2020: Most Full Moons In A Year?

Even though the COVID 19 pandemic has reduced amateur astronomy into a much lonelier endeavor, will this year’s surfeit of full moons be a consolation - and a special time - to amateur astronomers?

By: Ringo Bones

The global astronomical community announced back in January that 2020 will be a very interesting year for amateur astronomers and stargazers the world over because it will have 13 full moons instead of the regular 12. And October 2020 will be special because it is when two full moons will occur in the same month, not to mention another rare astronomical event is set to happen this month – a 100-percent full moon falling on Halloween night.

October 2020 will prove to be of interest to amateur astronomers and stargazers around the word because it will be a “full moon event” – i.e. two full moons occurring on the same month. For more than half a century, if two full moons fall on the same month, it is dubbed as a blue moon. Ideally, a blue moon event happens once every two and a half to three years. The October 1^st full moon of 2020 was dubbed as a “Harvest Moon” as such events have been called since antiquity, and the Halloween Full Moon of 2020 that will occur on October 31^st will be dubbed as a “Hunter’s Moon” – i.e. the full moon that occurs after a Harvest Moon.

Even though artistic depictions of Halloween night – more often than not – had always shown a full moon high in the sky with kids in various Halloween costumes trick or treating the night away, a full moon occurring on a Halloween night is actually a relatively rare event. The last time that Halloween night was illuminated by a 100-percent full moon was back in 1944.

Ideally, a 100-percent full moon on Halloween is supposed to happen once every 19 years, but given that the 31^st of October falls on a different day of the week year after year, a full moon on Halloween is a very rare event indeed. According to astronomers, the next time a 100-percent full moon will be shining on a Halloween evening after 2020 will occur in the year 2039, then in 2058, then in 2077 and the last one for the 21^st Century will occur in 2096.

The good news is that even if a scheduled 100-percent full moon event will fall a day or two before or after the October 31^st Halloween night, it can still serve as a spooky Halloween night backdrop because since most people, and most general-purpose hand-held cameras, can’t tell the difference between a 100-percent full moon and a “mere” 98-percent full moon. Because of this, October 31, 2031 Halloween night will seem to appear just as spooky to future Halloween revelers as this coming October 31, 2020 Halloween Night.