Rare Blue Moon this Halloween - Aidan Mahoney

Halloween's Blue Moon

This October 31 will feature a rare sight during the night. Not only will there be a full moon this halloween but one that hasn't been seen then since World War II! A Halloween blue moon. Jeffrey Hunt, an astronomy educator, says “The last Halloween full moon visible around the globe came in 1944.” This year's full moon will be seen in all parts of the world. One of the best parts, the blue moon will be so bright that you won’t need any equipment to see and it will shine brightly no matter your area. Just a regular full moon on halloween only occurs once nearly every 19 years. 

A Greek mathematician, Meton of Athens, had discovered this lunar cycle in 432 BC. He had predicted the phases of the Moon would repeat on the same date after 19 years had passed. Meaning that a full moon would be seen on the same day 19 years apart. This was known as the Metonic Cycle. Unfortunately it isn't entirely true. Because of variations in the moon's orbit and the leap days that intervene over 19 years, Menton's theory is rarely accurate. It can still be accurate however depending on the year and what changes occur. 

The Metonic Cycle worked well in 1925 to 1944. After that, the full moon’s 19 year date prediction shifted to November 1st. In 2020 however the date now has shifted back to October 31st. This makes it even more rare of a sight. 

This Blue Moon will occur at about 10:49 eastern time. Enjoy!