September 28, 2013

NGC 7635, the Bubble Nebula (Sept. 24, 2013)


OK, I've shot this before, but I needed a target after M27 set and before my next target came up.  Here it is.  This is the Bubble Nebula, or NGC 7635, in Cassiopeia.  It is a strange and wonderful object.  A very large, bright star is blasting the bubble out of a cloud of gas.  The star sits in what appears to be the upper right of the bubble.  Just below it is a knot of gas that the star is slowly blowing away with ultraviolet radiation.  The head of the knot glows like a star because it absorbs so much energy.  All the glowing gas you see here is ionized hydrogen and nitrogen, as the filter I used catches only those two.  The gas is glowing from radiation emanating from the same star.  It's such a dramatic scene!

Telescope: Astro-Tech AT111EDT and William Optics AFR-IV (eff. at f/5.6)
Camera and Exposure: SXVF-H9 (Ha-NII: 7x1200"), Alnitak Flat-man flats
Filter: Astronomik Ha-NII
Guiding: SX Lodestar and SX OAG
Mount: Takahashi NJP
Software: Nebulosity, Maxim DL, Photoshop CS3
Location: The Woodlands, TX

Dumbbell Nebula, M27, in OIII (Sept. 24, 2013)


Finally, clear skies again.  I took a few images of M27 through an OIII filter in June and have wanted to go back to it.  This nebula is so dramatic in the light of ionized oxygen!  In fact, this nebula is quite a sight no matter how you look at it.  This summer while observing the excellent skies near Bear Lake, Utah, I glimpsed M27 in a low-power eyepiece through my SV80ED.  The nebula looked like a cotton ball, round and puffy, floating in the Milky Way!  M27 lies roughly 1,300 lights years distant in the constellation Vulpecula.

Telescope: Astro-Tech AT111EDT and William Optics AFR-IV (eff. at f/5.6)
Camera and Exposure: SXVF-H9 (OIII: 9x1200"), Alnitak Flat-man flats
Filter: Astronomik OIII
Guiding: SX Lodestar and SX OAG
Mount: Takahashi NJP
Software: Nebulosity, Maxim DL, Photoshop CS3
Location: The Woodlands, TX