Showing posts with label black holes. Show all posts
Showing posts with label black holes. Show all posts

Monday, December 14, 2009

Black Hole Found to Be Much Closer To Earth Than Previously Thought

An international team of astronomers has accurately measured the distance from Earth to a black hole for the first time. (Credit: Image courtesy of SRON Netherlands Institute for Space Research)

From Science Daily:

Science Daily (Dec. 14, 2009) — An international team of astronomers has accurately measured the distance from Earth to a black hole for the first time. Without needing to rely on mathematical models the astronomers came up with a distance of 7800 light years, much closer than had been assumed until now. The researchers achieved this breakthrough by measuring the radio emissions from the black hole and its associated dying star.

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Saturday, December 12, 2009

Super-Massive Black Holes Observed At The Center of Galaxies

UKIRT infrared images of the four target galaxies show them in near-infrared color, where the images at different infrared wavelengths are assigned to represent red, green and blue colors. Observations with the Keck Interferometer have resolved the inner structure of the bright nucleus in all the four galaxies. The inferred ring-like structure obtained for NGC 4151 at the top-left is depicted in the top-right panel. The ring radius is 0.13 light years, corresponding to an extremely small ~0.5 milli-arcsecond angular size on the sky. The distance to each galaxy is indicated in million light-years, together with the redshift (z) of each galaxy. (Credit: M. Kishimoto, MPIfR)

From Science Daily:

Science Daily (Dec. 11, 2009) — An international team of scientists has observed four super-massive black holes at the center of galaxies, which may provide new information on how these central black hole systems operate.

Their findings are published in December's first issue of the journal Astronomy and Astrophysics.

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Saturday, December 5, 2009

Mysterious "Strange" Stars May Rival Black Holes For Weirdness

In this top-down illustration of a black hole and its surrounding disk, gas spiraling toward the black hole piles up just outside it, creating a traffic jam. The traffic jam is closer in for smaller black holes, so X-rays are emitted on a shorter timescale. By NASA

From USA Today:

Think black holes are strange? Understandable considering these powerhouses of the universe (many times heavier than our sun) are collapsed stars with gravity so strong that even light cannot escape their grasp.

But maybe they're not "strange" enough, suggest some astrophysicists. "Stellar" black holes, ones only a few times heavier than the sun, may actually be something even weirder called a quark star, or "strange" star.

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Wednesday, December 2, 2009

Do Black Holes Build Their Own Galaxies?

From RedOrbit:

Which comes first, the supermassive black holes that frantically devour matter or the enormous galaxies where they reside? A brand new scenario has emerged from a recent set of outstanding observations of a black hole without a home: black holes may be “building” their own host galaxy. This could be the long-sought missing link to understanding why the masses of black holes are larger in galaxies that contain more stars.

The ‘chicken and egg’ question of whether a galaxy or its black hole comes first is one of the most debated subjects in astrophysics today,” says lead author David Elbaz. “Our study suggests that supermassive black holes can trigger the formation of stars, thus ‘building’ their own host galaxies. This link could also explain why galaxies hosting larger black holes have more stars.”

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Thursday, October 22, 2009

Lasers Simulate Black Hole In The Lab

An artist's impression of the swirling accretion disc surrounding a black hole.
Credit: David A. Aguilar/CfA


From Cosmos:

BRISBANE: The extreme conditions found around black holes and other very dense objects can be recreated in the laboratory with powerful lasers, physicists say.

The technique may allow them to validate the computer models they use to interpret black hole data collected by space-based telescopes, such as the Chandra X-Ray Observatory, according to a study published this week in Nature Physics.

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Monday, October 19, 2009

Artificial Black Hole Created in Chinese Lab

Pocket Black Hole The icons depict the shape of the energy-trapping ridges on the disc at the center and the edges via arXiv.org

From Popular Mechanics:

Just because most black holes are solar-system-sized maelstroms with reality-warping gravitational pulls doesn't mean you can't have one in your pocket! That's right, just in time for the holidays comes the pocket black hole. Designed by scientists at the Southeast University in Nanjing, China, this eight-and-a-half-inch-wide disk absorbs all the electromagnetic radiation you throw at it, with none of the pesky time dilation and Hawking radiation associated with the larger, interstellar versions.

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Friday, October 16, 2009

First Black Hole For Light Created On Earth

The full-wave simulation result when light is incident to the black hole
(Image: Qiang Cheng and Tie Jun Cui)


From New Scientist:

An electromagnetic "black holeMovie Camera" that sucks in surrounding light has been built for the first time.

The device, which works at microwave frequencies, may soon be extended to trap visible light, leading to an entirely new way of harvesting solar energy to generate electricity.

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Thursday, October 8, 2009

NASA Catches Two Black Holes Sucking Face

Black Hole Merger: Two pinpoints of light represent black holes in the center of this combined X-ray/optical image NASA/CXC/MIT/C.Canizares, M.Nowak/STScI

From Popular Science:

The Chandra X-ray Observatory helped discover two merging black holes a mere 3,000 light years apart

Colliding black holes may prove more interesting to scientists than the immovable object versus the unstoppable force. New data from NASA's Chandra X-ray Observatory has combined with optical images from Hubble to show off a merging black hole pair in all its glory.

