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Astronomers ‘Unscramble’ Einstein Ring To Reveal Most Detailed View Ever Of Star Formation In The Distant Universe


Credit: ALMA (NRAO/ESO/NAOJ)/Y. Tamura (The University of Tokyo)/Mark Swinbank (Durham University)

Credit: ALMA (NRAO/ESO/NAOJ)/Y. Tamura (The University of Tokyo)/Mark Swinbank (Durham University)

ALMA’s Long Baseline Campaign produced spectacular images of the distant, gravitationally lensed galaxy called HATLAS J090311.6+003906, otherwise known as SDP.81. New analyses of these images reveal details never before seen in a galaxy so remote, including phenomenally massive yet concentrated clumps of star-forming material.

The ALMA observations of SDP.81, made at the end of 2014, were enabled by a cosmic effect known as gravitational lensing. A large galaxy nestled between SDP.81 and ALMA is acting as a lens, magnifying the more distant galaxy’s light and warping it into a near-perfect example of a phenomenon known as an Einstein Ring.

In the months following these observations, at least seven groups of scientists have independently analyzed the ALMA data on SDP.81. This flurry of research papers has divulged unprecedented information about the galaxy, including details about its structure, contents, motion, and other physical characteristics.

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Hubble Video Shows Shock Collision Inside Black Hole Jet


Credit: NASA, ESA, and E. Meyer (STScI)

Credit: NASA, ESA, and E. Meyer (STScI)

When you’re blasting though space at more than 98 percent of the speed of light, you may need driver’s insurance. Astronomers have discovered for the first time a rear-end collision between two high-speed knots of ejected matter from a super-massive black hole. This discovery was made while piecing together a time-lapse movie of a plasma jet blasted from a supermassive black hole inside a galaxy located 260 million light-years from Earth.

he finding offers new insights into the behavior of “light-saber-like” jets that are so energized that they appear to zoom out of black holes at speeds several times the speed of light. This “superluminal” motion is an optical illusion due to the very fast real speed of the plasma, which is close to the universal maximum of the speed of light.

Such extragalactic jets are not well understood. They appear to transport energetic plasma in a confined beam from the central black hole of the host galaxy. The new analysis suggests that shocks produced by collisions within the jet further accelerate particles and brighten the regions of colliding material.

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NASA’s WISE Spacecraft Discovers Most Luminous Galaxy In Universe

May 21, 2015 1 comment

Artist's concept. Image credit: N/A

Artist’s concept. Image credit: N/A

A remote galaxy shining with the light of more than 300 trillion suns has been discovered using data from NASA’s Wide-field Infrared Survey Explorer (WISE). The galaxy is the most luminous galaxy found to date and belongs to a new class of objects recently discovered by WISE — extremely luminous infrared galaxies, or ELIRGs.

“We are looking at a very intense phase of galaxy evolution,” said Chao-Wei Tsai of NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, lead author of a new report appearing in the May 22 issue of The Astrophysical Journal. “This dazzling light may be from the main growth spurt of the galaxy’s black hole.

The brilliant galaxy, known as WISE J224607.57-052635.0, may have a behemoth black hole at its belly, gorging itself on gas. Supermassive black holes draw gas and matter into a disk around them, heating the disk to roaring temperatures of millions of degrees and blasting out high-energy, visible, ultraviolet, and X-ray light. The light is blocked by surrounding cocoons of dust. As the dust heats up, it radiates infrared light.

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SGR 1745-2900: Magnetar Near Supermassive Black Hole Delivers Surprises


Credit: NASA/CXC/INAF/F.Coti Zelati et al

Credit: NASA/CXC/INAF/F.Coti Zelati et al

In 2013, astronomers announced they had discovered a magnetar exceptionally close to the supermassive black hole at the center of the Milky Way using a suite of space-borne telescopes including NASA’s Chandra X-ray Observatory.

Magnetars are dense, collapsed stars (called “neutron stars”) that possess enormously powerful magnetic fields. At a distance that could be as small as 0.3 light years (or about 2 trillion miles) from the 4-million-solar mass black hole in the center of our Milky Way galaxy, the magnetar is by far the closest neutron star to a supermassive black hole ever discovered and is likely in its gravitational grip.

A new study uses long-term monitoring observations to reveal that the amount of X-rays from SGR 1745-2900 is dropping more slowly than other previously observed magnetars, and its surface is hotter than expected.

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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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Widespread Winds And Feedback From Supermassive Black Holes

February 20, 2015 1 comment

Astronomers have discovered that the winds from supermassive black holes at the centre of galaxies blow outward in all directions, a suspected phenomenon that had been difficult to prove before now.

