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Latest Quasi-periodic oscillations Stories

X-ray Signal Detected During Black Hole's Destruction Of Passing Star
2012-08-03 15:48:00

[Watch Video] Lee Rannals for redOrbit.com — Your Universe Online Astronomers have identified an X-ray signal that followed an observation made last year of a quiescent black hole in a distant galaxy. The black hole discovered by the team last year was seen erupting after shredding and consuming a passing star. Astronomers then witnessed days following the observation a distinctive X-ray signal that comes from matter on the verge of falling into the black hole. This...

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2008-09-17 14:20:00

XMM-Newton has uncovered a well-tuned periodic signal from a super-massive black hole lodged at the centre of a galaxy, ending a long quest for such an object. The discovery provides scientists with a clearer picture on black hole accretion processes and an excellent tool to study active galactic nuclei (AGNs). These periodic signals originating from the black hole are emitted in X-rays, which are blocked out by the Earth's atmosphere. So the team used data from ESA's orbiting X-ray...

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2008-04-30 17:35:00

Using observations from NASA's Rossi X-ray Timing Explorer (RXTE), an international team of astronomers has discovered a timing mechanism that allows them to predict exactly when a superdense star will unleash incredibly powerful explosions. "We found a clock that ticks slower and slower, and when it slows down too much, boom! The bomb explodes," says lead author Diego Altamirano of the University of Amsterdam in the Netherlands. The bursts occur on a neutron star, which is the collapsed...

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2008-04-01 16:30:00

Using a new technique, two NASA scientists have identified the lightest known black hole. With a mass only about 3.8 times greater than our Sun and a diameter of only 15 miles, the black hole lies very close to the minimum size predicted for black holes that originate from dying stars."This black hole is really pushing the limits. For many years astronomers have wanted to know the smallest possible size of a black hole, and this little guy is a big step toward answering that question," says...

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2008-01-10 18:05:00

It's well known that black holes can slow time to a crawl and tidally stretch large objects into spaghetti-like strands. But according to new theoretical research from two NASA astrophysicists, the wrenching gravity just outside the outer boundary of a black hole can produce yet another bizarre effect: light echoes. "The light echoes come about because of the severe warping of spacetime predicted by Einstein," says Keigo Fukumura of NASA's Goddard Space Flight Center in Greenbelt, Md. "If...

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2007-05-16 12:15:00

ESA's XMM-Newton has helped to find evidence for the existence of controversial Intermediate Mass Black Holes. Scientists used a new, recently proven method for determining the mass of black holes. Nikolai Shaposhnikov and Lev Titarchuk, at NASA's Goddard Space Flight Center (GSFC), have used the technique to determine the mass of the black hole, Cygnus X-1, located in the constellation Cygnus (the Swan) approximately 10 000 light years away in our Galaxy, the Milky Way. The elegant...

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2006-01-11 07:15:00

MIT -- MIT scientists and colleagues have found a black hole that has chiseled a remarkably stable indentation in the fabric of space and time, like a dimple in one's favorite spot on the sofa. The finding may help scientists measure a black hole's mass and how it spins, two long-sought measurements, by virtue of the extent of this indentation. Using NASA's Rossi X-ray Timing Explorer, the team saw identical patterns in the X-ray light emitted near the black hole nine years apart, as captured...

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2005-03-22 10:25:00

NASA -- Peculiar outbursts of X-rays coming from a black hole have provided evidence that it has a mass of about 10,000 Suns, which would place it in a possible new class of black holes. The timing and regularity of these outbursts, observed with NASA's Chandra X-ray Observatory, make the object one of the best candidates yet for a so-called intermediate-mass black hole.Scientists have strong evidence for the existence of stellar black holes that are about 10 times as massive as the Sun. They...

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2005-01-11 14:20:00

San Diego, CA -- Astronomers Jon Miller (Harvard-Smithsonian Center for Astrophysics) and Jeroen Homan (MIT) have seen evidence of hot iron gas riding a ripple in spacetime around a black hole. This spacetime wave, if confirmed, would represent a new phenomenon that goes beyond Einstein's general relativity. These observations confirm one important theory about how a black hole's extreme gravity can stretch light. The data also paint an intriguing image of how a spinning black hole can drag...


Latest Quasi-periodic oscillations Reference Libraries

6_75b9b62fd255ef9e172fae83099783a52
2004-10-19 04:45:41

Accretion Disk -- An accretion disk is a structure formed by material falling into a gravitational source. Conservation of angular momentum requires that, as a large cloud of material collapses inward, any small rotation it may have will increase. Centrifugal force causes the rotating cloud to collapse into a disk, and tidal effects will tend to align this disk's rotation with the rotation of the gravitational source in the center. Friction between the particles of the disk generates heat...

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