H-II region on the edge of the Orion arm.
Sh2-261 is an H-II region on the outermost edge of the Orion arm of our Milkyway, on the border of the galactic region between the Orion and Perseus arm. The best time for its observation in the evening sky is between January and May, and although it is located in the northern hemisphere, it can be observed from all populated areas of the earth.
|Date of exposures:||11.11.2017, 18.11.2017, 22.11.2017|
|Exposures:||Ha: 12 x 1200 sec., RGB: 33 x 360 sec, sum: 7,3 hrs.|
|Telescope:||Takahashi Epsilon 130D|
|Focal length:||430 mm|
|Filter:||Astrodon H-Alpha 5nm, RGB E-Series|
|Guiding:||Off Axis Guider, Lodestar|
In addition to the prominent objects in Orion such as M42, the horse's head or the flame nebula, Lower's Nebula is very rarely shown. It is therefore hardly surprising that this object was discovered quite late in 1939 by Harold Lower and his son Charles in a astrophoto. The picture on which he was discovered was taken with a self-made 8-inch schmidt camera.
The nebula is about 3,200 light-years away from us, has a size of about 13.1 parsec and shines with an apparent surface brightness of about 10 mag. Above the bright star HD 41997 in the center of Sh2-261 a small reflection nebula is visible.