Andrew Yee[_1_]
April 25th 07, 05:22 AM
Public Affairs Office
Harvard-Smithsonian Center for Astrophysics
Cambridge, Massachusetts
For more information, contact:
David A. Aguilar, Director of Public Affairs
Harvard-Smithsonian Center for Astrophysics
617-495-7462
Christine Pulliam, Public Affairs Specialist
Harvard-Smithsonian Center for Astrophysics
617-495-7463
For Release: Friday, April 20, 2007
Release No.: 2007-09
Black Holes May Fill the Universe with Seeds of Life
Cambridge, MA -- New research shows that black holes are not the ultimate
destroyers that are often portrayed in popular culture. Instead, warm gas
escaping from the clutches of enormous black holes could be one source of
the chemical elements that make life possible.
Immediately after the Big Bang, the universe contained only hydrogen and
helium. Heavier chemical elements had to be cooked up inside the first
stars, then scattered throughout space to be incorporated in next-generation
stars and their planets. Black holes may have helped to distribute those
elements across the cosmos.
Black holes are not all-consuming monsters. Until gas crosses the boundary
known as the event horizon, it can still escape if it is heated
sufficiently.
"One of the big questions in cosmology is how much influence massive black
holes exert on their surroundings," said co-author Martin Elvis of the
Harvard-Smithsonian Center for Astrophysics (CfA). "This research helps
answer that question."
An international team of astronomers has found that hot winds from giant
black holes in galactic centers may blow heavy elements like carbon and
oxygen into the vast tracts of space between galaxies.
The team, led by Yair Krongold of the Universidad Nacional Autonoma de
Mexico, studied the supermassive black hole at the center of the galaxy NGC
4051. They found that gas was escaping from much closer to the black hole
than previously thought. The outflow source is located about 2,000
Schwarzschild radii from the black hole, or about five times the size of
Neptune's orbit. (The Schwarzschild radius is the black hole's "point of no
return" -- about 4 million miles for the black hole in NGC 4051.)
The team could also determine the fraction of gas that was avoiding being
swallowed. That fraction ended up being smaller than earlier studies
suggested.
"We calculate that between 2 to 5 percent of the accreting material is
flowing back out," says team member Fabrizio Nicastro of the CfA.
Winds from black holes have been clocked at speeds of up to 4 million miles
per hour. Over thousands of years, the chemical elements such as carbon and
oxygen in those winds can travel immense distances, eventually becoming
incorporated into the cosmic clouds of gas and dust, called nebulae, that
will form new stars and planets.
This research, which used data from the European Space Agency's XMM-Newton
satellite, is being reported in the April 20 issue of The Astrophysical
Journal.
Note to editors: Images to accompany this release are online at
http://cfa-www.harvard.edu/press/2007/pr200709_images.html
Harvard-Smithsonian Center for Astrophysics
Cambridge, Massachusetts
For more information, contact:
David A. Aguilar, Director of Public Affairs
Harvard-Smithsonian Center for Astrophysics
617-495-7462
Christine Pulliam, Public Affairs Specialist
Harvard-Smithsonian Center for Astrophysics
617-495-7463
For Release: Friday, April 20, 2007
Release No.: 2007-09
Black Holes May Fill the Universe with Seeds of Life
Cambridge, MA -- New research shows that black holes are not the ultimate
destroyers that are often portrayed in popular culture. Instead, warm gas
escaping from the clutches of enormous black holes could be one source of
the chemical elements that make life possible.
Immediately after the Big Bang, the universe contained only hydrogen and
helium. Heavier chemical elements had to be cooked up inside the first
stars, then scattered throughout space to be incorporated in next-generation
stars and their planets. Black holes may have helped to distribute those
elements across the cosmos.
Black holes are not all-consuming monsters. Until gas crosses the boundary
known as the event horizon, it can still escape if it is heated
sufficiently.
"One of the big questions in cosmology is how much influence massive black
holes exert on their surroundings," said co-author Martin Elvis of the
Harvard-Smithsonian Center for Astrophysics (CfA). "This research helps
answer that question."
An international team of astronomers has found that hot winds from giant
black holes in galactic centers may blow heavy elements like carbon and
oxygen into the vast tracts of space between galaxies.
The team, led by Yair Krongold of the Universidad Nacional Autonoma de
Mexico, studied the supermassive black hole at the center of the galaxy NGC
4051. They found that gas was escaping from much closer to the black hole
than previously thought. The outflow source is located about 2,000
Schwarzschild radii from the black hole, or about five times the size of
Neptune's orbit. (The Schwarzschild radius is the black hole's "point of no
return" -- about 4 million miles for the black hole in NGC 4051.)
The team could also determine the fraction of gas that was avoiding being
swallowed. That fraction ended up being smaller than earlier studies
suggested.
"We calculate that between 2 to 5 percent of the accreting material is
flowing back out," says team member Fabrizio Nicastro of the CfA.
Winds from black holes have been clocked at speeds of up to 4 million miles
per hour. Over thousands of years, the chemical elements such as carbon and
oxygen in those winds can travel immense distances, eventually becoming
incorporated into the cosmic clouds of gas and dust, called nebulae, that
will form new stars and planets.
This research, which used data from the European Space Agency's XMM-Newton
satellite, is being reported in the April 20 issue of The Astrophysical
Journal.
Note to editors: Images to accompany this release are online at
http://cfa-www.harvard.edu/press/2007/pr200709_images.html