Pioneer
NASA Spacecraft Celebrates 20 Years of Service
The Tracking and
Data Relay Satellites comprise the space segment of NASA's communications relay
system.
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 Canter (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
Other TDRS-1 firsts include:
First satellite used to support Kennedy Space Canter
launches in the early 1990s, returning real time telemetry;
Closed the zone of communications exclusion over the
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);
Ffirst 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
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
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