ALMA | NAOJ | NRAO | ESO | 2019 Jul 08
Astronomers obtained the first detailed face-on view of a gaseous disk feeding the growth of a massive baby star. They found that it shares many usual features with lighter baby stars, implying that the formation process is the same, regardless of the final mass. This finding paves the way for a better understanding of star formation.
A protostar, a baby star still in the process of forming, is fed by a surrounding disk of gas falling towards the center. The details of the process, such as why stars form with a wide range of masses, are still unclear. Low mass stars forming in the vicinity of the Solar System, allow astronomers to see the process up-close. On the other hand, massive protostars are rare, and even the nearest are quite far away from us. ...
ALMA observations captured a rotating disk around G353 with a radius eight times larger than the orbit of Neptune. This sounds huge, but it is one of the smallest disks yet found around a massive protostar. ALMA also found an envelope of gas surrounding the system three times larger than the disk. ...
Interestingly, the disk is not uniform; its south-eastern side is brighter than other parts, being the first time astronomers have seen an asymmetric disk around a massive protostar. The team also found instability in the disk which is going to fragment; which might be causing the asymmetry. These features are often seen around smaller protostars, suggesting that the essential physical processes are the same in low-mass and high-mass star formation. ...
The First Bird's-eye View of a Gravitationally Unstable Accretion Disk in High-Mass Star Formation ~ Kazuhito Motogi et al
- Astrophysical Journal Letters 877(2):L25 (2019 Jun 01) DOI: 10.3847/2041-8213/ab212f
- arXiv.org > astro-ph > arXiv:1905.12983 > 30 May 2019