2020 was a wild year. We've had forest fires, a pandemic, a once-in-a-lifetime comet, and a near-miss with a very close asteroid, and the year has more to give! This October, a unique event will occur, lighting up Halloween's night sky with a rare blue moon. October will surprise us with two full moons thanks to the blue moon that happens approximately once every two and a half years, NASA says. About The Event Blue moons happen because the lunar cycle and the calendar year are not entirely in sync. Full moons happen every 29 days, and most months are 30 or 31 days. The last time a blue moon was seen in America was March 2018. The first full moon can be seen on October 1. This year it is called the Harvest moon, as it is the full moon closest to the autumn equinox. The second full moon will peak 10:49 a.m. ET on October 31, creating a spooky backdrop for an unusual Halloween. Farmer's Almanac says that the las Halloween full moon happened in 2001, but only in some central and pacific time zones. This year is the first time in this century when a Halloween full moon is visible in all time zones. The last time that happened was during World War II, in 1944. The moon is also called the HUnter's moon because it is the first moon after the harvest moon. It was probably named because people would go hunting during that time of the year in preparation for winter. Clarification Unfortunately, the moon won't actually appear blue. The phenomenon doesn't imply an actual change of the moon's color. However, wildfires can affect the moon's color, so you might observe a blu blue moon or a red-blue moon next month, according to the region you watch it from.