(-08-) Date: Jan 30 19:45 UTC
Subject: X-ray Telescope Mirrors Complete
From: NasaNews
NASA'S X-RAY TELESCOPE MIRRORS COMPLETED AHEAD OF SCHEDULE
A space-based observatory, under construction for NASA, has met an
important milestone--polishing and measurement of the observatory's
eight mirrors, one of the project's toughest technical challenges, has
been completed four months ahead of schedule at Hughes Danbury Optical
Systems (HDOS), Danbury, CT.
Data from the observatory, called the Advanced X-ray Astrophysics
Facility (AXAF), will be used to study X-ray radiation and is expected
to significantly improve scientific understanding of some of the most
energetic and violent processes in the universe. Launch of the AXAF is
scheduled for September 1998.
The observatory will produce picture-like images and spectrograms which
will yield information on temperature and chemical composition of the
objects it observes. Among the objects that will be observed are
neutron stars, black hole candidates, debris from supernova explosions,
quasars, the centers of active galaxies and hot gas in individual
galaxies and clusters of galaxies.
AXAF will produce spectrographic information about the temperature and
chemical composition of objects by separating the radiation received
according to wavelength, much as a prism splits visible light into
constituent colors. The observatory will produce 'picture-like' X-ray
images analogous to images in visible light made by traditional
telescopes. Once in orbit and operational, AXAF will provide
scientists with the most detailed views of the universe ever obtained
through observation of X-ray emissions.
The next step for AXAF is the precise alignment of the mirrors. The
first and largest pair of mirrors currently are being aligned in a
pathfinder mirror assembly at Eastman-Kodak Company (EKC), Rochester,
NY. After completion of this pathfinder alignment effort, the mirrors
will be shipped to Optical Coating Laboratory, Inc. (OCLI) in Santa
Rosa, CA, where they will be coated with iridium, returned to Kodak,
integrated and aligned into the High Resolution Mirror Assembly. The
remaining six mirrors for AXAF also will be coated at OCLI and sent to
EKC for assembly.
In 1996, all of the AXAF flight optics and detectors required to meet
the science mission objectives will be aligned and tested in the X-ray
Calibration Facility at Marshall.
AXAF is designed to be complementary to NASA's Great Observatories
already in orbit -- the Hubble Space Telescope launched in 1990, and
the Compton Gamma-Ray Observatory, launched in 1991. Each observatory
makes observations of stars, galaxies, and other astronomical objects
in distinct and separate wavelengths of energy, including visible
light, ultraviolet, gamma rays, and, in the case of AXAF, X-rays.
The AXAF development team consists of NASA, the Smithsonian
Astrophysical Observatory, TRW, HDOS, EKC and the Marshall Space Flight
Center, which manages the project for NASA's Office of Space Science,
Washington, DC.
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- T o d d E. V a n H o o s e a r -
``'''vanhoose@lalaland.cl.msu.edu - vanhoose@msu.edu - vanhoose@lalaland.cl.msu.edu
(._.) Michigan State University - East Lansing, MI USA
(_) Computer Laboratory - Department of Communication
`---' <A HREF="http://lalaland.cl.msu.edu/~vanhoose/">My Home Page</A>
"Give me ambiguity or give me something else."
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