Supernava remnant in the constellation of Cygnus.
Sh2-91 is part of the Supernava remnant G 65.3 + 5.7 in the constellation Cygnus, near the star Albireo, beta Cyg.
|Date of exposures:||07.09.2021, 08.09.2021, 22.09.2021|
|Exposures:||RGB: 70 x 180", Ha: 30 x 480", OIII: 32 x 480", Sum: 11,75 hrs|
|Telescope:||10'', F4 Newton|
|Focal length:||1000 mm|
|Filter:||Astrodon RGB E-Series, H-Alpha 5nm, OIII 3nm|
|Camera:||ASI 1600 MMC Pro|
|Guiding:||Off Axis Guider, Lodestar|
Sh2-91 is the remnant of a supernova that occurred about 30,000 years ago in the constellation of Cygnus at a distance of about 1,400 light-years. The shock wave, propagating at about 30,000 km/s, compresses and heats the interstellar matter to such an extent that the gas is ionized and excited to glow.
The entire SNR is oval shaped, and about the same size as the much better known Cirrus Nebula, also found in Cygnus. However, G 65.3 + 5.7 or Sh2-91 is considerably fainter than the Cirrus Nebula. Probably for this reason only few images of this region are seen.