Cygnus OB2: Probing A Nearby Stellar Cradle

 

Deep observations with NASA’s Chandra X-ray Observatory of Cygnus OB2 have been used to detect the X-ray emission from the hot outer atmospheres, or coronas, of young stars in the cluster and to probe how these great star factories form and evolve. About 1,700 X-ray sources were detected, including about 1,450 thought to be stars in the cluster. In this image, X-rays from Chandra (blue) have been combined withinfrared data from NASA’s Spitzer Space Telescope (red) and optical data from the Isaac Newton Telescope (orange).

Young stars ranging in age from one million to seven million years were detected. The infrared data indicates that a very low fraction of the stars have circumstellar disks of dust and gas. Even fewer disks were found close to the massive OB stars, betraying the corrosive power of their intense radiation that leads to early destruction of their disks. 

 

Infrared Image of Cygnus OB2

Credit: NASA’s Spitzer Space Telescope

 

Evidence is also seen that the older population of stars has lost its most massive members because ofsupernova explosions. Finally, a total mass of about 30,000 times the mass of the sun is derived for Cygnus OB2, similar to that of the most massive star forming regions in our Galaxy.

 

Optical Image of Cygnus OB2

NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra’s science and flight operations from Cambridge, Mass.