Supermassive black holes, notorious for ripping apart and swallowing
stars, might also help seed interstellar space with the elements
necessary for life, such as hydrogen, carbon, oxygen and iron,
scientists say.

Using NASA’s Chandra X-ray Observatory and ESA’s XMM-Newton
satellite, scientists at Penn State University and the Massachusetts
Institute of Technology found evidence of high-speed winds blowing
away copious amounts of gas from the cores of two quasar galaxies,
which are thought to be powered by black holes.

“The winds we measured imply that as much as a billion suns’ worth of
material is blown away over the course of a quasar’s lifetime,” said
George Chartas of the Penn State Astronomy and Astrophysics
Department, who led the observations. The winds might also regulate
black hole growth and spur the creation of new stars, according to
the science team, which includes Niel Brandt and Gordon Garmire of
Penn State and Sarah Gallagher of MIT.

These results are presented today in a press conference at the
meeting of the High Energy Astrophysics Division of the American
Astronomical Society at Mt. Tremblant, Quebec. Different from
high-speed jets shooting off subatomic particles, the newly
identified gusts arise from the disk of matter orbiting the black
hole, called the accretion disk, once thought to be a one-way ticket
into the black hole.

Black holes are objects so dense that nothing, not even light, can
escape their gravitational attraction. But this only applies once
matter crosses the theoretical border of a black hole, called the
event horizon. Outside the event horizon, the tug of gravity is
strong, but matter and light can escape.

Theorists have suggested that a wind could blow away material from
its accretion disk and pepper the interstellar region with heavier
elements. The wind is created by radiation pressure, analogous to
earthly winds created by varying high and low air pressure systems.

Chartas and his colleagues observed two quasars, which are
exceedingly distant star-like objects thought to be the bright cores
of galaxies fueled by a supermassive black hole. With Chandra, the
team observed a quasar called APM 08279+5255; and with the European
Space Agency’s XMM-Newton, they observed a quasar named PG1115+080.

Both quasars are billions of light years away from Earth. However,
APM 08279+5255 was naturally magnified by a factor of about 100 and
PG1115+080 by a factor of about 25 through a process called
gravitational lensing. Essentially, their light, while en route to
us, was distorted and magnified by the gravity of intervening
galaxies acting like telescope lenses.

With the natural boost in magnification, coupled with the X-ray
observatories’ abilities, the scientists could ascertain several key
properties in the quasar light, such as the speed of the gas that
absorbed the light, as well as the material’s proximity to the black
hole.

The team found the first observational evidence of a wind component
transporting a substantial amount of carbon, oxygen and iron into the
interstellar and intergalactic medium. The wind was moving at 40
percent light speed, considerably faster than predicted.

Brandt said the observation may spur new theoretical work about black
hole winds and their effect on their environs. For example, Brandt
said, “the wind might provide insight to the relationship between
black hole mass and the central bulge of its host galaxy.”

Chandra, launched in July 1999, is the third in NASA’s Great
Observatory series, a sister craft to the Hubble Space Telescope.
ESA’s XMM-Newton was launched from French Guiana in December 1999 and
carries three advanced X-ray telescopes.

NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the
Chandra program, and TRW, Inc., Redondo Beach, Calif., is the prime
contractor for the spacecraft. The Smithsonian’s Chandra X-ray Center
controls science and flight operations from Cambridge, Mass., for the
Office of Space Science at NASA Headquarters, Washington.

IMAGES:

For more information and images of these quasars, refer to:
http://www.science.psu.edu/alert/Chartas3-2003.htm

PRESS ROOM CONTACT: (+1) 819-681-4200

during the AAS High Energy Astrophysics meeting in Quebec, 8:30 a.m.
to about 6:00 p.m., 24 March through noon 26 March (but not during press conference on 25
March from 10:00 to about 11:00 a.m.)

UNIVERSITY CONTACTS:

  • George Chartas at Penn State: (+1) 814-863-7946, gchartas@astro.psu.edu
  • Niel Brandt at Penn State: (+1) 814-865-3509, nbrandt@astro.psu.edu
  • Gordon Garmire at Penn State: (+1) 814-865-1117 or 863-9550, ggarmire@astro.psu.edu
  • Sarah Gallagher at MIT: (+1) 617-258-7348, scg@space.mit.edu
  • Barbara K. Kennedy (PIO) at Penn State: (+1) 814-863-4682, science@psu.edu