University of Leeds, UK | 2015 Oct 28
Observations led by astronomers at the University of Leeds have shown for the first time that a massive star, 25 times the mass of the Sun, is forming in a similar way to low-mass stars.
[c][attachment=0]afgl-4176.jpg[/attachment][/c][hr][/hr]The discovery, made using a new state-of-the-art telescope called the Atacama Large Millimeter/submillimeter Array (ALMA), which is based in Chile, South America, is published online today by The Astrophysical Journal Letters.
Lead author Dr Katharine Johnston, from the School of Physics and Astronomy at the University of Leeds, said: “Our groundbreaking observations show that not only does this still-forming massive star feed from a disk of material that surrounds it, like young Sun-like stars do, but it also mirrors low-mass star formation in the way the disk spins around the star.
“Without a disk to channel material onto the forming star in a thin and dense layer, energetic processes, such as stellar winds from these hot stars, would halt the material before it could reach the star. It’s like when the wind stops you in your tracks on a windy day.”
The research is one of the final pieces of the puzzle in understanding the lifetimes of the most massive and luminous stars, called O-type stars. These stars are major contributors to heavy element production in the Universe, such as iron and gold, which they eject into space in dramatic supernovae explosions at the end of their lives.
Bit by bit, evidence for massive stars forming in a similar way to low-mass stars has been growing. However, until now, rotating disks that look exactly like the ones around low-mass stars were only seen around B-type stars, which are less than 18 times the mass of the Sun. ...
How do massive stars get their mass? Astronomers find disk around young massive star
Max Planck Institute for Astronomy | 2015 Oct 29
A Keplerian-like disk around the forming O-type star AFGL 4176 - Katharine G. Johnston et al
- Astrophysical Journal Letters 813(1):L19 (2015 Nov 01) DOI: 10.1088/2041-8205/813/1/L19
arXiv.org > astro-ph > arXiv:1509.08469 > 28 Sep 2015