27 November, 2015
Dr Gemma Anderson
ICRAR – Curtin University
Ph: +61 8 9266 3577
M: +61 408 955 483
Dr James Miller-Jones
ICRAR – Curtin University
Ph: +61 8 9266 3785
M: +61 488 484 825
M: +61 423 982 018
An artist’s impression of a star being drawn toward a black hole and destroyed, triggering a jet of plasma made from debris left over from the stars destruction.
Credit: Modified from an original image by Amadeo Bachar.
Scientists have discovered a hungry black hole swallowing a star at the centre of a nearby galaxy.
The supermassive black hole was found to have faint jets of material shooting out from it and helps to confirm scientists’ theories about the nature of black holes.
The discovery was published today in the journal Science.
Astrophysicist Dr Gemma Anderson, from the Curtin University node of the International Centre for Radio Astronomy Research (ICRAR), said a supermassive black hole swallowing a star is an extreme event in which the star gets ripped apart.
“It’s very unusual when a supermassive black hole at the centre of a galaxy actually eats a star, we’ve probably only seen about 20 of them,” she said.
“Everything we know about black holes suggests we should see a jet when this happens but until now they’ve only been detected in a few of the most powerful systems.
“Now we’ve finally found one in a more normal event.”
The discovery is the first time scientists have been able to see both a disk of material falling into a black hole, known as an accretion disk, and a jet in a system of this kind.
ICRAR astrophysicist Dr James Miller-Jones compared the energy produced by the jets in this event to the entire energy output of the Sun over 10 million years.
He said it was likely all supermassive black holes swallowing stars launched jets but this discovery was made because the black hole is relatively close to Earth and was studied soon after it was first seen.
The black hole is only 300 million light years away from us and the team (led by Dr Sjoert van Velzen from The Johns Hopkins University in the USA) were able to make their first observations only three weeks after it was found.
“We’ve shown that it was just a question of looking at the right time and with enough sensitivity,” Dr Miller-Jones said.
“Then you can show that a jet exists right at the point you think it should.”
Dr Anderson began the research while working with the 4 PI SKY team at Oxford University but moved to Western Australia in September.
She said the event was first picked up by the All-sky Automated Survey for Supernovae (ASAS-SN), which is pronounced ‘assassin’ by astronomers, and followed up with the Arcminute Microkelvin Imager (AMI), a radio telescope, located near Cambridge.
“Hopefully with the increased sensitivity of future telescopes like the Square Kilometre Array we’ll be able to detect jets from other supermassive black holes of this type and discover even more about them,” Dr Anderson said.
For more information about the 4 PI SKY project visit http://www.4pisky.org
ICRAR is a joint venture between Curtin University and The University of Western Australia with support and funding from the State Government of Western Australia.
Original publication details:
‘A radio jet from the optical and X-ray bright stellar tidal disruption flare ASASSN-14li’ published in the journal Science on 26/11/2015. A copy of the paper is available upon request.
See the full article here .
ICRAR is an equal joint venture between Curtin University and The University of Western Australia with funding support from the State Government of Western Australia. The Centre’s headquarters are located at UWA, with research nodes at both UWA and the Curtin Institute for Radio Astronomy (CIRA).
ICRAR has strong support from the government of Australia and is working closely with industry and the astronomy community, including CSIRO and the Australian Telescope National Facility, iVEC, and the international SKA Project Office (SPO), based in the UK.
Playing a key role in the international Square Kilometre Array (SKA) project, the world’s biggest ground-based telescope array.
Attracting some of the world’s leading researchers in radio astronomy, who will also contribute to national and international scientific and technical programs for SKA and ASKAP.
Creating a collaborative environment for scientists and engineers to engage and work with industry to produce studies, prototypes and systems linked to the overall scientific success of the SKA, MWA and ASKAP.
Enhancing Australia’s position in the international SKA program by contributing to the development process for the SKA in scientific, technological and operational areas.
Promoting scientific, technical, commercial and educational opportunities through public outreach, educational material, training students and collaborative developments with national and international educational organisations.
Establishing and maintaining a pool of emerging and top-level scientists and technologists in the disciplines related to radio astronomy through appointments and training.
Making world-class contributions to SKA science, with emphasis on the signature science themes associated with surveys for neutral hydrogen and variable (transient) radio sources.
Making world-class contributions to SKA capability with respect to developments in the areas of Data Intensive Science and support for the Murchison Radio-astronomy Observatory.