New England Gets Rare Halloween Blue Moon

MASSACHUSETTS — The rare Halloween blue moon Saturday offers a great way for people across New England to celebrate in a way that is fitting with the holiday and may help relieve a little stress: At moonrise, step outside and howl.

The moon should be visible above buildings or trees a little after 6 p.m. tonight.

Start with some yelps. Then let loose with a full-voiced howl that will pierce the night air. This is actually a thing that has been happening across the U.S.

Moon-howling in the United States has emerged as a way to thank health care workers and other first responders. It's also just a way to blow off the stress of being cooped up. At the annual Burning Man event in Black Rock desert of Nevada, it's just a way to welcome the night and cooler weather. On Halloween, it's just fitting.

So what's a blue moon? Every month has a full moon, but the lunar cycle and calendar aren't perfectly synced. They happen every 29.5 days when the moon is on the opposite side of the Earth and its face is fully illuminated by the sun. When there's a second full moon during the same month — as is happening in October — it is called a blue moon.

Ironically, it has nothing to do with the color of the moon. You've no doubt heard the phrase "once in a blue moon," which means something that doesn't happen very often.

A blue moon on Halloween is especially rare.

The last time there was a Halloween blue moon visible across the United States was in 1944, and it won't happen again until 2039, according to the Farmers' Almanac.

It isn't categorized as a supermoon, but as with the Oct. 1 full harvest moon, the Halloween blue hunter's moon may seem more orange and larger over the horizon than other full moons.

The Old Farmer's Almanac explains why. A moon illusion, "when the moon is low, it is viewed in relation to earthly objects, such as chimneys and trees, whose size and shape provide scale."

The brain makes comparisons of the moon on the size of the other objects the eye sees, "and suddenly, the moon looks massive," the Old Farmer's Almanac says.

Coming after the harvest moon, this year's Halloween blue moon is known as a hunter’s moon because the moonlight helped hunters preparing for winter to see deer and other game animals in recently cleared fields.

It is sometimes referred to as the sanguine or blood moon, perhaps because of the blood associated with hunting, the Old Farmer’s Almanac says, but also possibly because it is associated with the brilliant colors of fall foliage.

Some other names for non-harvest October full moons are the "travel moon" or the "dying grass moon.'

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The light from the Halloween blue moon will interfere with watching for shooting stars from the Taurid meteor shower. The shower runs annually from Sept 7 to Dec. 10, peaking around Nov. 4-5. After midnight will be the best time to look for meteors, which radiate from the constellation Taurus.