Galaxies & clusters




Solar system

Narrow band

Wide field






Canon 40D baader modified

Original          Diffraction spikes          50% crop          100% crop

The Crab Nebula (catalogue designations M1, NGC 1952, Taurus A) is a supernova remnant and pulsar wind nebula in the constellation of Taurus. The nebula was observed by John Bevis in 1731; it corresponds to a bright supernova recorded by Chinese and Arab astronomers in 1054. At X-ray and gamma-ray energies above 30 KeV, the Crab is generally the strongest persistent source in the sky, with measured flux extending to above 1012 eV. Located at a distance of about 6,500 light-years (2 kpc) from Earth, the nebula has a diameter of 11 ly (3.4 pc) and expands at a rate of about 1,500 kilometres per second.

At the centre of the nebula lies the Crab Pulsar, a neutron star (or spinning ball of neutrons), 28-30km across,[5] which emits pulses of radiation from gamma rays to radio waves with a spin rate of 30.2 times per second. The nebula was the first astronomical object identified with a historical supernova explosion.

The nebula acts as a source of radiation for studying celestial bodies that occult it. In the 1950s and 1960s, the Sun's corona was mapped from observations of the Crab's radio waves passing through it, and in 2003, the thickness of the atmosphere of Saturn's moon Titan was measured as it blocked out X-rays from the nebula.

The cloudy remnants of SN 1054 are now known as the Crab Nebula. The nebula is also referred to as Messier 1 or M1, being the first Messier Object catalogued in 1758.

The above text is taken from Wikipedia.

Considering the short integration time (2hrs and 45min at f6.3) I was a surprised at how much signal that was captured. I guess it is the brightness of the Nebula that one should thank for that. The fall of 2010 has seen very few nights with clear skies, but this one was exceptionally good - which also helped.

By "mouse over" on the blue text just below the image you can see:

  • Original: the main processed image and the image that is displayed when you load this web page.

  • Diffraction spikes: I could  not help it, but I played a little with Carboni's PS tools to create some diffraction spikes. Just for fun :-)

  • 50% crop: A 50% crop of the original image

  • 100% crop: A 100% crop of the original image

 The following software has been used. MaximDL (image acquisition and guiding), CCDStack (calibration and de-convolution), PixInsight (cropping, background correction, colour corrections) and Photoshop CS5 (all the rest, incl Noel Carbonis Astronomy Tools).



Celestron C8 at f6.3

(using Ted Agos adapter)


33x300s = 2hr 45min





Autoguiding with MaximDL




StarlightXpress Lodestar

CALIBRATION: 32 Darks/32 Flats

Nov 7, 2010

LOCATION: Älta, Sweden







Copyright: All images © 2010 Matts Sporre. All Rights Reserved