Halloween night marks a rare event – a blue moon.
A blue moon can occur either when you have two full moons in one month, like what we are experiencing this year on Halloween, or when you have four full moons in one year. The first full moon this month occurred on Oct. 1.
The last time a blue moon occurred on Halloween in all time zones was in 1944, and the next time we’ll see a full moon on Halloween will be in 2039, though it may not be considered a blue moon. Full moons are separated by 29 days, so while most months are 30 or 31 days, it’s possible to see two full moons in a single month, but it is still a rare event.
“Typically, you get one full moon a month, but because the cycle of the lunar phases can be shorter, you can get two full moons in a single month,” said Dr. Nicolas Pereyra, assistant professor in the UTRGV Department of Physics & Astronomy. “When this happens, you call the second full moon a blue moon, which is what’s happening at the end of this month.”
A prominent Halloween trope, the moon for centuries has been used as a beacon to help guide travelers across oceans and control the ebb and flow of the tides. Aside from the sun, the moon is the only other object in space that is highly visible to the naked eye, a nightlight for the sleeping world beneath.
While the full moon may not turn you into a werewolf, (unless you’ve been bitten, of course) there has been speculation that the moon can control people’s emotions and actions, since most living things on earth are composed mostly of water.
“There has been no confirmed connection with the moon phases affecting historic events,” Pereyra said. “But having said that, there are many people who believe or support the idea that we are directly affected in some way by these lunar phases, so that’s something we can’t discard either.”
Those who want to check out the blue moon for themselves need only turn their gazes upward at midnight – naturally. Pereyra said this will be when the full moon is at its brightest and most visible.
“Midnight is your best shot as you’ll be looking at the moon at its highest point,” he said. “that will be your sharpest, clearest view, and that’s when you’ll have the least atmosphere between you and the moon.”