Friday’s blue moon will be the last time people get the chance to see the lunar event for three years, but even people living under cloudy skies or who can’t get outside will have a chance to view it.
A word of warning, the New York Daily News writes — don’t expect to see any color change with the moon. Despite the name blue moon, the lunar event actually marks the second time there will be a full moon in the month of August. Full moons occur every 29 days, so when the calendar matches up correctly nocturnal observers get the chance to see a “blue moon.”
The modern definition of blue moon only dates back a few decades. It originally meant the third full moon of a season with four full moons, but in 1946, an amateur astronomer named James Pruett misinterpreted the phrase in the Maine Farmers’ Almanac to mean the second full moon of the month.
He popularized his mistake when he wrote an article for Sky Telescope magazine titled “Once in a Blue Moon.” From there the incorrect definition became the common usage, Space.com reported.
The Slooh Space Camera broadcast of the blue moon will honor another lunar legend, astronaut Neil Armstrong. His funeral is coincidentally the same day, TIME reported. It’s apparently the kind of coincidence that happens once in a blue moon.