Crab Nebula
Supernova Remnant in Taurus



M1: This is gas cloud which is the remnant of a huge star which exploded into a supernova in the year 1054 A.D. The original star, with perhaps ten times the mass of our Sun, remains at the center of this nebula, but it now contains perhaps 1.5 times the mass of our Sun, and has collapsed into a neutron star, with a diameter of ten miles, which rotates on its axis 30 times per second. The outer layer of gas is expanding at a rate of about 3 million miles per hour. It is about 6,500 light years from the Sun.


Technical Information:

LLRGB: 135:45:45:72 (Luminance layer consisted of 9 fifteen minute images; R and G comprised of 3 fifteen minute images; B comprised of 3 twenty-four minute images). L images unbinned; R, G and B binned 2x2.

Equipment: 10" LX200 at f/12, and an SBIG ST-8E camera/CFW-8 color filter wheel, guided by an SBIG AO-7 adaptive optics device, guiding at about 14.5 Hz for Lum.

Image Acquisition/Camera Control: CCDSoft V5.

Processing: All images calibrated (darks and dawn flats) and registered in AIP4WIN. Images average combined in Ray Gralak's sigma reject program. Five iterations of Richardson-Lucy deconvolution applied in CCDSharp. Iterative applications of curves and levels in Photoshop 6.0, followed by unsharp mask in Photoshop. Color combine performed in Photoshop 6.0.

Location: My yard in Redmond, Washington, elevation 500'.

Date: Luminance and R and G images taken during the night of 11/26/02; B images taken during the nights of 11/27/02.

CCD Temperature: Lum: -32C; RG: -32C; B: -30C

Moon Phase: Third Quarter

Seeing: 2.7 Arcsecond FWHM

Copyright Mark de Regt, 2002