The Harvest Moon is the full moon closest to the autumnal equinox. The equinox is when the length of day and the length of night are equal all over the earth, 12 hours each. The equinox was last night; the full moon is tonight. This moon is called the Harvest Moon or the Hunter’s Moon because there is no period of darkness between the setting of the sun and the rising of the moon. In fact, tonight in Chicago, the sun set at 7:14pm and the moon rose before the sunset at 6:31pm. (OK, OK, I know, it’s an earth turn…) In other words, the farmers (and hunters) could continue working into the night with enough light to bring in the harvest.
Also there was an alignment of Jupiter (visible by eye) and Uranus. On the 21st, Jupiter was in opposition meaning that it was exactly opposite the sun. On the 20th it was the closest it has ever been to earth in 50 years—a mere 368 million miles away. This morning at 1am, Uranus was in opposition (visible by telescope), ie exactly opposite the sun.
Today at 3pm Jupiter and Uranus were in conjunction (less than 1 degree apart) but not really that close, only apparently so. Full moon tonight means that the moon is in opposition to the sun.
Tonight we went to the lake to catch the Harvest Moon rise. Though it was overcast, the moon did peer out for a few moments (see below). And we weren’t the only ones there for the dramatic entrance. Everyone had a front row seat.