Boiling 'baby bubble' where stars are born comes into view - Livescience.com
The bubble surrounds the Westerlund 2 star cluster, one of the brightest star-forming regions in the Milky Way.The new image shows that the star cluster is surrounded by a single bubble of gas, not two as previously hypothesized, and that it's likely to keep birthing stars well into the future. .
"When massive stars form, they blow off much stronger ejections of protons, electrons and atoms of heavy metal, compared to our sun," study lead author Maitraiyee Tiwari, a postdoctoral associate in astronomy at the University of Maryland, said in a statement.We observed just such a bubble centered around the brightest cluster of stars in this region of the galaxy, and we were able to measure its radius, mass and the speed at which it is expanding.".
Westerlund 2 was identified in the 1960s, but previous images of the star-forming cluster were based on radio waves and long-wavelength signals called submillimeter waves, which could provide only a rough outline of the star cluster and didn't provide much detail about the gas bubble.They were also able to track the bubble's history: About a million years ago, the bubble "popped" on one side, sending a stream of charged gas called plasma streaming into space and slowing down star formation temporarily.
"This suggests stars will continue to be born in this shell for a long time, but as this process goes on, the new stars will become less and less massive.".