PUBLIC INFORMATION OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011
Contact: Franklin O'Donnell
FOR IMMEDIATE RELEASEDecember 4, 1996
SATELLITE OPERATIONS TRANSFERRED ACROSS THE ATLANTIC
Day-to-day routine orbital maintenance of two technology
demonstration satellites has been transferred rapidly and
inexpensively across the Atlantic from the United Kingdom to an
American university, thanks to standards developed by an
international program to which NASA was a major contributor.
The satellites, Space Technology Research Vehicle (STRV) 1a
and 1b, were developed, built and are owned by the Defence
Evaluation and Research Agency of the British Ministry of
Defence. Responsibility for their routine maintenance has been
delegated to the Laboratory for Atmospheric and Space Physics at
the University of Colorado, Boulder, CO.
The transfer was accomplished within four months at a cost
of less than $200,000, said Adrian J. Hooke, acting manager of
NASA's Space Operations Standards Program at the Jet Propulsion
Laboratory (JPL), Pasadena, CA, which facilitated the effort.
"This transfer was accomplished quickly and inexpensively
thanks to protocols that standardize the way spacecraft and
ground systems talk to each other," said Hooke. "These new
capabilities drastically lower the cost of integrating, testing
and operating spacecraft."
Launched in 1994, the two STRV satellites carry an
international suite of experiments studying the space environment
near Earth. The satellites are in highly elliptical orbits that
take them from 300 to 36,000 kilometers (185 to 22,300 miles)
above Earth, passing through zones of high radiation. Data
acquisition from the STRV spacecraft has been enhanced for much
of their mission with tracking support from NASA's Deep Space
Before the hand-off, the STRVs were used early in 1996 to
flight-test a suite of new operations protocols currently in
development that standardize file transfer, transport, security
and network issues in the communications link between the
satellites and ground. "In essence, the new way of communicating
with spacecraft will look a lot like the Internet," said Hooke.
"You will be able to transfer files to and from the spacecraft
just as you do on the Internet using what is known as file
transfer protocol (FTP) and the transmission control protocol
After operating the satellites for two years, the British
Defence Research Agency this year needed to close its ground
station at Lasham, England, for refurbishment in preparation for
the planned 1999 launch of the next two STRVs. JPL suggested the
operational transfer of the STRV satellites to the University of
Colorado as a demonstration of the new international
interoperability standards and as a way to both continue their
scientific missions and also to use them as "flying testbeds" for
new standards technologies.
Key among the protocols that eased the transition are new
telemetry and telecommand interfaces between both spacecraft and
ground systems that conform to standards developed by the
international Consultative Committee for Space Data Systems.
"Packetized telemetry and telecommand standards are the
underpinnings of all space missions from here on out," said
Hooke. "You will see then on low Earth orbiters, planetary
spacecraft like Cassini, the international Space Station -- they
are becoming the universal way of communicating with spacecraft."
Hooke said that the effort marked the first time
responsibility for routine orbital maintenance of satellites had
been delegated across national borders to a university. The
British Defense Research Agency retains full ownership and
executive control of the STRV satellites and will determine their
final disposition at the end of their lifetimes.
The cooperative effort -- which included the involvement of
NASA Headquarters, the U.S. Air Force Space and Missile Systems
Center and the U.S. Ballistic Missile Defense Organization --
also marks the beginning of a new era in which NASA and the U.S.
Department of Defense hope to realize large cost savings by using
strategic joint standardization in order to greatly increase the
level of commonality and interoperability across the US civil and
military space programs.
JPL manages the Space Operations Standards Program for
NASA's Office of Space Flight, Washington, DC.