SH2 261 “Lower’s Nebula” is an emission nebula 6000 light years away in the constellation of Orion.
It is infrequently imaged perhaps because it is quite faint, especially the OIII component.
The field itself contains several bright and dark nebulae and is predominantly Hydrogen Alpha.
The primary source of ionization of the nebula is the star star HD 41997.
It is definitely worth an astrophotography visit.
Imaged in SHO Hubble palette and RGB for star color on my Planewave DR 350 at Observatorio El Sauce, Chile.
Image acquisition and processing: Mike Selby