PUBLIC INFORMATION OFFICE 
JET PROPULSION LABORATORY 
CALIFORNIA INSTITUTE OF TECHNOLOGY 
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION 
PASADENA, CALIF. 91109. PHONE (818) 354-5011 




 
 
          The Deep Space Network, operated for NASA by the 
 
Jet Propulsion Laboratory, will provide tracking support for
 
the STS-26 flight of the space shuttle Discovery and for the
 
deployment and on-orbit checkout of Discovery's payload, the
 
Tracking and Data Relay Satellite-C (TDRS-C). 
 
          Shuttle support will be provided by the 26-meter 
 
antennas at Goldstone, Calif.; near Canberra, Australia; and

near Madrid, Spain. The Goldstone 26-meter antenna will 
 
provide prime support for the shuttle launch and landing 
 
phases of the mission. 
 
          The DSN 26-meter antennas will track Discovery 
 
during the launch sequence. Current flight plans call for 
 
Discovery's crew to open the shuttle's payload bay doors on 
 
the second orbit, and then transmit the information on 
 
TDRS-C's tape recorder to Earth. 
 
          The 26-meter DSN antenna at Goldstone will receive
 
the data, and then concentrate on the TDRS-C spacecraft's 
 
radio-frequency checks, beginning with orbit 3. If TDRS-C is
 
in good condition, it will be deployed from the shuttle's 
 
cargo bay on orbit 5. 
 
          Ignition of the IUS solid-rocket motor will take 
 
place on orbit 6. Other NASA antennas will then track the 
 


shuttle and the DSN will track TDRS-C and its inertial upper
 
stage as they reach geosynchronous orbit. 

          (Geosynchronous orbit is at 22,300 miles altitude,

where the spacecraft makes one orbit of Earth in 24 hours. 

TDRS-C will then appear to be stationary over the same spot 

on Earth. The exact location of TDRS-C will be determined 

after its on-orbit checkout is complete.) 

          The DSN will continue to track TDRS-C until four 

days into the shuttle flight, when it will return to 

tracking Discovery for the remainder of the flight and the 

landing at Edwards Air Force Base, Calif. 

          After Discovery has landed, the DSN antennas will 

once again track TDRS-C. 

          TDRS-C is an advanced communications satellite. 

The first TDRS was launched from the space shuttle in April 

1983. The second was lost in the explosion of the Challenger

in January 1986. 


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9/13/88 DB 
#1210