Noticeable solar rotation

[Stu]

Just a quick one, didn't know what title to use!

Yesterday I had the scope out all day, observing in white light. I spent a little time viewing first thing, then the odd 5 minutes during the day right through until the sun was very low and down in the haze.

Because the AR was so close to the limb, it was easy to see the change from morning until evening; I was viewing the AR from more and more acute angles as it approached the limb. It was interesting to be able to notice this effect due to the sun's rotation. I've seen it once or twice before but as said, it is most noticeable when there is a good sized AR near the limb.

@Moonshane did you get a chance to sketch in the evening to compare with the morning?

[Moonshane]

Hi buddy 

I see the effect you described but had no time for sketching unfortunately.  I agree it's noticeable especially with the big ARs 

[Owmuchonomy]

I ran a BBQ brunch for my cycling mates and set up both the Lunt 60 and my ED80 in WL.  One of the guys remarked how he could detect rotation by periodically checking the position of AR next to the limb.  I guess he was there about 4 hours or so.  More noticeable was the sharp prom in Ha associated with the AR.  The AZ EQ6 GT in AZ mode is so great for these parallel viewing sessions.

 

[Stu]

That looks like a perfect way to spend a few hours