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Against All Odds: Astronomers Baffled By Discovery Of Rare Quasar Quartet


Image: Arrigoni-Battaia & Hennawi / MPIA

Image: Arrigoni-Battaia & Hennawi / MPIA

Using the W.M. Keck observatory in Hawaii, a group of astronomers led by Joseph Hennawi of the Max Planck Institute for Astronomy have discovered the first quadruple quasar: four rare active black holes situated in close proximity to one another. The quartet resides in one of the most massive structures ever discovered in the distant universe, and is surrounded by a giant nebula of cool dense gas. Either the discovery is a one-in-ten-million coincidence, or cosmologists need to rethink their models of quasar evolution and the formation of the most massive cosmic structures. The results are being published in the May 15, 2015 edition of the journal Science.

Hitting the jackpot is one thing, but if you hit the jackpot four times in a row you might wonder if the odds were somehow stacked in your favor. A group of astronomers led by Joseph Hennawi of the Max Planck Institute for Astronomy have found themselves in exactly this situation. They discovered the first known quasar quartet: four quasars, each one a rare object in its own right, in close physical proximity to each other.

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RX J1131-1231: Chandra & XMM-Newton Provide Direct Measurement Of Distant Black Hole’s Spin


Credit: X-ray: NASA/CXC/Univ of Michigan/R.C.Reis et al; Optical: NASA/STScI

Credit: X-ray: NASA/CXC/Univ of Michigan/R.C.Reis et al; Optical: NASA/STScI

Multiple images of a distant quasar are visible in this combined view from NASA’s Chandra X-ray Observatory and the Hubble Space Telescope. The Chandra data, along with data from ESA’s XMM-Newton, were used to directly measure the spin of the supermassive black hole powering this quasar. This is the most distant black hole where such a measurement has been made, as reported in our press release.

Gravitational lensing by an intervening elliptical galaxy has created four different images of the quasar, shown by the Chandra data in pink. Such lensing, first predicted by Einstein, offers a rare opportunity to study regions close to the black hole in distant quasars, by acting as a natural telescope and magnifying the light from these sources. The Hubble data in red, green and blue shows the elliptical galaxy in the middle of the image, along with other galaxies in the field.

The quasar is known as RX J1131-1231 (RX J1131 for short), located about 6 billion light years from Earth. Using the gravitational lens, a high quality X-ray spectrum – that is, the amount of X-rays seen at different energies – of RX J1131 was obtained.

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New Fast And Furious Black Hole Found

February 28, 2014 Leave a comment

Image Credits: M83 - NASA, ESA and the Hubble Heritage Team (WFC3/UVIS, STScI-PRC14-04a).MQ1

Image Credits: M83 – NASA, ESA and the Hubble Heritage Team (WFC3/UVIS, STScI-PRC14-04a).MQ1

A team of Australian and American astronomers have been studying nearby galaxy M83 and have found a new superpowered small black hole, named MQ1, the first object of its kind to be studied in this much detail.

Astronomers have found a few compact objects that are as powerful as MQ1, but have not been able to work out the size of the black hole contained within them until now.

The team observed the MQ1 system with multiple telescopes and discovered that it is a standard-sized small black hole, rather than a slightly bigger version that was theorised to account for all its power.

Curtin University senior research fellow Dr Roberto Soria, who is part of the International Centre for Radio Astronomy Research (ICRAR) and led the team investigating MQ1, said it was important to understand how stars were formed, how they evolved and how they died, within a spiral shaped galaxy like M83.

“MQ1 is classed as a microquasar – a black hole surrounded by a bubble of hot gas, which is heated by two jets just outside the black hole, powerfully shooting out energy in opposite directions, acting like cosmic sandblasters pushing out on the surrounding gas,” Dr Soria said.

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New Data On The Composition Of Relativistic Jets From Black Holes

November 21, 2013 Leave a comment

Artist impression. Image: Riccardo Lanfranchi

Artist impression. Image: Riccardo Lanfranchi

It is known that black holes launch relativistic jets both in stellar-mass binary systems and at the centres of galaxies, in the so-called ‘quasars’. Although jets have been studied for decades, their composition has remained uncertain. Now, a work, published on Nature and led by researchers from the University of Barcelona, the German headquarters of the European Southern Observatory (ESO) and Curtin University (Australia), presents the detection of atomic nuclei in the relativistic jets from the black hole binary system 4U 1630-47.

