After using the Atacama Large Millimeter/submillimeter Array (SOUL) to observe star-forming regions in the Large Magellanic Cloud, an investigation team discovered the existence of a turbulent tug-of-war phenomenon in the 30 Doradus incubator. The observations revealed that, despite strong stellar feedback, gravity is influencing the shape of the molecular cloud and, against all odds, promoting the formation of young, massive stars.
The results of the observations were presented in a Press conference during the assembly 240 of the American Astronomical Society (AAS, in its acronym in English), held in Pasadena (California, USA), and were published in the journal The Astrophysical Journal (ApJ).
30 Doradus is a large stellar nursery located very close to the Milky Way (it is only 170,000 light years away), in the heart of the famous Tarantula Nebula, in the Large Magellanic Cloud. There is the largest star cluster in the cosmic neighborhood – a perfect object of observation for those seeking to study the birth and evolution of stars. At the center of 30 Doradus is a brilliant stellar nursery that has been the cradle of more than 800,000 stars and protostars, including half a million hot, massive young stars. This region is of particular interest to those studying star formation and galaxy evolution due to the effect of gravity and stellar feedback.
Tony Wong, a professor at the University of Illinois at Urbana-Champaign and lead author of the new study, commented, “We thought that in the parts of the cloud closest to the young, massive stars we would see the clearest signs that gravity was overwhelmed by feedback and, consequently, there was less star formation. Instead, our observations confirmed that even in an extremely active feedback zone, gravity is still quite strong and star formation is likely to continue.”
Unlike the Milky Way, which has a relatively slow star formation rate of about seven stars (equivalent to four solar masses) per year, the star incubators of 30 Doradus’s host galaxy, the Large Magellanic Cloud, they experience real ups and downs that are often followed by frenetic periods of star birth. The team hopes that the new findings, along with future research, will shed light on the differences between the Milky Way and other more active nursery galaxies, and help understand how competition between gravity and feedback influences the shape of molecular clouds and affects the rate at which new stars form.