University of Arizona | 2018 Jul 25
In a unique study, University of Arizona astronomy students searched 101 clouds of gas to find those that may be in the first phases of forming massive stars.
For three years, Jenny Calahan led fellow undergraduate students at the University of Arizona (UA) in research to help unravel the mystery of how the galaxy's most massive stars are born. ...
- The yellow balls seen at the center of this image are a phase of massive star formation that comes before the massive stars have cleared cavities in the clouds of gas around them (shown in green) but after the cold, collapsing gas stage that Jenny Calahan and Yancy Shirley searched for in their survey. (Credit: NASA/JPL-Caltech/Spitzer)
Astronomers understand this process for stars the size of our Sun. Particles in clouds are attracted to each other and begin to clump together. Gravity takes hold and the gases flow to the center of the cloud as it collapses. Over millions of years, the gas is put under so much pressure that it begins to burn, and the star is born when nuclear fusion finally begins in the core of the compressed gas.
Theories about how much gas and time it takes to make a star like our Sun can be proven through observations, because each stage of a Sun-like star's life -- from the collapse of gas clouds into a pre-stellar core to the star's expansion into a red giant and collapse into a white dwarf -- can be been seen throughout the galaxy.
But astronomers have yet to understand how stars more than eight times the mass of our Sun form. Stars of this size explode into supernovae at the end of their lives, leaving behind black holes or neutron stars. ...
Searching for Inflow Toward Massive Starless Clump Candidates
Identified in the Bolocam Galactic Plane Survey - Jenny K. Calahan et al