By Bruce McClure
EarthSky Communications
Friday, Sept. 4, 2009
All around the world tonight, a great big, round moon rises in the east around sunset, and sets in the west tomorrow around sunrise. More often than not, the September full moon wins the title of Harvest Moon in the northern hemisphere. But not this year.
The next equinox comes on Sept. 22. By common practice, the September equinox marks the beginning of autumn in the northern hemisphere, and the start of spring in the southern hemisphere. According to northern hemisphere sky lore, the Harvest Moon is the closest full moon to the autumn equinox. Usually, the Harvest Moon comes in September. But, in years where the October full moon occurs in early October, the October full moon can actually fall more closely to the autumn equinox than the September full moon does.
And so it is in 2009. The October full moon enjoys the Harvest Moon designation, because it comes 12 calendar days after the Sept. 22 equinox. Meanwhile, tonight’s moon isn’t the official Harvest Moon, although many will call it by that name.
Tonight’s September full moon –– which takes place 18 days before the equinox –– has other names. The September full moon goes by the name Fruit Moon, Corn Moon or Barley Moon. For the northern hemisphere, this September full moon is the last full moon of summer. For the southern hemisphere, it is the last full moon of the winter season.
Like any full moon, tonight’s moon lights up the nighttime from dusk until dawn. Like any full moon, tonight’s moon climbs highest in the sky around midnight. Watch it shine from dusk till dawn!
More online at www.EarthSky.org.