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Harvest moon tonight -- take a look

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Harvest moon tonight -- take a look

September 12, 2011 | 5:52 pm

Thank goodness for the harvest moon.

In a lot of ways, September is a bummer: Summer is all but officially over, school is just starting, and everyone is returning to what feels like real life. But then you'll be driving home from work or glancing out the window while doing dishes and notice a big, fat, low-hanging moon floating in the twilight. That's the harvest moon -- Mother Nature's annual consolation prize for taking summer away from you.

Steve Edberg, an astronomer at the Jet Propulsion Laboratory, explained that because of the tilt of the moon's orbit in September, the moon rises just as the sun is setting for a few days after the full moon. Usually the moon rises at sunset only on the day it is full and then rises about an hour later each subsequent day.

"There's nothing really special about it. I's just that people are more likely to notice it because it has this effect that looks like it hasn't really changed positions, and it seems like it is hanging around a lot longer," he said.

This might have mattered to people in agrarian societies, because for several days in September they could continue to work in the field by moonlight even after the sun had set. Hence, the name "harvest moon."

You may notice that the moon seems to be extra large this time of year, but Edberg said that's just a trick of the eye called a "moon illusion."

When the moon is lower in the sky, our brains seem to read it as looking bigger. Theories abound as to why, but Edberg said there is no consensus. In fact, said Edberg, a moon directly overhead is technically 4,000 miles closer to us because of the way the earth curves.

The full moon was Sunday night, so the harvest moon will continue to rise just around sunset for a few more days.

Take a look tonight and enjoy.

 


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