Waves of Hydrogen-alpha and the Crescent Nebula

Jarrett Trezzo
Location of photo
Tampa Bay, FL
Date/Time of photo
June 2, 9, & 18, 2018
Edge HD 925 + Hyperstar 3, QHY 247C, Baader UV/IR Cut, Astronomik 12nm Ha, Baader 8.5nm OIII
7.5 hours total integration (3 hr Ha, 3 hr OIII, 1.5 hr RGB. The Crescent Nebula is located in Cygnus near the star Sadr, about 5000 light-years away from Earth. At the heart of the Crescent is the Wolf-Rayet star WR 136. A Wolf-Rayet star, one of the most luminous and hottest types of stars, is the next stage in the short life of a massive star. After the red giant stage and the expulsion of its hydrogen layer, the Wolf-Rayet stage is the “last hurrah” before it goes supernova. The waves seen here in the Crescent are the result of a fast stellar wind caused by the rapid ejection of hot mass from WR 136 colliding with the slower moving, cooler gas previously ejected by the star when it was in the red giant stage. The force of the collision between the two creates shock waves moving in opposite directions from each other and the excitation causes the gases to glow.
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