Monday, Sep 8, 2025

On this occasion I captured Sh2-91, a filament of gas and dust located about 2,600 light years away in the constellation of Cygnus. This fragile structure is part of a gigantic remnant of a supernova that exploded tens of thousands of years ago. The study of Sh2-91 allows us to see how the shock waves of a supernova interact with the interstellar medium, drawing delicate structures of gas and dust that would normally remain invisible. This image was obtained with Hα, OIII and SII-OIII filters, integrating a total of 103 hours of exposure to highlight details invisible to the naked eye and show the subtle colors and structures of this celestial object. Date of capture: 06_07_08/2025 Total exposure: 6180 minutes = 103 hours Askar D1 filter: 364 x 10 min = 3,640 min (≈ 60.7 h) Askar D2 filter: 249 x 10 min = 2,490 min (≈ 41.5 h) L-quad: 50 x 1 min = 50 min (≈ 0.83 h) Bortle 5 📌 Albatàrrec (Lleida) Spain