Tuesday 20 November 2012

The Swan and Hubble's variable nebulae

M17, The Omege or Swan nebula. This bright emission nebula lies in the constellation of
Sagittarius at a distance of about 5,000 light years. This object is about 15 light years
in diameter. This unguided image was taken using an Atik 314 L CCD camera, a ten inch
f/4.8reflector. Sixty second sub-frames was captured with matching dark-frames . Total
exposures times of five minutes for each colour filter were used and thirty minutes for
the luminance channel in H-alpha:



NGC2261, Hubbles variable nebula. This reflection nebula lies deep in the constellation
Monoceros the Unicorn at a distance of about 2,500 light years. This unguided image was
taken using an Atik 314L CCD camera, a ten inch, f/4.8 reflector. 60 second sub frames
were captured making total exposure times of twenty minutes for each colour channnel: