CYGNUS LOOP
This image captures most of the western half of the Cygnus Loop, the overall supernova remnant which includes the Western Veil and Pickering's Triangle. The image orientation is such that it presents the field as viewed while facing south as the loop crosses the meridian, and at my 37° latitude this is about 7° south of the zenith (nicely placed high overhead).
The filaments of Pickering's Triangle are seen extending down from the top of the image. It, and the rest of the loop, are estimated to be 2100 ly distant.
A fascinating and informative paper "
The Cygnus Loop/Veil Nebula Hubble Space Telescope" gives the following interesting description of the source of the emitted light:
"However, even though each of these colors arises from a different chemical element, the variations we see here are not from varying chemical abundances with position! (All of the gas in the cavity wall is very nearly the same chemical composition since it is interstellar gas, not the ejecta from the supernova.) Rather, the different colors are primarily showing us variations in temperature and density of the emitting material."The bright star is 52 Cygni, and the filaments of the Western Veil stand out brightly in its background. 52 Cygni is a 4th magnitude binary star, 201 ly distant (very much in the foreground, not near to the filaments of the Veil). It's interesting to note that the magnitude 9.5 secondary star is 6.6 arcseconds separation from the primary, and at a position angle of 70° this can just be seen in my image as a slight bulge at the 10 o'clock position of the star (more clearly seen before stretching).
PROCESSING
The stars in this field compete strongly for attention over the wispy light coming from the Veil. I used Adam Block's technique of
Star Reduction to put more emphasis on the nebula.
Galaxy ViewCS/Trace
Comments