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Cas A SNR   © Ken Crawford      Rancho Del Sol Observatory  MPC G67
Image Exposure Details
Filter Exposures
Clear/ Lum 240 minutes
Red 180 minutes
Green 180 minutes
Blue 180 minutes
Ha 5nm 540 minutes
OIII 3nm 360 minutes
SII 5nm 0 minutes

Cassiopeia A (Cas A) is a supernova remnant around 11,000 light-years away. Though it is very faint in optical light, it is one of the brightest extra solar radio sources in the sky. The lower right image shows the X-ray engery from NASA NuSTAR overlaid on top of Ken Crawford's optical image. Cas A Comparision link HERE. You may also see this image and write-up at NASA APOD.
RCOS 20" carbon truss - 100mm FFC
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Cas A SNR revealed with over 28 hours of total exposure time. Cas A X-ray data credit NASA/JPL-Caltech/DSS.

These images may be used for personal or educational use without contacting me. But, these images and this website are Copyright © Ken Crawford. If you are a publisher and would like a full resolution link to this or other images please contact Ken Crawford.
Cas A and X ray