SH2-157, the Lobster Claw Nebula, is an emission nebula located about 11,000 light-years away in the constellation of Cassiopeia.
According to SHO palette, red/orange and predominantly yellow regions of the nebula evinced a very large H II region while the blue-colored are predominately regions featured by the emission of light from molecular oxygen.
On the top NGC 7635 – the Bubble Nebula, and on the middle the star cluster NGC 7510.
Region of SH2-157 and NGC7635 in narrowband filters, SHO palette. From Bortle 6th degree sky in Livorno, Italy – home balcony. William Optics Redcat 51 and ASI1600mm Pro cooled at -20 Celsius. Mount SW EQM35 Pro, setup ground on Asiair Pro.