These new findings, by an international team of astrophysicists, were made possible by simultaneous observations of the luminous quasar PDS 456 with ESA’s XMM-Newton and NASA’s NuSTAR X-ray telescopes, and support the picture of black holes having a significant impact on star formation in their host galaxies.

At the core of every massive galaxy in the Universe, including our own Milky Way, sits a supermassive black hole, with a mass some millions or billions of times that of our Sun. Some of these black holes are active, meaning that their intense gravitational pull causes matter to spiral inward, and at the same time part of that matter is cast away through powerful winds.

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NASA, ESA Telescopes Give Shape To Furious Black Hole Winds

February 19, 2015 Leave a comment

Image credit: NASA/JPL-Caltech

Image credit: NASA/JPL-Caltech

NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) and ESA’s (European Space Agency) XMM-Newton telescope are showing that fierce winds from a supermassive black hole blow outward in all directions — a phenomenon that had been suspected, but difficult to prove until now.

This discovery has given astronomers their first opportunity to measure the strength of these ultra-fast winds and prove they are powerful enough to inhibit the host galaxy’s ability to make new stars

“We know black holes in the centers of galaxies can feed on matter, and this process can produce winds. This is thought to regulate the growth of the galaxies,” said Fiona Harrison of the California Institute of Technology (Caltech) in Pasadena, California. Harrison is the principal investigator of NuSTAR and a co-author on a new paper about these results appearing in the journal Science. “Knowing the speed, shape and size of the winds, we can now figure out how powerful they are.”

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Unusual Light Signal Yields Clues About Elusive Black Hole Merger

January 8, 2015 Leave a comment

Credit: Santiago Lombeyda/Caltech Center for Data-Driven Discovery

Credit: Santiago Lombeyda/Caltech Center for Data-Driven Discovery

The central regions of many glittering galaxies, our own Milky Way included, harbor cores of impenetrable darkness—black holes with masses equivalent to millions, or even billions, of suns. What is more, these supermassive black holes and their host galaxies appear to develop together, or “co-evolve.” Theory predicts that as galaxies collide and merge, growing ever more massive, so too do their dark hearts.

Black holes by themselves are impossible to see, but their gravity can pull in surrounding gas to form a swirling band of material called an accretion disk. The spinning particles are accelerated to tremendous speeds and release vast amounts of energy in the form of heat and powerful X-rays and gamma rays. When this process happens to a supermassive black hole, the result is a quasar—an extremely luminous object that outshines all of the stars in its host galaxy and that is visible from across the universe. “Quasars are valuable probes of the evolution of galaxies and their central black holes,” says George Djorgovski, professor of astronomy and director of the Center for Data-Driven Discovery at Caltech.

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‘Perfect Storm’ Quenching Star Formation Around A Supermassive Black Hole

December 17, 2014 Leave a comment

A combined Hubble Space Telescope / ALMA image of NGC 1266. Credit: NASA/ESA Hubble; ALMA (NRAO/ESO/NAOJ)

A combined Hubble Space Telescope / ALMA image of NGC 1266. Credit: NASA/ESA Hubble; ALMA (NRAO/ESO/NAOJ)

High-energy jets powered by supermassive black holes can blast away a galaxy’s star-forming fuel, resulting in so-called “red and dead” galaxies: those brimming with ancient red stars yet containing little or no hydrogen gas to create new ones.

Now astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have discovered that black holes don’t have to be nearly so powerful to shut down star formation. By observing the dust and gas at the center of NGC 1266, a nearby lenticular galaxy with a relatively modest central black hole, the astronomers have detected a “perfect storm” of turbulence that is squelching star formation in a region that would otherwise be an ideal star factory.

This turbulence is stirred up by jets from the galaxy’s central black hole slamming into an incredibly dense envelope of gas. This dense region, which may be the result of a recent merger with another smaller galaxy, blocks nearly 98 percent of material propelled by the jets from escaping the galactic center.

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UCLA Astronomers Solve Puzzle About Bizarre Object At The Center Of Our Galaxy

November 3, 2014 Leave a comment

For years, astronomers have been puzzled by a bizarre object in the center of the Milky Way that was believed to be a hydrogen gas cloud headed toward our galaxy’s enormous black hole.

Having studied it during its closest approach to the black hole this summer, UCLA astronomers believe that they have solved the riddle of the object widely known as G2.

A team led by Andrea Ghez, professor of physics and astronomy in the UCLA College, determined that G2 is most likely a pair of binary stars that had been orbiting the black hole in tandem and merged together into an extremely large star, cloaked in gas and dust — its movements choreographed by the black hole’s powerful gravitational field. The research is published today in the journal Astrophysical Journal Letters.

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