The Sun's Disk Seeming to Spin Slowly Clockwise as It Moves Across the Sky
Everyone knows that the Sun isn't really moving from east to west every day; it just looks like it is because of the rotation of the Earth. What's less commonly realized is that the orientation of the disk of the Sun seems to spin slowly from sunrise to sunset. Since the Sun basically looks like a solid-color circle, it's hard to tell this by looking at it normally. But by observing sunspots during the course of a day, you can see that the Sun's apparent orientation is changing.
These five photographs were all taken on the same day with a level camera. The approximate position of the Sun's north pole in each photo is indicated by a red arrow. (The times are Pacific Daylight Time.)
