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Gravitational Lensing Provides Rare Glimpse Into Interiors of Black Holes Article written: 17 Aug , 2017 by Matt Williams The observable Universe is an extremely big place, measuring an estimated 91 billion light-years in diameter. As a result, astronomers are forced to rely on powerful instruments to see faraway objects. But even these are sometimes limited, and must be paired with a technique known as gravitational lensing. This involves relying on a large distribution of matter (a galaxy or star) to magnify the light coming from a distant object.Using this technique, an international team led by researchers from the California...

The Laser Interferometer Gravitational-wave Observatory (LIGO) continues to make waves within the physics community. On June 1, they published their third gravitational wave detection from an observation in early January 2017. This new detection may help vet previously established theories of how these massive mergers behave, and has already provided a new round of observational data to push forward this new kind of astronomy. The confirmed results, published in Physical Review Letters, tell a story of two black holes that coalesced 3 billion light-years from Earth. So far, this is the farthest source from which gravitational waves have been detected...

Black holes could be "back doors" to other regions of the universe, a new study suggests. However, it is unlikely anyone passing through one of the gateways would survive, say scientists. First they would be "spaghettified" - stretched out like a strand of pasta - by the black hole's immense gravity. Once on the other side of the "door" the traveller would be compacted back to normal size, but could not count on being restored back to life.

The story starts in the 1980s, when astronomers found that small (stellar-mass) black holes emit X-ray light that flickers in a curious pattern. At first, this flickering occurs every few seconds; however, the time between each flicker shortens over the course of a few months, eventually stopping completely. This "quasi-periodic oscillation" (QPO) was thought to be a result of a phenomenon predicted by Albert Einstein's theory of general relativity — that any object with enough mass, like a black hole, will twist space-time as it spins. Later, scientists calculated that these gravitational vortices will cause the orbits of particles around...

Explanation: A new sky is becoming visible. When you look up, you see the sky as it appears in light -- electromagnetic radiation. But just over the past year, humanity has begun to see our once-familiar sky as it appears in a different type of radiation -- gravitational radiation. Today, the LIGO collaboration is reporting the detection of GW151226, the second confirmed flash of gravitational radiation after GW150914, the historic first detection registered three months earlier. As its name implies, GW151226 was recorded in late December of 2015. It was detected simultaneously by both LIGO facilities in Washington and Louisiana,...

An international team of scientists, including the University of Kentucky's Renbin Yan, have uncovered a new class of galaxies, called "red geysers," with supermassive black hole winds so hot and energetic that stars can't form. Over the last few billion years, a mysterious kind of "galactic warming" has caused many galaxies to change from a lively place where new stars formed every now and then to a quiet place devoid of fresh young stars. But the mechanism that produces this dramatic transformation and keeps galaxies quiet has been one of the biggest unsolved mysteries in galaxy evolution. "These galaxies have...

Hawking at Harvard At packed Sanders Theatre, theoretical physicist and cosmologist tackles the contradictory qualities of black holes April 18, 2016 | Editor's Pick Popular Stephanie Mitchell/Harvard Staff Photographer"If determinism — the predictability of the universe — breaks down in black holes, it could break down in other situations. Even worse, if determinism breaks down, we can’t be sure of our past history either. The history books and our memories could just be illusions. It is the past that tells us who we are. Without it, we lose our identity," said Stephen Hawking. By Peter Reuell, Harvard Staff Writer Twitter...

Artist's illustration of turbulent winds of gas swirling around a black hole. Some of the gas is spiraling inward, but some is being blown away. Credit: NASA, and M. Weiss (Chandra X -ray Center) ============================================================================================================================================== New research led by astrophysicists at York University has revealed the fastest winds ever seen at ultraviolet wavelengths near a supermassive black hole. "We're talking wind speeds of 20 per cent the speed of light, which is more than 200 million kilometres an hour. That's equivalent to a category 77 hurricane," says Jesse Rogerson, who led the research as part of his PhD thesis in...

Cosmic rays fired at Earth - now we know where from The violent region at the centre of our galaxy is the prime candidate, after gamma ray analysis, Bill Condie reports. Photo montage of gamma-rays as measured by the HESS array on the night sky over Namibia, with one of the small HESS telescopes in the foreground. Credit: H.E.S.S. Collaboration, Fabio Acero and Henning Gast Astronomers believe they may have identified the source of the stream of cosmic rays that rain down on Earth from outer space. Cosmic rays are extremely high-energy particles such as protons and atomic nuclei....

upermassive black holes are the most extreme objects in the known universe, with masses millions or even billions of times the mass of our sun. Now astronomers have been able to study one of these behemoths inside a strange, distant quasar and they’ve made an astonishing discovery — it’s spinning one-third the speed of light. Studying a supermassive black hole some 3.5 billion light-years away is no easy feat, but this isn’t a regular object: it’s a quasar that shows quasi-periodic brightening events every 12 years or so — a fact that has helped astronomers reveal its extreme nature. Quasars...

