Solar

Ionize Calcium / Better Than H-alpha?

This post (http://spaceweathergallery.com/indiv_upload.php?upload_id=148025&PHPSESSID=ufu9aq45u6ht3gl4rhuesc8jj2)

is entitled “Ionize Calcium / Better Than H-alpha?”

Not sure I’m convinced!

Compare with this a day earlier –  http://spaceweathergallery.com/indiv_upload.php?upload_id=147977&PHPSESSID=ufu9aq45u6ht3gl4rhuesc8jj2

(same as this: https://roslistonastronomy.uk/nice-prominences-this-morning-13-09-2018)

Need to see Ha and Ca-K at the same time. Pete? Andy?

Interestingly, although we have no sunspots, prominences are fairly abundant.