The Crab Nebula (which looks nothing like a crab in photos) is one of the iconic nebulae in the night sky. It’s even the first entry in Charles Messier’s famous list of non-comets. His “junk list” is our treasure trove since it contains some of the most stunning jewels of the night.
The Crab is one of the few objects that humans have seen come into existence in recorded history. In 1054, Chinese astronomers noted a “new star” in the sky that was bright enough to be seen in daylight for a while. Eventually it faded from view. It wasn’t until fairly recently that we realized that the Crab Nebula was the remains of what they saw. The nebula is a supernova remnant. Essentially, it is the aftermath of an incredibly powerful explosion that sent much of the mass of the star hurtling out into space. All that remans of the star is a rapidly spinning neutron star known as a pulsar. We can’t see the pulsar but we can see the glowing gas that was hurled out into space.
The nebula is fairly small, only about seven arcminutes across or almost one fourth the diameter of the full moon. It’s too small and dim to be seen with the unaided eye but in dark skies it can be seen in binoculars and even small telescopes can see it visually.
This image is a narrowband image presented in the Hubble Palette, that is the Sulfur II is in the red channel, the hydrogen alpha in the green and oxygen III in the blue channel. The nebula is appears amazingly intricate with tendrils of gas appearing to emanate from a centralist point.
This is just over 13 hours of data split almost equally among the filters and was taken at a dark sky location in West Virginia.
You can find this image at astrobin.