accadacca
07-08-2010, 12:16 PM
http://news.discovery.com/space/2010/07/07/bubble-825x625.jpg
July 7, 2010 -- A relatively puny black hole in a neighbor galaxy is the motor behind a bubble of hot gas that already spans 1,000 light-years across and is growing at a rate of about 620,000 miles per hour.
The finding suggests that there may be more to black holes -- even relatively small ones four to 10 times the size of the sun -- than meets the eye.
WIDE ANGLE: Black Holes, Big and Small. (http://news.discovery.com/space/wide-angle-black-holes-big-small.html)
http://blogs.discovery.com/.a/6a00d8341bf67c53ef01348139109a970c-800wi (http://news.discovery.com/videos/space-3-questions-black-holes.html)
Kasey-Dee Gardner speaks with the astronomer who discovered the supermassive black hole at the center of our galaxy. (http://news.discovery.com/videos/space-3-questions-black-holes.html)
Black holes are objects so dense that not even light can escape their gravitational grips. But they do not pass through space unnoticed. Their heavy hands can be found tearing into neighbor objects, which are pulled apart and served up as disks of matter for the black hole's consumption.
SEE ALSO: Sloan Spots 100,000 Black Hole Behemoths (http://news.discovery.com/space/sloan-spots-one-hundred-thousand-black-hole-behemoths.html)
The feedings sometimes cause twin jet-like plumes of particles to form, though in small black holes the power of the jets pales in comparison to the total X-ray radiation stemming from the act of accretion itself.
Not so with the black hole in the outskirts of NGC 7793, a spiral galaxy about 12 million light-years away that is part of the Sculptor group. Astronomers discovered the object, also known as a microquasar, sports a massive pair of jets, far bigger than any found from similarly sized black holes.
SEE ALSO: Galactic Monster Mystery Solved (http://news.discovery.com/space/gas-cloud-spiral-galaxy.html)
The jets are slamming into surrounding interstellar gas, causing it to heat up and expand. Scientists used optical, X-ray and radio telescopes to study the gas bubble and tie it to the NGC 7793 black hole.
"They look very much like supernova remnants (the exploded remains of stars), but these bubbles are larger than normal and in a sense more energetic than normal supernova remnants," lead researcher Manfred Pakull, with the University of Strasbourg, France, told Discovery News.
"It's a very neat piece of research," added Dan Evans, an astrophysicist with the Massachusetts Institute of Technology. "When you see a black hole, the total energy output could be vastly larger than what you can observe with light. This has implications for how black holes grow, evolve and affect their environments."
The research is published in this week's issue of Nature.
July 7, 2010 -- A relatively puny black hole in a neighbor galaxy is the motor behind a bubble of hot gas that already spans 1,000 light-years across and is growing at a rate of about 620,000 miles per hour.
The finding suggests that there may be more to black holes -- even relatively small ones four to 10 times the size of the sun -- than meets the eye.
WIDE ANGLE: Black Holes, Big and Small. (http://news.discovery.com/space/wide-angle-black-holes-big-small.html)
http://blogs.discovery.com/.a/6a00d8341bf67c53ef01348139109a970c-800wi (http://news.discovery.com/videos/space-3-questions-black-holes.html)
Kasey-Dee Gardner speaks with the astronomer who discovered the supermassive black hole at the center of our galaxy. (http://news.discovery.com/videos/space-3-questions-black-holes.html)
Black holes are objects so dense that not even light can escape their gravitational grips. But they do not pass through space unnoticed. Their heavy hands can be found tearing into neighbor objects, which are pulled apart and served up as disks of matter for the black hole's consumption.
SEE ALSO: Sloan Spots 100,000 Black Hole Behemoths (http://news.discovery.com/space/sloan-spots-one-hundred-thousand-black-hole-behemoths.html)
The feedings sometimes cause twin jet-like plumes of particles to form, though in small black holes the power of the jets pales in comparison to the total X-ray radiation stemming from the act of accretion itself.
Not so with the black hole in the outskirts of NGC 7793, a spiral galaxy about 12 million light-years away that is part of the Sculptor group. Astronomers discovered the object, also known as a microquasar, sports a massive pair of jets, far bigger than any found from similarly sized black holes.
SEE ALSO: Galactic Monster Mystery Solved (http://news.discovery.com/space/gas-cloud-spiral-galaxy.html)
The jets are slamming into surrounding interstellar gas, causing it to heat up and expand. Scientists used optical, X-ray and radio telescopes to study the gas bubble and tie it to the NGC 7793 black hole.
"They look very much like supernova remnants (the exploded remains of stars), but these bubbles are larger than normal and in a sense more energetic than normal supernova remnants," lead researcher Manfred Pakull, with the University of Strasbourg, France, told Discovery News.
"It's a very neat piece of research," added Dan Evans, an astrophysicist with the Massachusetts Institute of Technology. "When you see a black hole, the total energy output could be vastly larger than what you can observe with light. This has implications for how black holes grow, evolve and affect their environments."
The research is published in this week's issue of Nature.