Image acquired from my driveway in suburban West Knoxville.
November 1-3, 2003

Astro-Physics 1200 GTO mount with Nikon 180mm f/2.8 ED lens @ f/4 with Mandel Wide Field Imaging Adapter.
CFW-8a and 4.5nm Custom Scientific  Hydrogen Alpha filter
SBIG 10XME CCD
 

Simeis147 is a very large, very old Supernova remnant (SNR). It is one of the faintest objects in the sky and one of  four SNR's visible to people in the Northern hemisphere. The others being the crab nebula which is nearby also in Taurus, IC 443 in Gemini and the Veil nebula in Cygnus.  It was discovered using a 25" Schmidt camera in 1952 by G.A Shajn and V.E. Hase at the Crimean Astrophyical Observatory at Simeis (in the former U.S.S.R). It was also imaged independently at Palomar by the 48" Schmidt camera on red photographic plates at roughly the same time period.  Estimates on the age exceed that of 50,000 years, almost twice as old as the  more well known Veil Nebula in Cygnus. Expansion rates are much less than that of the Veil as well which would contribute to the much older age of Simeis147. Distance is estimated to be at over 3000 light years with an actual diameter being around 165 light years. Like other SNR's it has a complex filamentary structure and radio source.  The apparent size of the nebula is approximately  200 x 180 arc-minutes ( That's more than six full moon diameters)

My deepest exposure sequence to date. The image histogram had to be pushed hard to bring out the faint loops of blowing gas.
This object is incredibly dim.

765 minutes total integration time or 12.75 hours!!
( 1200 seconds x 9 ) and ( 2700 seconds x 13 )

also

More than 30 hours spent gathering calibration frames for this object.

Negative image available here.

Other images of this object

Steve Mandel
Stephan Messner
Loke Tan

Notes:  Selfguiding with integral guider chip.
Acquisition and calibration in Maxim DL/CCD with Sequencer II used for auto  image acquisition.
Sigma Reject combines with Russ Croman's Sigma Reject plugin.
Adobe Photoshop used for levels and curves adjustment.
 
 
 
 

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