Once in a “Boo” Moon 😮⁣ ⁣ Tonight, don’t forget to look up to the sky to see an eerily timed phenomenon, a Halloween Blue Moon! The last Blue Moon took place on March 31, 2018, and this is the first full moon on Halloween in 76 years.⁣ ⁣ The phrase “Blue Moon” is commonly used to describe the second full moon in a calendar month. Astronomical blue moons have a regular pattern and occur roughly once every two and a half years. Halloween falls on a full Moon once every nineteen years, on average. Since the Moon is full about once every 29.5 days, and October is 31 days long, all Halloween full moons are blue moons.⁣ ⁣ Image Credit: NASA/Bill Ingalls⁣ ⁣ #nasa #bluemoon #NASAHalloween