Photography

https://www.democraticunderground.com/1036129000

I took some pics today, but they weren't very good because of scattered light clouds. However, I got good enough images to compare the spots to yesterday, and it occurred to me that I could use them to estimate the sun's rotational period. I took the pixel width of the sun along the line the spots traveled as a diameter to estimate a circumference. I then measured the pixel distance the spots traveled and added 1/365th of the circumference to account for the Earth's movement in its orbit, then divided that into the presumed circumference. I got about 27 days. I then looked up the actual answer, and it turns out that since the sun is a ball of gas, the gas at the equator rotates faster than the gas near the poles. At the equator, it's 25 days, tapering off to over 30 days near the poles. The big spots appear to be somewhat south of the equator (we're seeing more of the south pole this time of year), so I'm pretty happy with my estimate.