The last time a full moon occurred on Friday the 13th was June 13th 2014. It won't happen again until August 13th 2049.
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MOIYA MCTIER,
Astrophysicist, Folklorist, & Science Communicator
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Full moons happen roughly every 28 days. That number is fixed.
But Friday the 13ths happen roughly every 200ish days, and that number varies because months have different lengths and start on different days of the week.
SO just the way those two cycles work together means that sometimes they'll line up twice in five years, and other times it won't happen for several decades.
I'm trying to do the math in my head and getting lost. There are 12 chances for Friday the 13th's in a year I guess, and given the months are specific lengths I guess there's 7 different patterns of Friday the 13th's depending on whether Jan. 1 is a mon, tues, wed. etc. So that you crunch it out, but then what's the period of a moon cycle? And mostly how could this happen twice in 5 years and then not for 30?