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Tuesday, October 6, 2009

Black Holes Go 'Mano A Mano'

Credits: X-ray: NASA/CXC/MIT/C.Canizares, M.Nowak; Optical: NASA/STScI.

From Space Daily:

This image of NGC 6240 contains new X-ray data from Chandra (shown in red, orange, and yellow) that has been combined with an optical image from the Hubble Space Telescope originally released in 2008. In 2002, the discovery of two merging black holes was announced based on Chandra data in this galaxy.

The two black holes are a mere 3,000 light years apart and are seen as the bright point-like sources in the middle of the image.

Read more ....

Monday, October 5, 2009

Mammoth Black Holes Push Universe To Its Doom

Speaking of black holes, what could be stranger?
Beyond a black hole's gravitational border -- or event horizon -- neither matter nor light can escape. Astrophysicists think dying stars about three to 20 times the mass of the sun can form these strange objects. At the center of galaxies, black holes about 10,000 to 18 billion times heavier than the sun are thought to exist, enlarged by gobbling up gas, dust, stars and small black holes.
What about mid-sized types? Perhaps surprisingly, evidence is both scarce and questionable for their existence.
Caption: Conception of a black hole pulling gas off of a nearby star. Credit: ESA/NASA

From New Scientist:


THE mammoth black holes at the centre of most galaxies may be pushing the universe closer to its final fade-out. And it is all down to the raging disorder within those dark powerhouses.

Disorder is measured by a quantity called entropy, something which has been on the rise ever since the big bang. Chas Egan and Charles Lineweaver of the Australian National University in Canberra used the latest astrophysical data to calculate the total entropy of everything in the universe, from gas to gravitons. It turns out that supermassive black holes are by far the biggest contributors to the universe's entropy. Entropy reflects the number of possible arrangements of matter and energy in an object. The number of different configurations of matter a black hole could contain is staggering because its internal state is completely mysterious.

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Sunday, August 23, 2009

New Way To Reproduce A Black Hole?

Illustration of a binary black hole system. (Credit: NASA/JPL)

From Science Daily:

ScienceDaily (Aug. 22, 2009) — Despite their popularity in the science fiction genre, there is much to be learned about black holes, the mysterious regions in space once thought to be absent of light. In a paper published in the August 20 issue of Physical Review Letters, Dartmouth researchers propose a new way of creating a reproduction black hole in the laboratory on a much-tinier scale than their celestial counterparts.

The new method to create a tiny quantum sized black hole would allow researchers to better understand what physicist Stephen Hawking proposed more than 35 years ago: black holes are not totally void of activity; they emit photons, which is now known as Hawking radiation.

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Monday, August 17, 2009

Black Hole Parasites Explain Cosmic Flashes


From New Scientist:

SOME of the brightest flashes in the universe may be the result of black holes burrowing into stars and devouring them from inside.

The flashes are known as gamma-ray bursts because most of their energy is in the form of high-energy radiation, including gamma rays and X-rays. The longer flashes, lasting at least a few seconds, have long been thought to signal the deaths of massive stars that have run out of fuel, causing them to collapse to form black holes, unleashing powerful jets of radiation in the process.

Now an alternative explanation has been given new lease of life: a black hole may instead be an external attacker that dives into the belly of a massive star and consumes it.

Read more ....

Friday, July 24, 2009

Nasa Finds Monster Black Hole Sucking Up Gas, Dust And Stars At Centre Of Galaxy

The galaxy NGC-1097 with a monstrous black hole surrounded by a ring of stars at its centre
Photo: REUTERS / NASA


From The Telegraph:

Nasa has found a monster black hole 100 million times the mass of the Sun feeding off gas, dust and stars at the centre of a galaxy 50 million light-years away.

The star-ringed black hole forms the eye of a galaxy called NGC-1097 which was photographed by the US space agency's Spitzer Space Telescope in California.

A black hole is a region of space in which the gravitational pull is so powerful that nothing, including whole planets, can escape being sucked in if they come within its reach.

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Sunday, July 12, 2009

New Kind Of Astronomical Object Around Black Hole: Living Fossil Records 'Supermassive' Kick

This artist's conception shows a rogue black hole that has been kicked out from the center of two merging galaxies. The black hole is surrounded by a cluster of stars that were ripped from the galaxies. New calculations by David Merritt, from Rochester Institute of Technology, Jeremy Schnittman, from Johns Hopkins University, and Stefanie Komossa, from the Max-Planck-Institut for Extraterrestrial Physics in Germany suggest that hundreds of massive black holes, left over from the epoch of galaxy formation, are waiting to be detected in the nearby universe. (Credit: Space Telescope Science Institute)

From Science Daily:


ScienceDaily (July 10, 2009) — The tight cluster of stars surrounding a supermassive black hole after it has been violently kicked out of a galaxy represents a new kind of astronomical object and a fossil record of the kick.

