Andrew Yee
December 21st 05, 05:30 PM
Office of Media Relations
University of California-Los Angeles
Media Contacts:
Stuart Wolpert
(310) 206-0511 / (310) 825-2585
FOR IMMEDIATE RELEASE: Tuesday, December 20, 2005
Astronomers Use Laser to Take Clearest Images of the Center of the Milky
Way
UCLA astronomers and colleagues have taken the first clear picture of the
center of our Milky Way galaxy, including the area surrounding the
supermassive black hole, using a new laser virtual star at the W.M. Keck
observatory in Hawaii.
"Everything is much clearer now," said Andrea Ghez, UCLA professor of
physics and astronomy, who headed the research team. "We used a laser to
improve the telescope's vision -- a spectacular breakthrough that will
help us understand the black hole's environment and physics. It's like
getting Lasik surgery for the eyes, and will revolutionize what we can do
in astronomy."
Astronomers are used to working with images that are blurred by the
Earth's atmosphere. However, a laser virtual star, launched from the Keck
telescope, can be used to correct the atmosphere's distortions and clear
up the picture. This new technology, called Laser Guide Star adaptive
optics, will lead to important advances for the study of planets in our
solar system and outside of our solar system, as well as galaxies, black
holes, and how the universe formed and evolved, Ghez said.
"We have worked for years on techniques for 'beating the distortions in
the atmosphere' and producing high-resolution images," she said. "We are
pleased to report the first Laser Guide Star adaptive optics observations
of the center of our galaxy."
Ghez and her colleagues took "snapshots" of the center of the galaxy,
targeting the supermassive black hole 26,000 light years away, at
different wavelengths. This approach allowed them to study the infrared
light emanating from very hot material just outside the black hole's
"event horizon," about to be pulled through.
"We are learning the conditions of the infalling material and whether this
plays a role in the growth of the supermassive black hole," Ghez said.
"The infrared light varies dramatically from week to week, day to day and
even within a single hour."
The research, federally funded by the National Science Foundation, will be
published Dec. 20 in the Astrophysical Journal Letters.
The research was conducted using the 10-meter Keck II Telescope, which is
the world's first 10-meter telescope with a laser on it. Laser Guide Star
allows astronomers to "generate an artificial bright star" exactly where
they want it, which reveals the atmosphere's distortions.
Since 1995, Ghez has been using the W.M. Keck Observatory to study the
galactic center and the movement of 200 nearby stars.
Black holes are collapsed stars so dense that nothing can escape their
gravitational pull, not even light. Black holes cannot be seen directly,
but their influence on nearby stars is visible, and provides a signature,
Ghez said. The supermassive black hole, with a mass more than 3 million
times that of our sun, is in the constellation of Sagittarius. The
galactic center is located due south in the summer sky.
The black hole came into existence billions of years ago, perhaps as very
massive stars collapsed at the end of their life cycles and coalesced into
a single, supermassive object, Ghez said.
Co-authors on the research include UCLA graduate students Seth Hornstein
and Jessica Lu; the adaptive optics team at W. M. Keck Observatory: David
Le Mignant, Marcos Van Dam and Peter Wizinowich; Antonin Bouchez (formerly
with the W. M. Keck Observatory) and Keith Matthews at Caltech; Mark
Morris, a UCLA professor of physics and astronomy; and Eric Becklin, a
UCLA professor of physics and astronomy.
Ghez provides more information, and images of the galactic center, at
http://www.astro.ucla.edu/research/galcenter/
University of California-Los Angeles
Media Contacts:
Stuart Wolpert
(310) 206-0511 / (310) 825-2585
FOR IMMEDIATE RELEASE: Tuesday, December 20, 2005
Astronomers Use Laser to Take Clearest Images of the Center of the Milky
Way
UCLA astronomers and colleagues have taken the first clear picture of the
center of our Milky Way galaxy, including the area surrounding the
supermassive black hole, using a new laser virtual star at the W.M. Keck
observatory in Hawaii.
"Everything is much clearer now," said Andrea Ghez, UCLA professor of
physics and astronomy, who headed the research team. "We used a laser to
improve the telescope's vision -- a spectacular breakthrough that will
help us understand the black hole's environment and physics. It's like
getting Lasik surgery for the eyes, and will revolutionize what we can do
in astronomy."
Astronomers are used to working with images that are blurred by the
Earth's atmosphere. However, a laser virtual star, launched from the Keck
telescope, can be used to correct the atmosphere's distortions and clear
up the picture. This new technology, called Laser Guide Star adaptive
optics, will lead to important advances for the study of planets in our
solar system and outside of our solar system, as well as galaxies, black
holes, and how the universe formed and evolved, Ghez said.
"We have worked for years on techniques for 'beating the distortions in
the atmosphere' and producing high-resolution images," she said. "We are
pleased to report the first Laser Guide Star adaptive optics observations
of the center of our galaxy."
Ghez and her colleagues took "snapshots" of the center of the galaxy,
targeting the supermassive black hole 26,000 light years away, at
different wavelengths. This approach allowed them to study the infrared
light emanating from very hot material just outside the black hole's
"event horizon," about to be pulled through.
"We are learning the conditions of the infalling material and whether this
plays a role in the growth of the supermassive black hole," Ghez said.
"The infrared light varies dramatically from week to week, day to day and
even within a single hour."
The research, federally funded by the National Science Foundation, will be
published Dec. 20 in the Astrophysical Journal Letters.
The research was conducted using the 10-meter Keck II Telescope, which is
the world's first 10-meter telescope with a laser on it. Laser Guide Star
allows astronomers to "generate an artificial bright star" exactly where
they want it, which reveals the atmosphere's distortions.
Since 1995, Ghez has been using the W.M. Keck Observatory to study the
galactic center and the movement of 200 nearby stars.
Black holes are collapsed stars so dense that nothing can escape their
gravitational pull, not even light. Black holes cannot be seen directly,
but their influence on nearby stars is visible, and provides a signature,
Ghez said. The supermassive black hole, with a mass more than 3 million
times that of our sun, is in the constellation of Sagittarius. The
galactic center is located due south in the summer sky.
The black hole came into existence billions of years ago, perhaps as very
massive stars collapsed at the end of their life cycles and coalesced into
a single, supermassive object, Ghez said.
Co-authors on the research include UCLA graduate students Seth Hornstein
and Jessica Lu; the adaptive optics team at W. M. Keck Observatory: David
Le Mignant, Marcos Van Dam and Peter Wizinowich; Antonin Bouchez (formerly
with the W. M. Keck Observatory) and Keith Matthews at Caltech; Mark
Morris, a UCLA professor of physics and astronomy; and Eric Becklin, a
UCLA professor of physics and astronomy.
Ghez provides more information, and images of the galactic center, at
http://www.astro.ucla.edu/research/galcenter/