› Forums › Sun › Do sunspots have a “proper motion”? › Sunspots
28 July 2021 at 11:25 am
#584531
Steve Holmes
Participant
Thanks for the link to that Bulletin – very interesting (though I would note that the last bit should be “WeeklyPDF” rather than “Weekly/PDF”). However, it shows that whereas 2836 does indeed move from 57 to 62 degrees, 2835 also moves – if a little less. This might be a reflection of the changing shape of the entire 2835 group though (and hence a shift of its “centre of gravity”) rather than proper motion as such. The situation with 2836 is much more clear-cut though so I think we can say it truly does exhibit proper motion. Just my luck to choose to follow a small spot on the basis that it would be easier to measure!