A paper published in the July 10 issue of The Astrophysical Journal discusses the theoretical properties of “hypercompact stellar systems” and suggests that hundreds of these faint star clusters might be detected at optical wavelengths in our immediate cosmic environment. Some of these objects may already have been picked up in astronomical surveys, reports David Merritt, from Rochester Institute of Technology, Jeremy Schnittman, from Johns Hopkins University, and Stefanie Komossa, from the Max-Planck-Institut for Extraterrestrial Physics in Germany.

Read more ....

Thursday, July 2, 2009

New Class of Black Holes Discovered


From The Danger Room:

Only two sizes of black holes have ever been spotted: small and super-massive. Scientists have long speculated that an intermediate version must exist, but they’ve never been able to find one until now.

Astrophysicists identified what appears to be the first-ever medium-sized black hole, pictured in an artist’s rendition above, with a mass at least 500 times that of our Sun. Researchers from the Centre d’Etude Spatiale des Rayonnements in France detected the middling hole in a galaxy about 290 million light-years from Earth.

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Saturday, June 27, 2009

Black Holes On A Desktop


From The Economist:

Sound may offer a better way than light to test Stephen Hawking’s prediction that black holes emit radiation.

WHEN the Large Hadron Collider, a giant particle accelerator near Geneva, was switched on last September, the press was full of scare stories about the risk of it producing a tiny black hole that would, despite its minuscule size, quickly swallow the Earth. In fact, the first test runs could never have made such an object. And, just over a week later, the LHC broke and has not yet been repaired. But it is true that one of the things its operators would like to create, if and when they get it going again, are miniature versions of those fabled astronomical objects whose intense gravity means no light can escape them.

Read more .....

Sunday, June 14, 2009

Sonic Disruptions Create Artificial Black Hole

None More Black : Erlenmeyer fask. Check. Beaker. Check. Black hole. Ummm... courtesy of Wikimedia Commons

From Popsci.com:

After 30 years of trying, scientists create first-ever acoustic black hole.

Stephen Hawking once theorized that black holes would emit a stream of electromagnetic radiation named, what else, Hawking Radiation. However, in the 35 years since Hawking made his prediction, no one has observed the phenomena. Now, a team of Israeli scientists are working on a way to make their own Hawking Radiation by creating an artificial black hole in their lab.

Read more ....

Wednesday, June 10, 2009

Galactic Black Holes May Be More Massive Than Thought

Illustrated is a new understanding of the relationship between the mass of a galaxy’s central black hole and the mass of its central bulge of stars. A new model suggests revising how this relationship is defined, at least for black holes in the most massive galaxies. Credit: Tim Jones/Univ. of Texas at Austin after K. Cordes and S. Brown/STScI

From Science News:

Predictions and observations could resolve seeming mismatch between close and distant giants

Astronomers report that some of the biggest supermassive black holes in nearby galaxies are at least twice and possibly four times as heavy as previously estimated. The findings come from new simulations by two independent teams of researchers, as well as new observations of stars whipping around a handful of supermassive black holes at the centers of massive galaxies no more than a few hundred million light-years from Earth.

Read more ....

Monday, June 8, 2009

A Real Whopper: Black Hole Is Most Massive Known

(Image from Discovery.com)

From Yahoo News/Space.com:

PASADENA, CALIF. — The most massive black hole yet weighed lurks at the heart of the relatively nearby giant galaxy M87.

The supermassive black hole is two to three times heftier than previously thought, a new model showed, weighing in at a whopping 6.4 billion times the mass of the sun. The new measure suggests that other black holes in nearby large galaxies could also be much heftier than current measurements suggest, and it could help astronomers solve a longstanding puzzle about galaxy development.

"We did not expect it at all," said team member Karl Gebhardt of the University of Texas at Austin.

The discovery was announced here today at the 214th meeting of the American Astronomical Society.

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Wednesday, May 20, 2009

Preparing To Peer Into A Black Hole

The Sagittarius A* supermassive black hole, as seen by the Chandra X-ray Observatory. Nobody has yet seen the black hole directly (Image: NASA)

From New Scientist:

LIKE a giant pale blue eye, the Earth stares at the centre of our galaxy. Through the glare and the fog it is trying to catch a glimpse of an indistinct something 30,000 light years away. Over there, within the sparkling starscape of the galaxy's core... no, not those giant suns or those colliding gas clouds; not the gamma-ray glow of annihilating antimatter. No, right there in the very centre, inside that swirling nebula of doomed matter, could that be just a hint of a shadow?

The shadow we're straining to see is that of a monstrous black hole, a place where gravity rules supreme, swallowing light and stretching the fabric of space to breaking point. Black holes are perhaps the most outrageous prediction of science, and even though we can paint fine theoretical pictures of them and point to evidence for many objects that seem to be black hole-ish, nobody has ever actually seen one.

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