Combining observations done with ESO's Very Large Telescope and NASA's Chandra X-ray telescope, astronomers have uncovered the most powerful pair of jets ever seen from a stellar black hole. The black hole blows a huge bubble of hot gas, 1,000 light-years across or twice as large and tens of times more powerful than the other such microquasars. The stellar black hole belongs to a binary system as pictured in this artist's impression. Credit: ESO/L. Calçada
A relatively small black hole is producing tremendously powerful jets while creating a huge bubble of hot gas. Both the jets and the bubble are the largest ever seen, meaning this mini black hole is a powerhouse. But the most unusual feature of this remarkable black hole is not its energy output, but how it is emitting energy.
"The energy output is impressive, but is comparable with the X-ray luminosity of so-called Ultraluminous X-ray sources," said Manfred Pakull, the lead author of a new paper published today in Nature. "The notion that powerhouses exist that generate most of their energy in the form of jets (kinetic energy) and not as radiation (photons) is rather new."
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Radio Observations Provide New Explanation for Hanny's Voorwerp
The green 'blob' is Hanny's Voorwerp. Credit: Dan Herbert, Peter Smith, Matt Jarvis, Galaxy Zoo Team, Isaac Newton Telescope
Is Hanny's Voorwerp the result of a "light echo" of a violent event that happened long ago or perhaps is this mystifying blob of glowing gas being fueled by an ongoing, and current phenomenon? A just-released paper about the Voorwerp offers a new explanation for this perplexing, seemingly one-of-a-kind object in the constellation of Leo Minor. If you haven't heard the remarkable story, the object was discovered in 2007 by Dutch school teacher Hanny Van Arkel while she was classifying galaxies for the Galaxy Zoo online citizen science project. Until now, the working hypothesis for the explanation of this unusual object was that we might be seeing the "light echo" of a quasar outburst event that occurred millions of years ago. But new radio observations reveal that instead, a black hole in that same nearby galaxy might be producing a radio jet, shooting a thin beam directly at this cloud of gas, causing it to light up.
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Retro Black Holes Are More Powerful
This artist's concept shows a galaxy with a supermassive black hole at its core. The black hole is shooting out jets of radio waves.Image credit: NASA/JPL-Caltech
Black holes seem to defy our comprehension and be contrary to conventional understanding. So perhaps it is not entirely surprising to find that supermassive black holes which have a retrograde or backwards spin might be more powerful and produce more ferocious jets of gas. While this new finding goes against what astronomers had thought for decades, it also helps solve a mystery why some black holes have no jets at all.
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Andromeda's Unstable Black Hole
The Andromeda galaxy as seen in optical light, and Chandra's X-ray vision of the changing supermassive black hole in Andromeda's heart. Image Credit: X-Ray NASA/CXC/SAO/Li et al.), Optical (DSS)
The Andromeda galaxy, the closest spiral galaxy to our own Milky Way, has a supermassive black hole at the center of it much like other galaxies. Because of its proximity to us, Andromeda – or M31 – is an excellent place to study just how the supermassive black holes in the centers of galaxies consume material to grow, and interact gravitationally with the surrounding material.
Over the course of the last ten years, NASA's Chandra X-Ray observatory has monitored closely the supermassive black hole at Andromeda's heart. This long-term data set gives astronomers a very nuanced picture of just how these monstrous black holes change over time. Zhiyuan Li of the Harvard-Smithsonian Center for Astrophysics (CfA) presented results of this decade-long observation of the black hole at the 216th American Astronomical Society meeting in Miami, Florida this week. Read more…
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Black Hole in M87 Wanders using Jetpack
Hubble Space Telescope Images of M87. At right, a large scale image taken with the Wide-Field/Planetary Camera-2 from 1998. The zoom-in images on the left are of the central portion of M87. HST-1 is a knot in the jet from the SMBH. (NASA and the Hubble Heritage Team (STScI/AURA), J. A. Biretta, W. B. Sparks, F. D. Macchetto, E. S. Perlman)
The elliptical galaxy M87 is known for a jet of radiation that is streaming from the supermassive black hole (SMBH) that the galaxy houses. This jet, which is visible through large-aperture telescopes, may have functioned as a black hole 'jetpack', moving the SMBH from the center of mass of the galaxy – where most SMBHs are thought to reside.
Observations taken with the Hubble Space Telescope by a collaboration of astronomy researchers at Rochester Institute of Technology, Florida Institute of Technology and University of Sussex in the United Kingdom show the SMBH in M87 to be displaced from the center of the galaxy by as much as 7 parsecs (22.82 light years). This contradicts the long-held theory that supermassive black holes reside at the center of the galaxies they inhabit, and may give astronomers one way to trace the history of galaxies that have grown through merging. Read more…
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Galaxy Mergers Make Black Holes 'Light Up'
Only about 1% of supermassive black holes emit large amounts of energy, and astronomers have wondered for decades why so few exhibit this behavior. Data from Swift satellite, which normally studies gamma ray bursts, has allowed scientists to confirm that black holes "light up" when galaxies collide, and the data may offer insight into the future behavior of the black hole in our own Milky Way galaxy.
