If you asked people to name one full Moon, the top vote-getter probably would be the one that lights up the sky tonight: the Harvest Moon — the full Moon that’s closest to the start of autumn.

For most of the modern world, the Harvest Moon is little more than a bit of folklore. But in the days before automation and electric lights, it was a big help to farmers, who could work their fields well into the night.

And that’s not just because of the Moon’s brightness. It’s also because the Moon rises close to the same time for a few nights around the Harvest Moon — around sunset.

The effect is more pronounced as you go farther north. From states like Minnesota and Washington, the Moon will rise only about 15 or 20 minutes later tomorrow night than it will tonight. That’s compared to an average of almost 50 minutes later over the course of a year. At such high latitudes, where the frost comes early, every hour of harvesting could make a difference.

Perhaps because of its big reputation, many people think the Harvest Moon looks bigger than other full Moons. But that’s not the case. The Moon’s apparent size depends on its distance, which can vary by about 10 percent. The distance isn’t related to the Moon’s phases. So sometimes the Harvest Moon occurs when the Moon is closer than average, but other times it comes when the Moon is farther than average. Either way, it’s always fun to stroll beneath a beautiful Harvest Moon.
 

Script by Damond Benningfield

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