by Jean-Baptiste Auroux » Mon Feb 26, 2024 3:32 pm
NGC 6888 in high definition
Full version :
https://cdn.astrobin.com/thumbs/JqETqYP ... TZ0INm.png
Full version :
https://cdn.astrobin.com/thumbs/k8Z0P1p ... TZ0INm.jpg
The Crescent Nebula (NGC 6888) is an emission nebula in the constellation Cygnus, around 5,000 light years away.
This envelope of matter is produced by a very special type of star, a "Wolf-Rayet star", named after the two astronomers from the Paris Observatory who discovered this type of star using spectroscopy in 1867: these are hot stars, probably the offspring of stars of spectral type O and B (i.e. the hottest and most massive stars in existence) that have just left the main sequence and are therefore entering the final stages of their lives.
The Crescent, visible in the photograph shown here, represents the zone of influence of the stellar wind from the central star WR-136, whose surface temperature is extremely high, estimated at 70,000K. The size of this bubble is considerable, extending over 25 light-years! By way of comparison, the Sun's heliosphere, i.e. the zone of influence of its solar winds, is no more than 12 light-years long.
The material making up the envelope was ejected from the star 400,000 years ago, so we can estimate its current expansion speed at around 50 km/s. At the time of the ejection, however, the speed was much higher, estimated at 1400 km/s.
Astronomers estimate that WR-136 should explode as a supernova in the "near future" (on the scale of the Universe), in 100,000 to 1 million years.
TEC 140 - Temma 200 - ASI 6200 MM pro - Chroma Filters (3nm)
Ha : 217 x 120s
OIII : 910 x 120s
Total : 37h34
23 July to 20 August 2023 - Corsica (France)
Pixinsight & PS
Copyright: Team OURANOS (Jean-Baptiste Auroux, Jean Claude Mario, Mathieu Guinot & Matthieu Tequi).
https://team-ouranos.fr/
https://www.astrobin.com/users/Team_OURANOS/
[size=120][b]NGC 6888 in high definition[/b][/size]
[img2]https://team-ouranos.fr/wp-content/uploads/2024/02/NGC6888_vdef_crop1_mini.jpg[/img2]
Full version : https://cdn.astrobin.com/thumbs/JqETqYP0Jikc_16536x0_ieTZ0INm.png
[img2]https://team-ouranos.fr/wp-content/uploads/2024/02/NGC6888_vdef_logo_miniapod.jpg[/img2]
Full version : https://cdn.astrobin.com/thumbs/k8Z0P1paJz0R_16536x0_ieTZ0INm.jpg
The Crescent Nebula (NGC 6888) is an emission nebula in the constellation Cygnus, around 5,000 light years away.
This envelope of matter is produced by a very special type of star, a "Wolf-Rayet star", named after the two astronomers from the Paris Observatory who discovered this type of star using spectroscopy in 1867: these are hot stars, probably the offspring of stars of spectral type O and B (i.e. the hottest and most massive stars in existence) that have just left the main sequence and are therefore entering the final stages of their lives.
The Crescent, visible in the photograph shown here, represents the zone of influence of the stellar wind from the central star WR-136, whose surface temperature is extremely high, estimated at 70,000K. The size of this bubble is considerable, extending over 25 light-years! By way of comparison, the Sun's heliosphere, i.e. the zone of influence of its solar winds, is no more than 12 light-years long.
The material making up the envelope was ejected from the star 400,000 years ago, so we can estimate its current expansion speed at around 50 km/s. At the time of the ejection, however, the speed was much higher, estimated at 1400 km/s.
Astronomers estimate that WR-136 should explode as a supernova in the "near future" (on the scale of the Universe), in 100,000 to 1 million years.
TEC 140 - Temma 200 - ASI 6200 MM pro - Chroma Filters (3nm)
Ha : 217 x 120s
OIII : 910 x 120s
Total : 37h34
23 July to 20 August 2023 - Corsica (France)
Pixinsight & PS
Copyright: Team OURANOS (Jean-Baptiste Auroux, Jean Claude Mario, Mathieu Guinot & Matthieu Tequi).
https://team-ouranos.fr/
https://www.astrobin.com/users/Team_OURANOS/