I've always wanted to get closer to the cluster at the center of this nebula. A clear night this week presented an opportunity. I had some trouble with the 254mm Orion Newtonian early on: a poorly installed dew heater was warping the secondary. When I realized what the problem was and shut off the dew heater, the field quickly flattened out. By that time, NGC 281 was just coming over the trees. This is my first image of the nebula with the big Newt, and the first time I've shot H-alpha through the big scope. I don't think it will be the last time. This is also first light since installing a
Protostar tubeliner inside the scope.
NGC 281 and the open cluster in the center of the image, IC 1590, are about 9,500 light years away. The nebula is bright because the stars in it are bright. The nebula is an emission nebula, which means that the gas of the nebula (hydrogen in this image) is excited by the ultraviolet light of the stars in the cluster. The cluster and nebula are a package deal.
What I like about this nebula in particular are the clumps of gas and dust in front of it. The clumps are being worn away by starlight, but several of them stand out against the face of the cloud, including the long river near the cluster and several little globules in the upper right.
It's a grand sight! I recommend clicking on the full resolution link above, toggling F11, and panning about.
Telescope: Orion 254mm f/4.7 Newtonian and Astro-Tech Coma Corrector (eff. at f/5.17)
Camera and Exposure: SXVF-H9 (1x900" + 12x1200"), T-shirt flats
Filter: Astronomik 12nm Ha
Guiding: SX Lodestar and SX OAG
Mount: Takahashi NJP
Software: Nebulosity, Maxim DL, Photoshop CS3
Location: The Woodlands, TX