Bowser
09-13-00, 06:43 PM
William Steigerwald September 13, 2000
Goddard Space Flight Center, Greenbelt, Md.
(Phone: *** *** ****)
Release No. 00-112
New X-ray Telescope Technology Propels Virtual Journey to Black Hole
Scientists have designed and successfully tested a new type of
X-ray telescope that, when fully developed and placed in orbit, may
capture the first images of a black hole and resolve details of
nearby stars as clearly as we see our own Sun today. The report is
published in the September 14 issue of Nature.
The X-ray telescope designed by University of Colorado and NASA
has the potential of providing resolution a thousand times sharper
than the finest images available today in any wavelength and a
million times better than what current X-ray telescopes can muster.
In orbit, such an instrument could resolve a region the size of a
dinner plate on the surface of the Sun. The telescope employs a
technique called interferometry, a process of coupling two or more
telescopes together to synthetically build an aperture equal to the
separation of the telescopes.
"Through the power of ultra-high resolution, we could journey to
distant places without need for a warp drive," said Dr. Webster Cash,
a professor at University of Colorado and lead author on the Nature
article. "This new approach allows X-ray astronomers to essentially
jump from telescopes with resolution no finer than what an amateur
uses in the backyard to an observatory far more precise than Hubble."
X-ray telescopes are essential for studying black holes up
close, said Dr. Cash, because the X-ray band is the dominant
radiation in the region directly surrounding these strange objects. X
rays can also travel through the dusty Milky Way galaxy in ways that
optical light cannot. X-ray telescopes must be placed in orbit, for
celestial X rays do not penetrate the Earth's atmosphere.
Dr. Cash and his colleagues have achieved 100 milliarcsecond
resolution (similar to Hubble) in the laboratory with their X-ray
interferometer. This is a five-fold improvement over the best
conventional X-ray telescopes, which achieve 500 milliarcsecond
resolution.
This interferometry design is currently under study at Goddard
Space Flight Center in Greenbelt, Md., for two proposed NASA missions
with the ultimate goal of imaging a black hole. MAXIM, the
Microarcsecond X-ray Imaging Mission, could achieve 100-nanoarcsecond
resolution and would entail a fleet of spacecraft with separate
optics flying in precise formation. The MAXIM Pathfinder would be a
smaller mission with all the X-ray optics on one spacecraft,
achieving 100-microarcsecond resolution. These interferometerswould
complement, not replace, large area X-ray telescopes also planned for
the future.
With 100 microarcsecond resolution, astronomers could image the
coronae of nearby stars, seeing the actual disks of other stars which
appear now only as points of light. With 100 nanoarcsecond
resolution, astronomers could attain one of astronomy's ultimate
goals -- imaging a black hole. (It is a thousand-fold increase in
each jump from "milli" to "micro" to "nano".)
"Black holes hold an almost mythical attraction," said Dr.
Nicholas White, head of Goddard's Laboratory for High Energy
Astrophysics. "Compelling evidence that black holes exist has come
from observations of their gravitational effect on nearby objects,
but the ultimate proof is yet to come -- a direct image of the 'black
dot'. The X-ray interferometer may take us there."
Interferometry is a common practice in radio astronomy (e.g. the
Very Large Baseline Array) and an emerging technique for optical
astronomers (e.g. the Keck Observatory). The technique is similar to
the way sound waves can be combined to either cancel each other out
(resulting in silence) or amplify the sound. NASA's first orbiting
optical interferometer, called the Space Interferometry Mission, is
scheduled for launch in 2006.
The Chandra X-ray Observatory, NASA's most powerful X-ray
telescope to date, has generated a multitude of major astronomical
discoveries in the 15 months since its launch. Chandra achieves its
unprecedented 500 milliarcsecond resolution not through
interferometry but rather through highly polished and carefully
aligned mirrors.
Joining Dr. Cash on the Nature article are Drs. Ann Shipley and
Steve Osterman, both at University of Colorado, and Dr. Marshall Joy
of NASA's Marshall Space Flight Center in Huntsville, Ala. Testing of
the prototype X-ray interferometer took place at NASA-Marshall in
1999.
The proposed MAXIM and Pathfinder missions would launch after 2010.
For information about MAXIM, refer to: http://maxim.gsfc.nasa.gov.
For more information about X-ray interferometry, refer to: http://casa.colorado.edu/~wcash/interf/Interfere.htm.
