On Halloween, the sky will be lit up by a rare blue moon on the spookiest night of the year!
While it is called a blue moon, the moon won't actually appear blue. The phrase refers to the time when a second full moon occurs in one month.
According to NASA, a blue moon occurs about seven times every 19 years.
This year, there will be a full moon on Oct. 1 and on Oct. 31.
The last blue moon appeared March 31, 2018, according to Earth Sky.
