>Hello all: I just looked at the SOHO solar satellite photos of the sunspots and noticed that the spots were different from the ones I saw on Christmas morning. Could it be that SOHO was on the opposite side of the sun when the picture was taken? Or maybe the sun's rotation since Christmass brought the sun's farside into view.
If an earthboud observer wants to see both sides of the sun, how long will he have to wait between observations until the sun rotates 180 degrees? What is the rotation rate of the sun? John Carmichael Tucson Arizona p.s. I forgot to mention that during the partial solar eclipse, using the telescope solar image projection, we could see valleys and mountains on the edge of the moon that was in front of the sun! The diameter of the sun's image was about 30 cms. > >We watched the Christmas partial eclipse using a telescope to project an >image of the sun onto a white piece of stiff paper. I fitted the large end >my 4" refractor with an 18" square piece of cardboard with a 4" hole cut >into it so that the cardboard would shade the viewing screen at the other >end from unwanted sunlight. > >Even more amazing than the eclipse were the large number of sunspots. I've >never seen so many. We counted 24 of them! This is because the sun is at >the peak of its 11 year solar cycle. I checked, and found out that the sun >will be at perihelion on January 4. I wonder if the closeness of the earth >to the sun at this time of year will make the sun's disk appear larger and >therefore permit closer inspection of the sunspots, or if the increase in >size of the sun is too small to be significant. > >Does anybody know the difference in the apparent diameter of the sun, in >degrees, between perihelion and aphelion? Is this significant? > >Thanks > >John Carmichael >Tucson Arizona > >p.s. Some of the sunspots are so large that they can be viewed without a >telescope with the eye, using a welders smoked glass. > >
