Stories tagged supermassive black holes

Black hole in action: Artist's rendition of a distant super-massive black hole warping space while busy eating up stellar material.
Courtesy NASA/JPL-CaltechScientists now have a better idea why stars can still form out of giant molecular clouds being ripped apart by the gravitational pull of a nearby massive black hole.

The observed existence of huge stars in eccentric orbits around the super-massive black hole believed to be located at the center of our Milky Way galaxy has puzzled scientists. How can stars form in such extreme environments? Gravitational forces would be tremendous near the black hole, tearing apart everything in the immediate region.

The computer simulations, done by researchers from St Andrews University in the UK, show how a molecular cloud – a normal stellar nursery – is torn apart by the black hole’s immense gravitation pull. Although the powerful gravity-well eats a huge portion of the gas cloud, the remaining gases are still able to accrete more material and coalesce into stars.

This is possible because as a molecular cloud enters the black hole’s gravitational field it begins to form into a spiraling elliptical disk. The disk’s matter nearest the black hole is sucked into the gravitational vortex, while energy is transferred to the remaining outer material. This transferred energy allows the remnants to retain the eccentric orbital path as they form into huge stars many times the mass of the Sun.

"These simulations show that young stars can form in the neighborhood of super-massive black holes as long as there is a reasonable supply of massive clouds of gas from further out in the galaxy," said co-author Ian Bonnell. The study’s results appear in the current issue of Science.

The stars live fairly short lives - perhaps only about 10 million years. But their existence could help explain some of the mysteries surrounding black holes in galaxies.

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Galactic glue: Are supermassive black holes holding our galaxies together? That's the conclusion many astronomers are coming to as they study these huge, massive sites at the core of many galaxies. (Photo courtesy of NASA)The black hole: our metaphor du joir to describe something that completely sucks up another thing.

But new research is re-examining black holes and the impact they play in space. Not only are they sucking up old space materials, but they may be spitting out new galactic bodies and holding complete galaxies together.

UCLA astronomer Andrea Ghez is at the hub of this new research. Using some of the most technically advanced telescopic equipment available, for four years she’s been watching and reporting on new black hole phenomena. And she may have uncovered a new, more powerful type of black hole, the “supermassive” black hole.

She and others who are studying the same things now postulate that most of the universe’s galaxies have “supermassive” black holes at their center. These mega-black holes have gravitational fields that are hundreds of thousands of times stronger than the conventional black hole.

While research for a long time has chronicled how regular black holes can eat up stars, planets and even light, the new supermassive black holes might also be celestial body creators. Just like what often happens to us after eating a big meal, these super-sized black holes belch out jets of energized particles and radiation over a distance of millions of light years, creating new galaxies and celestial bodies.

If your sitting there starting to feel a mysterious uncomfortable tug on you, don’t worry. Here in the Milky Way it’s believed we have a very small, dormant supermassive black hole holding our galaxy together. It’s about 27,000 light years away from us and is relatively small, having the mass of about 4 millions suns. And there’s no evidence that it is spewing out any jets of radiation and energy particles.

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