Sharpless 112

In 1959 U.S. astronomer Stewart Sharpless published a catalog of 312 Hydrogen-II emission nebulae. This is number 112, a faint nebula in the constellation Cygnus, about 5,500 light years from us. Radiation from star +45 3216 – about 30 times the size of the Sun – ionizes the hydrogen gas, causing it to glow. This nebula is near the plane of the Milky Way in a vast region of hydrogen. I processed the image to show this faint surrounding red ionized gas.


Exposure  • 13 hours (78 X 10 minutes) @ -15°C
   ☞ 25 full color
   ☞ 53 with Hα filter
 • Dusk flats
 • Camera position angle: 0°
Processing  • With PixInsight:
   ☞ Calibrate, star-align, integrate subframes
   ☞ Histogram transformation
   ☞ TGV Denoise, Curves
 • Final tweaking and sizing in Photoshop CS6
Date and Location  • 2022: June 25 & 27, July 3
 • Louisa County, Virginia, USA
Equipment
 • TMB-130SS APO refractor @ f/7 on an A-P 1200 mount
 • ZWO ASI-1600MC Pro color camera
 • Guided with a ZWO ASI-120M camera on a 60mm f/5 scope
 • Imaging and autoguiding with MaxIm DL 6.20
 • Automated image acquisition with ACP Observatory Control


Updated March 20, 2024