Over the last 18 years, astronomers have observed the formation of a massive new star, dubbed W75N(B)-VLA 2. A pair of images of a young star, taken 18 years apart, has revealed dramatic differences providing astronomers with a one of a kind "real time" look at how massive stars develop during the earliest stages of their formation.
Astronomers used the National Science Foundation's Karl G Jansky Very Large Array to study the massive young star, located approximately 4200 light years from Earth. The astronomers compared an image taken in 1996 with one taken in 2014 to see the dramatic differences. The images were then published this week in the journal Science.
"The comparison is remarkable," lead author of the study from the National Autonomous University of Mexico, Carlos Carrasco-Gonzalez says. The compact, rounded wind indicated by data from 1996 transforms - just 18 years later in 2014 - into a "distinctly elongated outflow".
Scientists believe that the new star formed in a dense, gaseous environment surrounded by a doughnut shaped, dusty torus.
Thanks to the study, scientists have discovered that during the star's birth it experienced episodes in which it ejected a hot, ionized wind for several years. The wind expanded in all directions, forming a spherical shell around the star until it hit the dusty torus, slowing its progression. Wind expansion, outward along the poles of the torus where there was less resistance, moved far more quickly, resulting in an elongated shape of the outflow.
Professor Huib van Langevelde from Leiden University in the Netherlands, who was also involved in penning the journal, said that, "this object is providing us an exciting opportunity to watch the developments over the next few years, as this very young star develops the characteristic bipolar outflow morphology."
The star in question is estimated to be about 8 times more massive and 300 times brighter than the Earth's Sun. Being able to observe its dramatic growing pains in real time is unique, according to Langevelde. One of the major findings that has already emerged relates to a 2009 study performed by JIVE scientists who traced the magnetic field in that region of space and found that the field surrounding the young star was neatly aligned with it.
The team hopes to watch and learn more, as the "protostar" continues its turbulent development. Dr Gabriele Surcis, who is working on the study, says that "our understanding of how massive young stars develop is much less complete than our understanding of how Sun-like stars develop."
"It's going to be really great to be able to watch one as it changes."
