Friday, August 27, 2010

The Other Side of the Veil Nebula

Click on the image for a large view
As you read in my last post, the "Witches Broom" is one part of a very large supernova remnant.  To the east of the Witches Broom, 3 degrees away, is the other half of this beautiful complex of gas expelled from an exploded star.  The remaining pieces of the star formed a shell of material similar to a bubble.  Just like a bubble, we can see right through the middle.  The shock wave that created the shell is expanding the filamentary matter out, away from where the star was located.  Only along the edges of the shell, where we see it edge on, can we see the fine branches of seemingly intertwining nebulosity.  The colors come from the presence of oxygen, sulfer and hydrogen made to glow from the energy of starlight.

There is another part of this wonderful nebula in between these two images called Pickering's (Fleming's) Wisp.  It is much fainter, but I am hoping to photograph it during the next new moon phase in a week or so.

The beautiful, delicate lacework is a wonderful sight in large telescopes.  Since the nebula is so large, one has to move the telescope along the wispy tendrils of gas to catch it all in the eyepiece.

Sunday, August 15, 2010

The Witches Broom

Click on image for a larger view
Just got back from one hell of a hot camping trip.  I spent eight days in 100 degree weather with a few amateur astronomer friends at the Astronomical Society of Kansas City's Dark Sky Site (near Butler, MO).  Thankfully, night time temperatures were in the 70's and night time is why I was there.  Six out of those eight nights were clear and therefore I got a chance to image several deep sky objects with my telescope.  The image above is one of those objects.

The Veil Nebula image is only part of a much larger complex of nebulosity also known as the Cygnus Loop.  This part is on the west side of the "loop", so it is also called the "Western Veil".  A much more descriptive name is the "Witches Broom".   It's true identity, however, is the leftover remnants of a supernova explosion. some 5000 to 8000 years ago.  The remnants have since expanded to a circular area some 3 degrees in diameter.  An area this big would fit 6 full moons across.  Even though it covers an area so big in the sky, it is rather faint and requires optical aid to see it.  The bigger the telescope, the brighter it gets.  Even getting images of this object is not easy.  I haven't been happy with previous images, but this time using my 7.5" Mak-Newt telescope, I took 10 images, each image 15 minutes long, for a total of 2.5 hours combined, calibrated those images with "Bias, Flat and Dark" images, then spent a few hours bringing out the details with Photoshop.  Not a simple "click", but hours of work for one image.

Technical Details:
* Telescope: 190mm (7.5") Orion Maksutov-Newtonian
* Focal Length: 1007mm
* Focal Ratio: f/5.3
* Mount: Celestron CGE
* Exposures:
> 10 Lights, 15 minutes long
> 20 Biases
> 20 Flats
> 1 Dark
* Calibration: Removed bad pixels on Lights using the single Dark with "Nebulosity" software
* Processing: Aligned and Stacked using "DeepskyStacker" software
* Finished: Photoshop CS3