Space – Look for the Harvest Moon all week :: WRAL.com
Each of the 12-13 full Moons throughout the year has a name, often several. Many have their roots in Native American names and reflect what tribes were doing at the time hunting, fishing, and with their crops. According to folklore, the Harvest Moon gets its name from the light it provided farmers to bring in their crops into the early evening as days grow shorter.
But that is true of any full Moon, which rise around sunset and shine brightly until sunrise. What sets the Harvest Moon (Monday 7:30pm) apart is that it is the full Moon occurring closest to the September Equinox (Wednesday, 2:41pm ET).
The Moon, like the Sun, takes its lowest path through the sky around this time of year. Unlike other times of the year where the Moon rises an average of 45-60 minutes later each evening, the Moon will rise 26-30 minutes later each evening.
That may not seem like a lot, but the brightness of the full, or nearly full, Moon rising so soon after sunset, never lets the sky to get really dark. So, work can continue, at least that’s how the story goes.
2021’s Harvest Moon is the closest to the equinox since 1980. It wont be closer until 2029 when the full Moon and Equinox will be separated by just over an hour.
Big bright Moon this week
You may also notice the Moon seems a bit bigger this week for an hour or so after moonrise. The reason for this is also seasonal, and also because of how our brains work.
The Moon appears bigger to us near the horizon because of the Moon illusion. Scientists are divided on exactly what causes this, but there’s general consensus that it is because of how our brains process the information our eyes are sending. One explanation is that, while near the horizon, we’ve got familiar objects like trees and buildings to compare the Moon with, so it looks huge.
NASA astronauts disagree with this explanation saying that they’ve also experienced the Moon illusion from space, with nothing in the foreground to compare the Moon too. The Moon still looks bigger to them.
The Moon will also look a yellow-orange color as it rises, this is normal as the moonlight passes through more atmosphere near the horizon, scattering more of the blue light and lettering more red light through. Smoke from wildfires on the west coast also enhance this effect making the Moon look even more red.