The northern hemisphere will be aglow in moonlight on the evening of Oct. 5, and not just any moonlight — harvest moonlight. That's right: This year, the Harvest Moon is occurring on Oct. 5, and it's sure to be a beautiful sight in the night sky. However, you might be wondering why you remember the Harvest Moon occurring at a different time in 2016 — and whether or not the Harvest Moon is always in October.
So, the short answer is actually no — in fact, the Harvest Moon occurs in September way more than it occurs in October. The reason for this is that the Harvest Moon is always the full moon that falls closest to the autumnal equinox, an event that usually that happens in September according to Earthsky.org. The autumnal equinox, of course, happened on Friday, Sept. 22 — making Oct. 5's full moon the harvest moon because it is the closest full moon in the calendar. For some perspective: The last time a Harvest Moon occurred in October rather than September was Oct. 3, 2009.
So, as far as celestial events go, this Harvest Moon is actually occurring unusually late in the season. There's no reason to be alarmed though: it's science after all. According to the lunar cycle, which follows a pretty strict 28-day pattern as the moon orbits around the Earth, this year's October Harvest Moon is coming right on schedule.
"More often than not, the September full moon is the Northern Hemisphere’s Harvest Moon," EarthSky.org wrote. "The Harvest Moon is usually defined as the full moon closest to the autumn equinox, which, in the Northern Hemisphere, comes on or near September 22 each year." The next time you can expect to see the harvest moon occur in October is in 2020.
So what can you expect to see during Oct. 5's Harvest Moon? According to the Old Farmer's Almanac, “the full harvest moon rises at sunset, then will rise very near sunset for several nights in a row,” making it seem like there are “full moons multiple nights in a row.”
Another, perhaps even cooler effect — depending on where you're located— is the the moon could give off an orangey-reddish glow which occurs when the moon is spotted near the horizon. Which I mean, hello, so seasonally appropriate.
As the name harvest suggests, the harvest would traditionally mark the start of harvest season, the time during which farmers would gather their crops in preparation for winter. That still holds true in large part even today as harvest season is the busiest time for vineyards around the world, as winemakers are eager to cultivate their bounty and grapes are at their peak.
If you want to brush up on a little moon trivia, according to the Austin-based website Earthsky.org, there are tons of other moon names you may or may not be aware of — like December 2017’s full moon aka the Cold Moon, January 2018's full moon aka the Old Moon, February 2018’s full moon aka the Snow Moon, March 2018's full moon aka the Sap Moon, April 2018's full moon aka the Grass Moon, May 2018's full moon aka the Flower Moon, and so on. My personal favorite? The Strawberry Moon, which occurs in June. What a cute name, right?!
So, in the spirit of tonight's very special October harvest moon, I'll leave you with the eternal lyrics of Neil Young's classic song, "Harvest Moon": "Just like children sleeping/ We could dream this night away/ But there's a full moon risin'/ Let's go dancin' in the light/ We know where the music's playin'/ Let's go out and feel the night/ On this harvest moon."
Happy harvest moon, ya'll.