A cloud-striped full moon makes a reflection on Lake Superior in Duluth last month (Aug. 14). Bob King
Fall sneaks in at 2:50 a.m. (Central Time) on Monday September 23. We’ll literally wake up to a new season that morning. But before that happens, watch for the Harvest Moon this Friday night September 13. The big yellow moon will rise around sunset and shine all night. The Harvest Moon is the full moon that occurs closest to the autumnal equinox or first day of fall. Often that happens in September, but occasionally in early October.
What makes the Harvest Moon special is that it rises at nearly the same time several nights in a row. Normally, the moon rises about 50 minutes later and moves about a fist east each night, but during the Harvest Moon successive moonrises are only about 20-25 minutes apart! This can make it seem like we’re getting one full moon after another.
The angle of the Moon’s path to the horizon makes a big difference in moonrise times. At full moon in September, the Moon’s path is nearly parallel to the horizon, so successive moonrises are just 20+ minutes apart. At full phase in spring, ...