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Can anyone help with this question about stars ionizing the Lion nebulae SH2-132? SOLVED

OIII Off-topic Emission Nebula
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Tim Hawkes avatar
Tim Hawkes avatar
I recently imaged the Lion nebula and was intrigued by an apparent straight beam of O3 ionisation near the core   https://www.astrobin.com/y3uet3/  .  Others have commented on this and ascribed it to part of a ring nebula around the star WR 153 as referenced for example  here https://www.astrobin.com/383587/
That seems a reasonable explanation.  Strong stellar winds from a WR star pushing out a perimeter of ionised material including O2+ which appears straight in some regions ?  cf also https://arxiv.org/abs/1002.4612


However I have also seen a number of references putting the  distance of the Lion nebula out at > ~ 10,000 light years but the Hipparcos distance of HD211853 (aka WR 153) at only ~ 1400 ly   https://www.universeguide.com/star/110154/hip110154

However the data in Stellarium database put it at 15500 light years?

Have I just got something wrong here and does anyone know more about this topic?

I don't know which estimate is wrong -- the star distance or the nebula distance but they seem quite inconsistent?


POST-SCRIPT  Solved this one now.  This link to a WR star database http://pacrowther.staff.shef.ac.uk/WRcat/  puts the distance to WR153 at 4.06 kpsc so my original reference for the WR153 distance had a typo in the data.    Both  WR star and nebula are  very distant at ~ 15000 ly 

thanks
Tim
Rouz Astro avatar
Rouz Astro avatar
Interesting question, I recent saw it in an image with my CDK14 as well. Someone commented that it's a processing artifact but I'm sure its not.


https://www.astrobin.com/55f2yb/C/

Tim Hawkes avatar
Tim Hawkes avatar
Thanks for the image.  Very nice.  I agree. Definitely not an artifact, looks oddly linear and others have commented on it too.  Wolf Rayet stars, their stellar winds and the energetic expanding OIII- bright nebulae that they produce are a fascinating area - that as far as I can gather is not that well understood or studied.  It is certainly not obvious (to me anyway) in this case quite how the linear OIII region would be geometrically related to WR153ab?   Of course the Lion is a rich object for WR nebulae with the WR star and predominantly blue around the tail also. Currently I am working on bigger images to try and capture both ends as a first for me.