“In this work, we have found the composition of relativistic jets launched from around black holes; however, more studies are needed to understand if results can be extrapolated to other relativistic jet sources”, explains Simone Migliari, from the Institute of Sciences of the Cosmos of the UB (ICCUB). According to the researcher, the research proves that relativistic jets might be ‘heavy jets’ containing atomic nuclei, rather than ‘light jets’ consisting of electrons and positrons only”. “The finding —he adds— implies that ‘heavy jets’ carry away significantly more energy from the black hole than ‘lighter’ ones”.

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New Type Of Black-Hole Quasar Discovered

November 13, 2013 Leave a comment

Like our Milky Way, every known large galaxy has at its center a supermassive black hole, some of which are surrounded by a super-bright disk of hot gas called a quasar — but now a research team that includes Penn State astronomers has discovered a surprising new class of quasars in distant galaxies that even the most current theories had not predicted.

“The gas in this new type of quasar is moving in two directions: some is moving toward Earth but most of it is moving at high velocities away from us, possibly toward the quasar’s black hole,” said study co-author Niel Brandt, Distinguished Professor of Astronomy and Astrophysics at Penn State University. “Just as you can use the Doppler shift for sound to tell if an airplane is moving away from you or toward you, we used the Doppler shift for light to tell whether the gas in these quasars is moving away from Earth or toward these distant black holes, which have a mass from millions to billions of times that of the Sun.” Brandt explained. Matter around these black holes forms a quasar disc that is bigger than Earth’s orbit around the Sun and hotter than the surface of the Sun. These quasars generate enough light to be seen across the observable universe.

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Astronomers Observe Distant Galaxy Powered By Primordial Cosmic Fuel

October 4, 2013 Leave a comment

CREDIT: MPIA (G. STINSON / A. V. MACCIÒ)

CREDIT: MPIA (G. STINSON / A. V. MACCIÒ)

Astronomers have detected cold streams of primordial hydrogen, vestigial matter left over from the Big Bang, fueling a distant star-forming galaxy in the early Universe. Profuse flows of gas onto galaxies are believed to be crucial for explaining an era 10 billion years ago, when galaxies were copiously forming stars. To make this discovery, the astronomers – led by Neil Crighton of the Max Planck Institute for Astronomy and Swinburne University – made use of a cosmic coincidence: a bright, distant quasar acting as a “cosmic lighthouse” illuminates the gas flow from behind. The results were published October 2 in the Astrophysical Journal Letters.

The systematic survey of absorption systems comprises observations with the Large Binocular Telescope and from data taken with the W. M. Keck Observatory’s HIRES echelle spectrograph installed on the 10 meter Keck I telescope on the summit of Mauna Kea, Hawaii. The foreground galaxy was discovered by Charles Steidel, Gwen Rudie (California Institute of Technology) and collaborators using the Keck Observatory’s LRIS spectrograph on the same telescope.

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Quasar Observed In 6 Separate Light Reflections


Quasars are active black holes – primarily from the early universe. Using a special method where you observe light that has been bent by gravity on its way through the universe, a group of physics students from the Niels Bohr Institute have observed a quasar whose light has been deflected and reflected in six separate images. This is the first time a quasar has been observed with so many light reflections. The results are published in the scientific journal, Astrophysical Journal.

“We had three hours to observe and already after one hour we had the first spectrum. It was a new experience for us, but we could see immediately that it was a quasar. A typical characteristic of a quasar is that the light has broad emission lines from gas close to the black hole. We were very excited and moved on to the other ‘candidates’ from observation and later that night we found yet another light reflection of the quasar,” explains Thejs Brinckmann, one of the astrophysics students working on the project. The other students in the group were Mikkel Kristensen, Mikkel Lindholmer and Anders Nielsen.

Full Story: http://www.nbi.ku.dk/english/news/news13/quasar-observed-in-6-separate-light-reflections/