STS-93 Readies for Lift-Off with Chandra
Observatory
The next Shuttle flight will occur sometime in the Spring of 1999,
and carry in its payload bay NASA's next X-ray astronomy satellite.
The exact date for launch is not yet determined due to a recent
delay, but it will occur no earlier than April 8. This flight will
also be the first time a woman astronaut, US Air Force Colonel
Eileen Collins (http://starchild.gsfc.nasa.gov/docs/StarChild/whos_who_level2/collins.html), will serve as the Flight Commander. STS-93 will
be
the 94th Space Shuttle flight, and the 26th flight for the orbiter
Columbia.
The primary objective of STS-93 is to deploy the Chandra X-ray
Observatory. The Chandra X-ray Observatory was created to conduct
comprehensive studies of the Universe at X-ray wavelengths with
images 25 times sharper than previously possible. Chandra's
improved sensitivity will make possible more detailed studies of
black holes, supernovae, and dark matter; it will increase our
understanding of the origin, evolution, and destiny of the Universe.
Chandra consists of three major elements: a spacecraft with an
inertial upper stage rocket motor, a telescope, and a science
instrument module.
NASA recently announced that it would delay January's planned
shipment of the Chandra X-ray Observatory from prime contractor
TRW Space and Electronics Group to NASA's Kennedy Space Center.
The postponement will allow TRW to evaluate and correct a potential
problem with several printed circuit boards in the observatory's
command and data management system. TRW notified NASA of a potential
problem last week after another spacecraft being built by the
company experienced a failure during testing that was attributed to
similar printed circuit boards. The problem has been traced to poor
conductivity between different layers of the boards. The boards
are used in Chandra's main command and telemetry unit, as well as
in four remote units. These units provide command and data
communications links between the observatory's computer and
subsystems. NASA has directed TRW to remove and replace the
boards in the main unit, and to conduct further tests and
evaluation to determine if it is also necessary to replace the
boards in the remote units. The repair, if limited to boards in
the main command and telemetry unit, is expected to delay shipment
to Kennedy by approximately one week. This will result in
approximately a five-week slip in the observatory's launch
readiness date, in order to allow for integration and testing of
the units at Kennedy. If boards in the remote units must also be
replaced, a more extensive slip is anticipated.
NASA's premier X-ray observatory was recently named the Chandra
X-ray Observatory in honor of the late Indian-American Nobel
laureate, Subrahmanyan Chandrasekhar. This occurred after a naming
contest which attracted 6,000 entries from fifty states and
sixty-one countries. The winning name and essays, and the runner-up
names and essays, were decided by an elite panel that included
prominent scientists, a space science executive, and nationally
recognized science reporters. Chandrasekhar (1910-1995), known to
the world as Chandra (which means "moon" or "luminous" in Sanskrit),
is widely regarded as one of the foremost astrophysicists of the
twentieth century.
Additional Links
Tell me more about the Chandra X-ray Observatory (http://xrtpub.harvard.edu/)
Tell me more about Dr. Chandrasekhar (http://xrtpub.harvard.edu/contest/chandra_bio.html)
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