The Crescent nebula and its central star WR136

Image Title: The Crescent nebula and its central star WR136

Date image was taken: November 04, 2023

Location: Romano d'Ezzelino (Italy)

Image Description and Details: This is a composition of several different exposures of the Crescent Nebula, imaged with broad and narrowband filters, with a spectral analysis of its central Wolf Rayet Star WR136. The star emits mostly in the ionized helium line, with a peak centered in the blue wavelenghs. It lost its hydrogen outer atmosphere, that generated the Crescent nebula many years ago in a catastrophic event. By measuring the broadening of Helium's spectral lines it is possible to estimate the expansion speed of the hot gas surrounding the star, also with amateur instruments: from 1500 to 2000 km/s

Equipment Details: Crescent nebula: C11HD Edge working at f/7 + ASI2600MM Pro + Optolong RGBSHO filters

WR136 Spectrum: Tecnosky 115/800mm + StarAnalyzer 200 + ASI183MM

Copyright: Alessandro Ravagnin

Website or Facebook Profile: https://astrotrex.wordpress.com/2023/07/19/wolf-rayet-136-and-the-crescent-nebula-ngc6888/