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Allard Beutel
Headquarters, Washington            April 3, 2003
(Phone: 202/358-0951)

Susan Hendrix
Goddard Space Flight Center, Greenbelt, Md.
(Phone: 301/286-7745)

Sally Koris 
Northrop Grumman
(Phone: 310/812-4721)

RELEASE: 03-130

PIONEER NASA SPACECRAFT CELEBRATES 20 YEARS OF SERVICE

     NASA's original Tracking and Data Relay Satellite 
(TDRS-1), launched from the Space Shuttle Challenger (STS-6) 
in April 1983, went from almost being "lost in space," to a 
remarkable example of the agency's 'can do, never quit' 
attitude. On April 4, TDRS-1 celebrates 20 years of 
outstanding service and 'firsts.'

After deployment, the spacecraft's upper stage failed. NASA 
engineers at the Goddard Space Flight Center (GSFC) came to 
TDRS-1's rescue using the spacecraft's tiny, one-pound 
thrusters. They used the thrusters, over several months, to 
nudge the satellite into a geosynchronous Earth orbit. 
Because TDRS-1 has been inclining in its orbit almost one 
degree per year since its deployment, this satellite has 
been used in ways never expected. 

TDRS-1 began life by opening a new era in NASA satellite 
communications. It tracked low Earth-orbiting satellites, 
enabling NASA to issues commands and receive telemetry 
through most of their orbit. Working solo, TDRS-1 provided 
more communication coverage, in support of the September 
1983 Shuttle mission, than the entire network of NASA 
tracking stations had provided in all previous Shuttle 
missions.

The second TDRS satellite was destroyed in the Challenger 
accident in January 1986, so TDRS-1 was left alone in orbit 
for several years to carry the load. In March 1992, NASA 
called on TDRS-1 to quickly aid the agency's Compton Gamma 
Ray Observatory (CGRO), when data recorders onboard the 
spacecraft failed. 

Engineers constructed a ground station in Canberra, 
Australia to close the zone of communications exclusion and 
minimize science data loss. Controllers re-positioned TDRS-1 
in view of the new station. TDRS-1 was able to supplement 
the communications services provided by the other on-orbit 
TDRS satellites, providing the CGRO with downlink capability 
over previously inaccessible portions of its orbit. Since 
1992, NASA has used TDRS-1 for communications to very high 
latitude ground sites. 

Other TDRS-1 firsts include:

*  First satellite used to support Kennedy Space Center 
launches in the early 1990s, returning real time telemetry; 
*  Closed the zone of communications exclusion over the 
Indian Ocean, providing 100 percent coverage of the Space 
Shuttle and low inclination orbiting satellites via the TDRS 
constellation;
*  First connection to the Internet, and the first live Web 
cast from the North Pole, using TDRS-1 (recorded in Ripley's 
Believe It Or Not);
*  First Pole-to-Pole phone call using TDRS-1 to connect to 
the South Pole and Iridium for the North Pole (recorded in 
Ripley's Believe It Or Not and Guinness World Records in 
April 1999);

Due to increasing orbit inclination, TDRS-1 was the first 
satellite able to see both Poles. In cooperation with the 
National Science Foundation (NSF), an uplink/downlink 
station for TDRS-1 was installed in January 1998 at the 
exact South Pole. This terminal has given scientists at the 
Amundsen-Scott Base year around ability to return high 
volumes of science data to the continental U.S. daily for 
about five hours. 

NASA considered retiring the aging satellite in 1998, but 
instead allowed the NSF and others to use it for scientific, 
humanitarian and educational purposes. TDRS-1 was used in 
1998 for a medical emergency at McMurdo Station. Its high-
speed connectivity allowed scientists to conduct a 
telemedicine conference, allowing doctors in the U.S. to 
guide a welder through a real operation on a woman diagnosed 
with breast cancer. 

In 2000, TDRS-1 successfully supported an extended NSF/Coast 
Guard science expedition to the Gakal Ridge just below the 
North Pole. "We in the Space Network are extremely happy 
with the performance of TDRS-1 and look forward to many more 
'firsts,'" said Dick Schonbachler, Mission Commitment 
Manager at GSFC. Since TDRS-1 entered service in 1983, NASA 
has placed nine TDRS into specific geosynchronous orbits. 
The first six were built by TRW. Boeing Satellite Systems 
built three enhanced satellites. The Space Network uses the 
TDRS System to relay data and communications from more than 
one dozen customers, including the Shuttle, International 
Space Station and the Hubble Space Telescope. For more 
information about TDRS-1 and the TDRS System, on the 
Internet, visit:
http://nmsp.gsfc.nasa.gov/tdrss/tdrsshome.html

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