Scientists utilize the ESO’s Atacama Pathfinder Experiment (APEX) telescope in order to monitor small, faint features of the Universe that can only be detected using millimeter and sub-millimeter wavelengths. It recently discovered a large amount cold, interstellar dust that is attributed to the birth of massive stars. Essentially, the team of scientists led by Timea Csengeri of the Max Planck Institute for Radio Astronomy in Bonn have discovered several stellar nurseries tucked away inside the Milky Way. The results of the study have been published in an open access format in the journal Astronomy & Astrophysics.
When massive stars die and explode into supernovae, a tremendous amount of dust and elements are ejected out at high speeds. Stellar wind and radiation affect the dust, and could possibly set it on the course to becoming a new star. Detecting the dust indicative of newborn stars is difficult for land-based telescopes, as water in the air can distort the signal. The APEX telescope has one of the highest altitudes of any observatory site in the world, located 5100 meters above sea level on the Chajnantor plateau in the Atacama desert in Chile. This area is also one of the most arid locations in the world, which minimizes atmospheric disturbance.
This choice location makes it possible for the APEX Telescope Large Area Survey of the Galaxy (ATLASGAL) to observe 97% of the inner Milky Way, which is everything found within our Sun’s galactic orbit, using a 0.87 mm wavelength. They were able to detect a large amounts of “dust cocoons” that occur around forming stars. The cocoons of gas and dust in these nurseries are so thick, the visible and infrared light generated by the inner newborn massive stars cannot penetrate through.
“Our team has now analyzed this survey revealing the largest sample of the so-far hidden places of massive star-formation”, Csengeri said in a press release. "We have identified many new potential sites where the most massive stars currently form in our Galaxy."
Scientists have already known that stars much more massive than our Sun live fast and die hard, but by analyzing these nurseries, they were also able to see how the life cycle of those massive stars impacts the next generation. The young stars took only 75,000 years to form. As a comparison, our Sun that has considerably lower mass took well over 10 million years to form. This is the first time that astronomers have collected evidence that stellar formation can occur so quickly within our galaxy.
This survey was the largest ever completed at the sub-millimeter scale. The wealth of stellar nurseries that were detected by the team will be targeted for future analysis using the ALMA interferometer, which will examine the sites in much higher resolution.
Image description, from the press release:
The ATLASGAL survey coverstwo thirds of the surface area of the Galaxy within 50,000 light years of the Galactic center. Thus it includes practically all (97%) of the star-formation within the Solar Circle, i.e. the inner Galaxy. The image displays a part of ATLASGAL, a region located between the giant molecular complexes called W33 and M17 in the Sagittarius constellation. Zooms in color scale show the 3-color emission from the mid-infrared GLIMPSE survey, and sub-millimeter dust emission from ATLASGAL is shown in red and traced with contours. One region corresponds to a cold, pristine massive clump (upper left inset), and another one to a young massive star (upper right inset). Both objects have sizes of only a few light-years across. In the lower right inset we present a schematic of the Milky Way and show the position of the Solar Circle (green) and region of the Galaxy covered by ATLASGAL (shaded region). © ATLASGAL Team