Something’s happening this Halloween that literally only comes once in a blue moon.
A blue moon will light up the skies this Halloween, adding another level of intrigue to the spookiest night of the year. Or, it’s just a good chance to fill the costume party-sized hole in your Instagram feed.
Either way, the full moon will be visible on Oct. 31. Here’s everything you need to know about the event, and how to see it.
What is a blue moon, exactly?
To be clear, a blue moon isn’t actually blue. It’s just a term we use to describe the rare occurrence when we get two full moons in the same calendar month.
We already got a Harvest Moon on Oct. 1-2, so this will mark the month’s second fully lit sky. That might sound pretty normal, but it actually happens a lot less than you’d think.
According to the Farmers’ Almanac, a blue moon occurs every two and a half to three years, but, due to some funky calendar changes over the decades, it hasn’t happened on Halloween since 1944. That makes this a truly once-in-a-generation phenomenon.
How to see the blue moon on Halloween
The moon will be at its brightest at 10:49 a.m. EST. So, if you’re in the U.S., your best bet is to catch it in that sky early Halloween morning. Maybe set an alarm for while it’s still dark out if you want to catch the view.
It’s probably worth the wake-up, considering Mars will also be visible in the sky during that time. So, you’ll get a heavy dose of red and white (again, not blue!) shining through the sky over the weekend.
When is the next blue moon?
Thankfully (or unfortunately, depending on how superstitious you are), we won’t have to wait 76 years for this to happen again. The next Halloween blue moon is set to arrive in 2039.
Still, that’s a pretty long time to wait for a photo op, so it’s probably best to go ahead and get your pictures in now.
Check out In The Know’s list of tips for vacationing amid the pandemic.
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