X UMi

[Paul M]

Tonight is my first outing since April. It's taken a nearly full Moon at the top of the ecliptic to burn the clouds away!

So I'm rusrty!! I set up my RC 250 c/w 0.8x reducer/flattener. Many teething problems along the way, including working out why PHD2 was sulking. Then I remembered I hadn't polar aligned. Still it was within 3 deg of the pole

So I use the Drift Polar Alignment tool in PHD2. My guidescope is a Borg 60ED and ASI12O mini. I had no idea what field I was looking at but noticed a brightish "fuzzy" curious as to what it was, I took a screen  grab in the hope of plate solving it later:

You probably don't need my directions to the fuzzy, but just incase, its below right of the green box. The line and box are just clutter from the polar alignmnet tool.

The image did solve but I had to delve into Simbad to identify. And it aint no fuzzy. It is in fact X UMi, a Mira type variable:

https://simbad.cds.unistra.fr/simbad/sim-id?Ident=%40317174&Name=V* X UMi&submit=submit

It isn't a momentary abberation. I chased that thing all over the frame for some time getting aligned. It remained a distinct fizzy. The images I can find online don't seen to show any nebulosity in the area,

What's going on? Any ideas?

 

[RobertI]

I may be way off here, but I think many of the stars in the picture have a similar but much fainter and smaller ‘glow’ -  the only thing different about this star that I can see is that it is very red M class, but not sure why it would generate a significantly greater ‘glow’ than other stars in the frame? 

[Paul M]

Indeed, The guide scope could do with a focus tweak. But that aside, I have seen another "fuzzy" in my current guide frame while I'm imaging IC342. I've got a screen grab to see if I can solve that. Maybe another very red star?

Interestingly, X UMi must be near the max of its range 12.5 - 18.4.  I can measure that in ASTAP, later.