Astronomers may be a step closer to solving the mystery of a strange object seen orbiting the massive black hole at the center of our Milky Way galaxy.
Dubbed G2, the object was first spotted in 2011 and was thought initially to be a gas cloud on the verge of being ripped apart by the black hole, which is known as Sagittarius A*. But when the object stayed intact, some scientists suggested G2 was something else: a pair of binary stars.
But now a team of scientists at the Max Planck Institute for Extraterrestrial Physics in Garching, Germany have sparked new debate, offering more evidence to support the gas cloud theory.
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Simulation of gas cloud G2 after close approach to the black hole at the center of the Milky Way | ESO/MPE/Marc Schartmann
Black holes might end their lives by transforming into their exact opposite — ‘white holes’ that explosively pour all the material they ever swallowed into space, say two physicists. The suggestion, based on a speculative quantum theory of gravity, could solve a long-standing conundrum about whether black holes destroy information.
The theory suggests that the transition from black hole to white hole would take place right after the initial formation of the black hole, but because gravity dilates time, outside observers would see the black hole lasting billions or trillions of years or more, depending on its size. If the authors are correct, tiny black holes that formed during the very early history of the Universe would now be ready to pop off like firecrackers and might be detected as high-energy cosmic rays or other radiation. In fact, they say, their work could imply that some of the dramatic flares commonly considered to be supernova explosions could in fact be the dying throes of tiny black holes that formed shortly after the Big Bang.
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Artist’s conception of a black hole. | MARK GARLICK via Getty Images
Turns out, Neil deGrasse Tyson hates another science-based movie more than “Gravity.” TMZ caught up with the “Cosmos” host and asked him which space movie is the most scientifically inaccurate. After calling the gossip site “the dark energy permeating the vacuum of space wherever you look,” he awarded the title to the original Disney movie “The Black Hole.”
Tyson is known for his obsession with perfection when it comes to space in movies (James Cameron altered the skyscape in “Titanic” at the astrophysicist’s request), and he called the “The Black Hole” “embarrassing” before going on a rant about all the flubs and liberties Disney took in making the 1979 hit.
“They not only got none of the physics right about falling into a black hole, had they gotten it right it would have been a vastly more interesting movie.”
When a black hole swallows a star, things get violent. Very violent.
At least, that’s what scientists found in a new study when they used computer simulations to mimic the destruction of a star as it falls into a giant black hole. Just check it out in the video.
The simulations show that when the gravitational force of a supermassive black hole pulls in a star, the star is stretched into a long blob before it’s destroyed. About half of the star’s mass may get ejected as a stream of debris and the other half eventually may spiral into the black hole, forming what’s called an “accretion disk.”
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Illustration of a star distorted by supermassive black hole.
What’s at the center of a black hole? And what happens at the edge of a black hole?
Stephen Hawking has some big ideas that answer these big questions. Called one of the most influential physicists of our time, you might assume that his theories are too complicated for the layperson to wrap his or her mind around.
But in some ways, his ideas are easier to understand than you might think. Through animation and narration, The Guardian’s science correspondent Alok Jha explains them all in a two-and-half-minute cartoon in a way that everyone can easily grasp. Check it out above.
And why give Hawking’s theories the cartoon treatment?
“I suppose the incredible thing is that he came up with all these profound, provocative insights without the convenience of being able to write anything down,” Jha says in the video. Hawking, who authored A Brief History of Time, is paralyzed as a result of motor neuron disease.
Astronomers have seen a distant galaxy that blasts away material with two trillion times the energy the sun emits — the biggest such eruption ever seen. That ejection of matter could answer an important question about the universe: why are the black holes in the centers of galaxies so light?
Computer models of the early universe usually produce a virtual cosmos that looks like ours except for one thing. The ratio of the mass of black holes in galaxy centers to the rest of the matter in galaxies is larger in the simulations than in the real universe.
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A supermassive black hole discovered by University of Texas researchers ranks among the largest ever observed.
The enormous black hole is located in NGC 1277, a small, lenticular galaxy 250 million light years from Earth in the constellation Perseus, Space.com reports.
The black hole’s event horizon — the “point of no return” within which nothing can escape — has a diameter 11 times greater than Neptune’s orbit around the Sun, according to a written statement issued by the university’s McDonald Observatory in Austin.
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Galaxy NGC 1277, shown here in a Hubble Space Telescope image, may contain the
largest black hole ever discovered.
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