M1 – The Crab Nebula in Taurus

Telescope: Meade SN8 at f/4, Orion Atlas EQ-G
Camera: ZWO ASI071MC, Orion Imaging Skyglow Filter
Sensor Temperature: 0C, Gain: 200, Offset: 50
Guide scope: Williams Optics 50mm, Meade DSI Pro II, PHD
Exposure: 17x180sec saved as FITS
Darks: 32x180sec saved as FITS
Flats: 32x0.005sec, Tee-shirt flat, touched up with a synthetic flat
Average Light Pollution: Red zone, fair transparency
Lensed Sky Quality Meter: 18.6 mag/arc-sec^2
Stacking: Mean with a 2-sigma clip.
White Balance: Nebulosity Automatic
Software: Nebulosity, Deep Sky Stacker, Photoshop

This is M1, the Crab Nebula in Taurus (the Bull). M1 is a supernova remnant; the remains of a star that ended its life in one of the most violent events in nature. This particular supernova erupted in 1054 and the star became so bright that it was visible in broad daylight for 23 days. The resulting nebula is expanding so fast that it can be detected in images taken a few years apart. At the heart of the nebula is a pulsar; a neutron star spinning at over 30 revolutions per second.

After a long night of imaging I had about 50 minutes before the start of astronomical twilight, so I started a sequence on M1 and went to bed. I got up a couple of hours later to a white screen and PHD complaining that it had lost the guide star. Smile Taking a quick look at the source images showed the first 17 looked pretty good, and then I could see the first blush of sunlight illuminating the upper atmosphere. Kinda neat!

-John

M1 (8-25-2017)-1j.jpg