Astronomers have identified a young star, located almost 11,000 light years away, which could help us understand how the most massive stars in the Universe are formed. This young star, already more than 30 times the mass of our Sun, is still in the process of gathering material from its parent molecular cloud, and may be even more massive when it finally reaches adulthood.
The researchers, led by a team at the University of Cambridge, have identified a key stage in the birth of a very massive star, and found that these stars form in a similar way to much smaller stars like our Sun - from a rotating disc of gas and dust. The results will be presented this week at the Star Formation 2016 conference held at the University of Exeter, and are reported in the Monthly Notices of the Royal Astronomical Society.
In our galaxy, massive young stars - those with a mass at least eight times greater than the Sun - are much more difficult to study than smaller stars. This is because they live fast and die young, making them rare among the 100 billion stars in the Milky Way, and on average, they are much further away.
"An average star like our Sun is formed over a few million years, whereas massive stars are formed orders of magnitude faster -- around 100,000 years," said Dr John Ilee from Cambridge's Institute of Astronomy, the study's lead author. "These massive stars also burn through their fuel much more quickly, so they have shorter overall lifespans, making them harder to catch when they are infants."
The protostar that Ilee and his colleagues identified resides in an infrared dark cloud - a very cold and dense region of space which makes for an ideal stellar nursery. However, this rich star-forming region is difficult to observe using conventional telescopes, since the young stars are surrounded by a thick, opaque cloud of gas and dust. But by using the Submillimeter Array (SMA) in Hawaii and the Karl G Jansky Very Large Array (VLA) in New Mexico, both of which use relatively long wavelengths of light to observe the sky, the researchers were able to 'see' through the cloud and into the stellar nursery itself.
By measuring the amount of radiation emitted by cold dust near the star, and by using unique fingerprints of various different molecules in the gas, the researchers were able to determine the presence of a 'Keplerian' disc - one which rotates more quickly at its centre than at its edge.
"This type of rotation is also seen in the Solar System - the inner planets rotate around the Sun more quickly than the outer planets," said Ilee. "It's exciting to find such a disc around a massive young star, because it suggests that massive stars form in a similar way to lower mass stars, like our Sun."
The initial phases of this work were part of an undergraduate summer research project at the University of St Andrews, funded by the Royal Astronomical Society (RAS). The undergraduate carrying out the work, Pooneh Nazari, said, "My project involved an initial exploration of the observations, and writing a piece of software to 'weigh' the central star. I'm very grateful to the RAS for providing me with funding for the summer project -- I'd encourage anyone interested in academic research to try one!"
From these observations, the team measured the mass of the protostar to be over 30 times the mass of the Sun. In addition, the disc surrounding the young star was also calculated to be relatively massive, between two and three times the mass of our Sun. Dr Duncan Forgan, also from St Andrews and lead author of a companion paper, said, "Our theoretical calculations suggest that the disc could in fact be hiding even more mass under layers of gas and dust. The disc may even be so massive that it can break up under its own gravity, forming a series of less massive companion protostars."
The next step for the researchers will be to observe the region with the Atacama Large Millimetre Array (ALMA), located in Chile. This powerful instrument will allow any potential companions to be seen, and allow researchers to learn more about this intriguing young heavyweight in our galaxy.
This work has been supported by a grant from the European Research Council.
Sarah Collins | EurekAlert!
Subnano lead particles show peculiar decay behavior
25.04.2018 | Ernst-Moritz-Arndt-Universität Greifswald
Getting electrons to move in a semiconductor
25.04.2018 | American Institute of Physics
At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.
Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...
Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.
Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...
University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.
Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.
Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.
Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...
Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.
The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...
13.04.2018 | Event News
12.04.2018 | Event News
09.04.2018 | Event News
25.04.2018 | Physics and Astronomy
25.04.2018 | Physics and Astronomy
25.04.2018 | Information Technology