M27 – The Dumbbell Nebula

M27 is located in the constellation Vulpecula and lies at about a distance of 1300 light years from Earth. It was the first planetary nebula discovered by Charles Messier in 1764 while he was compiling his list of objects that, to him, looked like comets. The dumbbell nebula has a visual magnitude of 7.5 with a diameter of 8 arcminutes. Easily spotted in binoculars and small telescopes, and starts to show more detail in larger scopes.

‘X’ Marks the spot of M27

William Herschel named these “Planetary Nebula” because the green tint surrounding them reminded him of his discovery of the planet Uranus. He guessed that this was a newly forming solar system, but as we know now it is the result of a moderate to small star when it reaches old age. After a star uses up all it’s hydrogen the cores shrink, heat up, and they start to burn helium. After the core collapses into a white dwarf star, the outer parts expand into space and form a shell.

My Observation: The few planetary nebula I have seen have definitely made them one of my favorite deep space objects. Once centered in with my telescope at a magnification of 30x this planetary nebula is very prominent and stands out quite bright against it’s dark star filled background. At this magnification I didn’t notice the central white dwarf star, but I could make out the apparent ‘dumbbell’ shape which it got it’s nickname from.

M27 – The Dumbbell Nebula

M27 – Dumbbell Nebula. This is a re-edit of the same data used in the above image.

This image is a stack of 41 images at 30 seconds a piece and ISO800. Stacked in deep sky stacker, and edited and composited in Gimp. I did two different edits and layer masked them to bring out the red and the green colors. Taken with a Canon 350D prime focus through my Omni XLT 150.

August 4th, 2011 Viewing Session – M27 and Coathanger Asterism

I went onto my back porch to do my viewing last night (all my observations were made on the 5th of August) because the two objects I was after were clearly visible even with the tree cover I have in my yard. I was after M27 – The Dumbbell Nebula, and I was after the asterism known as Brocchi’s Cluster, or Coat-hanger Asterism.

M27 – Dumbbell Nebula is a Planetary Nebula (magnitude 8.10) in the constellation Vulpecula which is latin for “little fox”. Vulpecula is very close to the constellation Cygnus, and just below it is the constellation Sagitta which is latin for “arrow”. I spent quite a bit of time looking for the Dumbbell Nebula because for some reason I couldn’t pinpoint it even with the help of Stellarium, and The Pocket Sky Atlas from Sky & Telescope. Once I finally found it I attempted to take a few pictures, then it dawned on me; I should get into trying to sketch objects I see. I found sketching to be a great way to study the detail of an object, and to spend quite a bit of time with it. The more time you spend looking at something the more you start to see. Also after sketching I wrote a few notes to help remember what I saw. My eye was wandering all over the eyepiece looking at all the stars. Some stars were only visible with averted vision while other were quite bright and easily seen looking directly at them. I used both my 32mm eyepiece giving me a magnification of 31.25, and the 12.5mm eyepiece giving me a magnification of 80. In both magnifications the nebula is very faint and fuzzy, although it seemed to me just as bright, if not a tad bit brighter in the 12.5mm surprisingly. Usually the higher the magnification the dimmer an object gets. I could just barely make out a dumbbell shape in the nebula through both eyepieces, detail was a bit better in the 12.5mm. While sketching and viewing I saw what I’m going to call space junk flying through my view through the eyepiece. It could have been a satellite but it was very dim and couldn’t see it with the naked eye, and stellarium didn’t show any satellites in the area at the time (12:45am Aug. 5th). With both eyepieces I wasn’t able to make out any color, which is normal when viewing. Color usually starts to show with long exposure photography or very very dark viewing areas that lack light pollution. I also noticed and took note that with the 12.5mm eyepiece the nebula seemed to almost “pop out” and appeared closer than the background stars in the field of view.

Photograph is 6 pictures stacked. ISO400 F3.1 30sec exposures.

Next was Brocchi’s Cluster/Coat-hanger Asterism which is an average of around a magnitude 6. Also in the constellation Vulpecula, but very close to Sagitta. With the naked eye from my back porch it looked like a very small fain cloudy/fuzzy light. I almost couldn’t see it, again averted vision was key in spotting it. I only used my 32mm eyepiece which just fit the entire thing into my view. No sense in using a higher magnification if I’m just going to see less of the object I’m looking at. The more I’m into astronomy the more I realize how important a good low power eyepiece truly is. In the cluster I was able to make out around 27 stars clearly, although a couple were only visible with averted vision (if you haven’t noticed averted vision helps A LOT when viewing). Of the 27 stars that I saw there were around 10 of the brightest ones that made up the coat-hanger shape. There is no nebulosity to this asterism it’s just a nice little open cluster of stars that happen to look like a coat-hanger just floating overhead.

I ended the night watching the ISS pass at 2:40am and was tempted to bring the scope back outside to look for Andromeda again since it was high up in the sky, but I was too tired and decided it can wait until it rises earlier or until next time if I can stay up late enough to view it. Another great night in the Adirondacks with great viewing.