Significant smaller star in NGC 7635 - Bubble Nebula?

3 replies132 views
DanJunge avatar
Hi all. 

I was in the process of aligning old data with new data, when I noticed that a star had become noticeable smaller within the last year. I then tried to figure out if this was a variable star, though it seemed a bit drastic to me. My next guess was that somehow my data from last year was faulty. The new data is Luminance, so it should show the data in all wavelengths, therefore it could not explain the star being smaller. I didn't come any closer an answer... So...  

I got quite curious in what could do this. If it was something I missed. I know that there must be someone in here that have the answer, and I'm not afraid to embarrass myself in the search for an answer 

Most of all it could be fun to see if any of you have data showing the same?



Old data (April 2022)



New data (September 2023)

Engaging
Sean Mc avatar
To be honest, it looks like the newer data is just better.  All the stars look smaller.
Quinn Groessl avatar
I believe I have the right star here. https://simbad.cds.unistra.fr/simbad/sim-id?Ident=%40127405&Name=V*%20MP%20Cas&submit=submit

It looks like its a mira variable star. I'm not an expert by any means, but I think that explains the drastic difference.
DanJunge avatar
Thank you so much for your replies. 

That it's a variable star would make sense. Also as stated my first thought. It just seemed a bit drastic the difference, but then again, I don't know how much these stars can vary in size. 
Also your link is very helpfull. I didn't know where to search this information. Now I do. smile
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