More Backyard Astronomy July 27, 2020. One of my favorite emission nebulae is the Veil Nebula in the Constellation Cygnus. This is the Western portion of the much larger Veil Nebula. This part of the Veil in my photograph is also called the Witch's Broom. NGC6960 is a glowing cloud of ionized gas left from an explosion or supernova of a star. This star must have been about 20 times more massive than our sun and exploded approximately 10,000 to 20,000 years ago. This Western portion of the nebula is a small part of an almost circular loop covering 3 degrees of the sky or six times the diameter of the moon! The best estimate of the width of this Cygnus Loop is 2,400 light years across. The Veil Nebula is approximately 1,470 light years away from earth. It takes less time for light to reach earth than from one side of the nebula to the other.

The Hubble Space Telescope analyzed the gas in the nebula and found it to be made up mostly of Hydrogen, Oxygen and Sulfur gases. To capture this photograph I used three different filters, and you guessed it, I used three, a Hydrogen Alpha (Ha}, Oxygen, and a Sulfur II filter. To do this photo I took 15 three minute exposures of the nebula in turn through each of the three filters. When I was done a stacked all of the photos, and allowed the stacking program to stack them in their native gaseous colors to obtain the first photograph as the Hubble Telescope would have taken the photo. This color process is referred to as "The Hubble Pallet" or SHO ,which stands for Sulfur, Hydrogen and Oxygen.

Having processed the data as SHO, I then labeled the three sets of photographs Red, Green and Blue in color labeling portion of the software, a process called "Mapping the Colors" and obtained a photographed called an "RGB" or "false color." RGB is like an old monitor on a computer. The RGB is the abbreviation for Red, Green and Blue. The top photograph is the "SHO" photo and the bottom is the "RGB" determined by my incredible powers of logical deduction . There is some change in the colors in the photographs, which are not obvious to me as I am color blind, so, I will have to leave it to you to analyze them for me. What is apparent is that there are differences in the details brought out in the nebula by using these processes. A large monitor or laptop is best to view the photograph or stretch them on a cell phone to see the detail.

I am still working on this photograph as it is a work in progress. So far the exposure is 2 hours and 15 minutes. If the weather permits I will try to gather another couple of hours of exposure and post an updated picture. Thanks for looking!

Clear skies to you, Ken Adler- ***NOTE*** I only posted the RGB on Astrobin