[S]cientists...for some time now, they have been working with a model that states that the Universe consists of 4.9% “normal” matter (i.e. that which we can see), 26.8% “dark matter” (that which we can’t), and 68.3% “dark energy”. From what they have observed, scientists have also concluded that the normal matter in the Universe is concentrated in web-like filaments, which make up about 20% of the Universe by volume. But a recent study performed by the Institute of Astro- and Particle Physics at the University of Innsbruck in Austria has found that a surprising amount of normal matter may live...

A new photograph of galaxy NGC 4889 may look peaceful from such a great distance, but it’s actually home to one of the biggest black holes that astronomers have ever identified. The Hubble Space Telescope allowed scientists to capture photos of the galaxy, located in the Coma Cluster about 300 million light-years away. The supermassive black hole hidden away in NGC 4889 breaks all kinds of records, even though it is currently classified as dormant. So how big is it, exactly? Well, according to our best estimates, the supermassive black hole is roughly 21 billion times the size of the...

Bursts of gamma rays from the center of our galaxy are not likely to be signals of dark matter but rather other astrophysical phenomena such as fast-rotating stars called millisecond pulsars, according to two new studies, one from a team based at Princeton University and the Massachusetts Institute of Technology and another based in the Netherlands. Previous studies suggested that gamma rays coming from the dense region of space in the inner Milky Way galaxy could be caused when invisible dark matter particles collide. But using new statistical analysis methods, the two research teams independently found that the gamma ray...

TORONTO — Dark matter inspires many strange theories, but until now few have involved giant lizards and the origins of humanity. If physicist Lisa Randall’s theory is correct, however, there is a clear link between dark matter, the great unknown majority of universal stuff and the extinction of the dinosaurs, which cleared the path for the rise of mammals, including that special species, homo sapiens. Roughly, her idea is that the rotation of a vast disc of dark matter through our solar system dislodged an asteroid from a weak and distant orbit, and sent it hurtling toward Earth, where it...

Even gluttons can't eat forever. When black holes at the hearts of galaxies swell to 50 billion times the mass of our sun, they may lose the discs of gas they use as cosmic feedlots. Most galaxies host a supermassive black hole at their centre. Around this is a region of space where gas settles into an orbiting disc. The gas can lose energy and fall inwards, feeding the black hole. But these discs are known to be unstable and prone to crumbling into stars. Theoretically, a black hole could grow so big that it swallows up the stable part...

Mysterious high-energy particles known as cosmic rays zip through space at a wide range of energies, some millions of times greater than those produced in the world’s most powerful atom smasher. Scientists have long thought cosmic rays from inside our galaxy come from supernova explosions, but a new study has fingered a second source: the supermassive black hole at the heart of the Milky Way. With this new result, the search for cosmic ray origins, which has frustrated scientists for more than 100 years, has taken an unexpected new twist. “It’s very exciting,” says astrophysicist Andrew Taylor of the Dublin...

Explanation: Just press play to watch two black holes merge. Inspired by the first direct detection of gravitational waves by LIGO, this simulation video plays in slow motion but would take about one third of a second if run in real time. Set on a cosmic stage the black holes are posed in front of stars, gas, and dust. Their extreme gravity lenses the light from behind them into Einstein rings as they spiral closer and finally merge into one. The otherwise invisible gravitational waves generated as the massive objects rapidly coalesce cause the visible image to ripple and slosh...

Explanation: Gravitational radiation has been directly detected. The first-ever detection was made by both facilities of the Laser Interferometer Gravitational-Wave Observatory (LIGO) in Washington and Louisiana simultaneously last September. After numerous consistency checks, the resulting 5-sigma discovery was published today. The measured gravitational waves match those expected from two large black holes merging after a death spiral in a distant galaxy, with the resulting new black hole momentarily vibrating in a rapid ringdown. A phenomenon predicted by Einstein, the historic discovery confirms a cornerstone of humanity's understanding of gravity and basic physics. It is also the most direct detection of...

Black holes may sport a luxurious head of "hair" made up of ghostly, zero-energy particles, says a new hypothesis proposed by Stephen Hawking and other physicists. The new paper, which was published online Jan. 5 in the preprint journal arXiv, proposes that at least some of the information devoured by a black hole is stored in these electric hairs. Still, the new proposal doesn't prove that all the information that enters a black hole is preserved.

Stephen Hawking's New Black-Hole Paper, Translated: An Interview with Co-Author Andrew Strominger The Harvard string theorist explains the collaboration's long-awaited research on the black-hole information paradox Share on Facebook Share on Twitter Share on Reddit Email Print Share via Google+Stumble Upon Penrose diagram for a semiclassical evaporating black hole, as presented in "Soft Hair on Black Holes." CREDIT: Prahar Mitra In the mid 1970s, Stephen Hawking made a string of unnerving discoveries about black holes—that they could evaporate, even explode, and destroy all information about what had fallen in. Physicists spent the next 40 years sorting through the wreckage. Then last year, at a...