Sh2-73 Nebula

Bob Franke
Location of photo
Chino Valley, AZ
Date/Time of photo
4/30/2014 to 6/20/2014
Takahashi FSQ-106ED scope, Losmandy G11 mount, SBIG STF-8300M camera, Baader LRGB filters. Total exposure = 27.75 hrs.
Sh2-73 is located in the constellation Hercules and was mistakenly included in the Sharpless catalog as an emission nebula. We now know that the nebula is simply a molecular cloud. With its relatively high galactic latitude, about 45°, the integrated light of the galaxy illuminates the nebula. Therefore, we can refer to Sh2-73 as an integrated flux nebula, as defined by Steve Mandel.