'Tis a true Harvest Moon

If you've been outside the last two nights you probably noticed the harvest of moonlight casting a silvery glow on the browning foliage.

As bright as it has been, the moon is about to pick it up a notch, and for the first time in 20 years it will become full on the first full day of autumn.

It should rise through the clouds brilliantly in the eastern sky at 6:20 this evening, or 28 minutes before sunset. So for awhile, at least, if the clouds cooperate the first moonlight and solar twilight will overlap.

The moon will reach 100 percent fullness at 5:18 a.m., or just over six hours after the arrival of the astronomical fall. At the equinoctial moment, 11:09 p.m., Jupiter will be right beside the moon. 

The forecast calls for a chance of showers, but the skies should break at times. Among night-sky phenomena, a personal favorite is watching the moon electrify the edges of the racing clouds that it is trying to escape.

This is the so-called harvest moon, the one that occurs closest to the equinox. It takes its name from pre-electricity agrarian days when farmers exploited moonlight to extend the working day at a time when precious daylight was slipping away.

Here's more on the harvest moon from NASA.