March 3, 1876, was a cloudless day in Olympia Springs, Kentucky. Late that morning, a resident named Rebecca Crouch was out in her yard making soap when a strange kind of snow began to fall. At least, that’s how she described some of the pieces drifting down: about the size of snowflakes, only they weren’t white. They were red, and they looked like meat — beef, she thought. 

According to a New York Times report shortly afterward, “Mr. Harrison Gill, whose veracity is unquestionable … visited the locality the next day, and says he saw particles of meat sticking to the fences and scattered over the ground.” The paper also noted that “two gentlemen, who tasted the meat, express the opinion that it was either mutton or venison.”

The first scientific analysis came three months later, when a water treatment specialist named Leopold Brandeis examined specimens preserved in glycerine. He declared that “the Kentucky ‘wonder’ is no more or less than nostoc.” Nostoc — also known as star jelly or witch’s butter — is a type of cyanobacteria that swells into green, jellylike masses after a rain. But the theory had problems: The mystery material wasn’t green, and it hadn’t been raining, and it didn’t explain why it looked and tasted like meat. 

While the circumstances remain mysterious, the leading scientific theory today is that the Kentucky meat shower was the result of projectile vulture vomit. Vultures are common in Kentucky and are known to disgorge their stomach contents when spooked. 

Writing in an 1876 edition of the Louisville Medical News, chemist L.D. Kastenbine explained: “The only plausible theory explanatory of this anomalous shower appears to me to be … the disgorgement of some vultures that were sailing over the spot, and from their immense height, the particles were scattered by the then prevailing wind over the ground. The variety of tissue discovered — muscular, connective, fatty, structureless, etc. — can be explained only by this theory.”

Whatever really fell from the Kentucky sky that day, the event now sits firmly in the canon of classic weird facts. It’s been celebrated in books and podcasts, and even marked with a festival featuring a mystery meat chili cook-off.