Here is a 16min. exposure of The Bubble Nebula with my new camera. The nebula is an H II ( H+ ) emission nebula in the constellation Cassiopeia. The "bubble" is illuminated by the stellar wind from the massive hot mag. 8.7 young star (Only 4 million years old), SAO 20575 with a mass of approximately 44 solar masses. As we can see, this bright star is obviously not in the bubble center because it has moved a lot since it created the expanding bubble.
It was discovered in November 1787 by William Herschel.

https://en.wikipedia.org/wiki/Bubble_Nebula

https://en.wikipedia.org/wiki/William_Herschel

Time: 22:50UT 2026-08-08 Filter & Exp. R(8x30) G(8x30) B(8x60)Sec
Tel: C14 @ f/6.6 Camera ASI 174 MM Mini Mono @ +17°C 0.52"/pix Paramount GT-1100S
Odd Trondal Obs.code 238 (Uranium). Oslo Norway