The Crab Nebula
JAN 30, 2011
The Crab Nebula is the remnant of a supernova explosion that took place in
1054 AD. The bright supernova was recorded by both Chinese and
Arab astronomers at the
time. The supernova was bright for a few weeks or months but eventually it
faded. Today, it is a faint object that is hard to see visually from light
polluted skies. But, the light emitted by the expanding cloud of gas
consists mostly of a few specific wavelengths and therefore nice pictures
can be taken even with modest equipment provided appropriate narrowband
filters are used. The picture shown here was taken with my 10 inch
reflecting telescope and is a combination of images taken with
Hydrogen-alpha (red) and Oxygen-III (blue-green) filters.
  --Bob