An elongated section of one of the spiral arms of the galaxy M 51 in the constellation Hounds. The reddish areas are gas and dust from which stars form. The white dots show bright star clusters. © ESA/Webb, NASA & CSA, A. Pedrini, A. Adamo (Stockholm University) and the FEAST JWST team
New images from the James Webb Space Telescope show different phases in the formation of a star cluster. This allows researchers to better understand the early phases of star formation, when they are still surrounded by a “birth cloud”.
The image shows the spiral galaxy Messier 51 (M 51) and was taken with the James Webb Telescope’s Near Infrared Camera (NIRCam). In the galaxy, about 27 million light-years away, dense clumps of star-forming gas can be seen in red and orange. Within the gas complexes are extremely bright clusters of massive stars scattered throughout the galaxy arm. Many of them are obscured by dust clouds, but could be made visible using infrared light.
The data from the James Webb Telescope in combination with data from the Hubble Space Telescope now helped an international team of researchers led by Angela Adamo from Stockholm University to better understand the process of star formation. Stars form when clouds of gas and dust collapse under the influence of gravity. These collapsing clouds produce more and more stars until the cloud is dispersed by strong stellar winds, intense ultraviolet radiation, and the explosions of massive stars. This stops star formation and the light from the stars can influence gas clouds and star formation in other regions of the galaxy. This process, called “stellar feedback,” ensures that most of the gas never forms stars.
The researchers examined images of four nearby galaxies from the FEAST observation program (#1783). Almost 9,000 star clusters in different stages of development were identified: young clusters that are just emerging from the natal cloud, clusters that have already partially displaced the gas and completely exposed clusters. The results show that it is the most massive star clusters that shed their gaseous shell the fastest and begin to light up their galaxy earliest.