This
Astrobin Debut Object is a red hypergiant star located about 4000 light years away in the constellation of Canis Major at a declination of -26 degrees. And even though it usually hovers around magnitude 8.3, it's a variable star with a historic range from 6.5 to 9.6. The star is HD 58061.
Star HD 58061 is one of the largest and most luminous stars in our Milky Way. However, it's buried so deep inside an asymmetric circumstellar envelope (CSE) of its own making that the surface of the star cannot be seen nor imaged in visual wavelengths. This means that when one looks at this object in the night sky with the hope of viewing one of the largest stars in the Milky Way or to submit a magnitude estimate to the AAVSO, they truly are only seeing the brightest variable nebula known!
In order to capture this envelop, as well as the star field, I had to take multiple exposures. My usual LRGB sub exposure time of 2 minutes with this EdgeHD11 f/10 system blew out this bright star badly. The large image here has 30 second subs, which still resulted in oversaturating the star. Usually having oversaturated stars in parts of the image is OK, but here I wanted to try to capture the asymmetric CSE nebula shape. The inset image uses 10 second subs, which was finally short enough to be able to capture the asymmetric nature of the nebula surrounding the bright star.
The CSE has a diameter in my image of about 10 arc-seconds, which corresponds to an actual diameter of 0.2 light years. This diameter ranges widely in the literature - it is hard to distinctly measure the boundary of such a bright object.
Thank you to Scott Harrington for bringing this interesting tiny object to my attention, and for his help in writing this description.
Also thanks to
@Molly Wakeling for pointing out the brilliant song celebrating the star,
here. Good luck getting that song out of your head.
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