------------------
It's all very large.
Goddard Space Flight Center, Greenbelt, Md.
(Phone: *** *** ****)
Release No. 00-112
New X-ray Telescope Technology Propels Virtual Journey to Black Hole
Scientists have designed and successfully tested a new type of
X-ray telescope that, when fully developed and placed in orbit, may
capture the first images of a black hole and resolve details of
nearby stars as clearly as we see our own Sun today. The report is
published in the September 14 issue of Nature.
The X-ray telescope designed by University of Colorado and NASA
has the potential of providing resolution a thousand times sharper
than the finest images available today in any wavelength and a
million times better than what current X-ray telescopes can muster.
In orbit, such an instrument could resolve a region the size of a
dinner plate on the surface of the Sun. The telescope employs a
technique called interferometry, a process of coupling two or more
telescopes together to synthetically build an aperture equal to the
separation of the telescopes.
"Through the power of ultra-high resolution, we could journey to
distant places without need for a warp drive," said Dr. Webster Cash,
a professor at University of Colorado and lead author on the Nature
article. "This new approach allows X-ray astronomers to essentially
jump from telescopes with resolution no finer than what an amateur
uses in the backyard to an observatory far more precise than Hubble."
X-ray telescopes are essential for studying black holes up
close, said Dr. Cash, because the X-ray band is the dominant
radiation in the region directly surrounding these strange objects. X
rays can also travel through the dusty Milky Way galaxy in ways that
optical light cannot. X-ray telescopes must be placed in orbit, for
celestial X rays do not penetrate the Earth's atmosphere.
Dr. Cash and his colleagues have achieved 100 milliarcsecond
resolution (similar to Hubble) in the laboratory with their X-ray
interferometer. This is a five-fold improvement over the best
conventional X-ray telescopes, which achieve 500 milliarcsecond
resolution.
This interferometry design is currently under study at Goddard
Space Flight Center in Greenbelt, Md., for two proposed NASA missions
with the ultimate goal of imaging a black hole. MAXIM, the
Microarcsecond X-ray Imaging Mission, could achieve 100-nanoarcsecond
resolution and would entail a fleet of spacecraft with separate
optics flying in precise formation. The MAXIM Pathfinder would be a
smaller mission with all the X-ray optics on one spacecraft,
achieving 100-microarcsecond resolution. These interferometerswould
complement, not replace, large area X-ray telescopes also planned for
the future.
With 100 microarcsecond resolution, astronomers could image the
coronae of nearby stars, seeing the actual disks of other stars which
appear now only as points of light. With 100 nanoarcsecond
resolution, astronomers could attain one of astronomy's ultimate
goals -- imaging a black hole. (It is a thousand-fold increase in
each jump from "milli" to "micro" to "nano".)
"Black holes hold an almost mythical attraction," said Dr.
Nicholas White, head of Goddard's Laboratory for High Energy
Astrophysics. "Compelling evidence that black holes exist has come
from observations of their gravitational effect on nearby objects,
but the ultimate proof is yet to come -- a direct image of the 'black
dot'. The X-ray interferometer may take us there."
Interferometry is a common practice in radio astronomy (e.g. the
Very Large Baseline Array) and an emerging technique for optical
astronomers (e.g. the Keck Observatory). The technique is similar to
the way sound waves can be combined to either cancel each other out
(resulting in silence) or amplify the sound. NASA's first orbiting
optical interferometer, called the Space Interferometry Mission, is
scheduled for launch in 2006.
The Chandra X-ray Observatory, NASA's most powerful X-ray
telescope to date, has generated a multitude of major astronomical
discoveries in the 15 months since its launch. Chandra achieves its
unprecedented 500 milliarcsecond resolution not through
interferometry but rather through highly polished and carefully
aligned mirrors.
Joining Dr. Cash on the Nature article are Drs. Ann Shipley and
Steve Osterman, both at University of Colorado, and Dr. Marshall Joy
of NASA's Marshall Space Flight Center in Huntsville, Ala. Testing of
the prototype X-ray interferometer took place at NASA-Marshall in
1999.
The proposed MAXIM and Pathfinder missions would launch after 2010.
For information about MAXIM, refer to: http://maxim.gsfc.nasa.gov.
For more information about X-ray interferometry, refer to: http://casa.colorado.edu/~wcash/interf/Interfere.htm.
------------------
It's all very large.