lights, how many times brighter is a sunlit scene than the same vista viewed in full Moonlight? People always guess somewhere between 100 and 1,000, meaning the public think the Sun is at most a thousand times brighter than a full Moon.
The real answer: The Sun is 450,000 times brighter. It’s no contest at all.
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