Free Republic

Explanation: How does your favorite planet spin? Does it spin rapidly around a nearly vertical axis, or horizontally, or backwards? The featured video animates NASA images of all eight planets in our Solar System to show them spinning side-by-side for an easy comparison. In the time-lapse video, a day on Earth -- one Earth rotation -- takes just a few seconds. Jupiter rotates the fastest, while Venus spins not only the slowest (can you see it?), but backwards. The inner rocky planets across the top underwent dramatic spin-altering collisions during the early days of the Solar System. Why planets spin...

With unseasonably warm summer temperatures persisting over much of the world this year, it seems hard to believe that this is the week of the Harvest Moon, the full moon nearest to the autumnal equinox. Saturday, Sept. 22, was the first official day of autumn in much of the Northern Hemisphere, even though it will still officially be summer through the daylight hours. The moment of the equinox — the official end of summer and beginning of autumn — will not arrive until 9:54 p.m. EDT. East of the prime meridian, where the equinox occurs after midnight, the first day...