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Black Hole Gets Kicked Out of Galaxy
A Hubble Space Telescope image of the galaxy studied by Marianne Heida. The white circle marks the centre of the galaxy and the red circle marks the position of the suspected offset black hole. Image: STScI / NASA
Supermassive black holes are thought to lie at the center of most large galaxies. But off in a distant remote galaxy, astronomers have possibly found a giant black hole that appears to be in the process of being expelled from the galaxy at high speed. This newly-discovered object was found by Marianne Heida, a student at Utrecht University in the Netherlands, and confirmed by an international team of astronomers who say the black hole was likely kicked out of its galaxy as a result of the merger of two smaller black holes.
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Is Our Universe Inside Another Larger Universe?
Wormhole. Credit: Internet Encyclopedia of Science
A wormhole is a hypothetical "tunnel" connecting two different points in spacetime, and in theory, at each end of the wormhole there could be two universes. Theoretical physicist Nikodem Poplawski from Indiana University has taken things a step further by proposing that perhaps our universe could be located within the interior of a wormhole which itself is part of a black hole that lies within a much larger universe.
Whoa. I may have just lost my bearings.
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Andromeda's Double Nucleus – Explained at Last?
In 1993, the Hubble Space Telescope snapped a close-up of the nucleus of the Andromeda galaxy, M31, and found that it is double.
In the 15+ years since, dozens of papers have been written about it, with titles like The stellar population of the decoupled nucleus in M 31, Accretion Processes in the Nucleus of M31, and The Origin of the Young Stars in the Nucleus of M31.
And now there's a paper which seems, at last, to explain the observations; the cause is, apparently, a complex interplay of gravity, angular momentum, and star formation.
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Astronomers Find Black Holes Do Not Absorb Dark Matter
Artist’s schematic impression of the distortion of spacetime by a supermassive black hole at the centre of a galaxy. The black hole will swallow dark matter at a rate which depends on its mass and on the amount of dark matter around it. Image: Felipe Esquivel Reed.
There's the common notion that black holes suck in everything in the nearby vicinity by exerting a strong gravitational influence on the matter, energy, and space surrounding them. But astronomers have found that the dark matter around black holes might be a different story. Somehow dark matter resists 'assimilation' into a black hole.
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Spitzer Spies Earliest Black Holes
This artist's conception illustrates one of the most primitive supermassive black holes known (central black dot) at the core of a young, star-rich galaxy. Image credit: NASA/JPL-Caltech
The Spitzer Space Telescope has found what appear to be two of the earliest and most primitive supermassive black holes known. "We have found what are likely first-generation quasars, born in a dust-free medium and at the earliest stages of evolution," said Linhua Jiang of the University of Arizona, Tucson, lead author of a paper published this week in Nature.
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World-wide Campaign Sheds New Light on Nature's "LHC"
Recent observations of blazar jets require researchers to look deeper into whether current theories about jet formation and motion require refinement. This simulation, courtesy of Jonathan McKinney (KIPAC), shows a black hole pulling in nearby matter (yellow) and spraying energy back out into the universe in a jet (blue and red) that is held together by magnetic field lines (green).
In a manner somewhat like the formation of an alliance to defeat Darth Vader's Death Star, more than a decade ago astronomers formed the Whole Earth Blazar Telescope consortium to understand Nature's Death Ray Gun (a.k.a. blazars). And contrary to its at-death's-door sounding name, the GASP has proved crucial to unraveling the secrets of how Nature's "LHC" works.
"As the universe's biggest accelerators, blazar jets are important to understand," said Kavli Institute for Particle Astrophysics and Cosmology (KIPAC) Research Fellow Masaaki Hayashida, corresponding author on the recent paper presenting the new results with KIPAC Astrophysicist Greg Madejski. "But how they are produced and how they are structured is not well understood. We're still looking to understand the basics."
Blazars dominate the gamma-ray sky, discrete spots on the dark backdrop of the universe. As nearby matter falls into the supermassive black hole at the center of a blazar, "feeding" the black hole, it sprays some of this energy back out into the universe as a jet of particles.
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Supermassive Black Holes Spinning Backwards Create Death Ray Jets?
Centaurus A. Image credit: NASA
Why do some of the supermassive black holes in active galactic nuclei create back-to-back jets that can vaporize entire solar systems, while others have no jets at all?
Dan Evans, a postdoctoral researcher at MIT Kavli Institute for Astrophysics and Space Research (MKI) thinks he knows why; it's because the jet-producing supermassive black holes are spinning backwards, relative to their accretion disks.
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Can a Really, Really Fast Spacecraft Turn Into A Black Hole?
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Caught in the Act! Merging Galaxies Create a Binary Quasar
SDSS J1254+0846 in x-rays (blue), and optical (yellow)
(Credits: X-ray: NASA/CXC/SAO/Green et al Optical: Carnegie Obs/Magellan/Baade Telescope/Mulchaey et al)
Excellent teamwork by astronomers working in two different wavebands – x-ray and optical – has led to the discovery of a binary quasar being created by a pair of merging galaxies.
"This is really the first case in which you see two separate galaxies, both with quasars, that are clearly interacting," says Carnegie astronomer John Mulchaey who made observations crucial to understanding the galaxy merger.
"The model verifies the merger origin for this binary quasar system," Thomas Cox, now a fellow at the Carnegie Observatories, says, referring to computer simulations of the merging galaxies he produced. When Cox's model galaxies merged, they showed features remarkably similar to what Mulchaey observed in the Magellan images. "It also hints that this kind of galaxy interaction is a key component of the growth of black holes and production of quasars throughout our universe," Cox added.
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