Hughes Space and Communications International, Inc., now Boeing Satellite Systems,
Inc., and XM Satellite Radio Inc. (XMTM) signed a contract 23 March 1998, for two BSS-702 model satellites, named XM 1 and XM 2 (nicknamed "Rock" and
"Roll"). These satellites are designed to provide state-of-the-art digital audio
radio programming directly to cars, homes and portable radios coast to coast. The
contract, amended in June 1998, calls for Boeing to deliver the high-power satellites in
geosynchronous orbit, using the Sea Launch vehicle. XM also has ordered long-lead parts
for a spare satellite.
Together, the two XM spacecraft will deliver up to 100 channels of crystal-clear,
digital-quality music, news and information to cars, homes and other listening
environments equipped with a small antenna. XM-capable radios and audio systems will be
marketed by Alpine Electronics, Inc., Delphi Delco, Pioneer Electronics Corporation and
the Sharp Corporation.
These satellites are among the most powerful ordered to date. Each is designed to
provide 18 kilowatts of total power at beginning of life. To generate such high power, the
two solar wings employ five panels each of high-efficiency, dual-junction gallium arsenide
solar cells. To provide 15 years' service, the BSS-702
carries the flight-proven xenon ion propulsion system (XIPS) for all on-orbit maneuvering.
Alcatel Espace of Toulouse, France, will provide the high-power, S-band, Digital Audio
Radio Service payload.
XM 1 and 2 suffer from a generic failure of the early BSS-702
model: the fogging of the concentrator mirrors on the solar arrays leads to reduced
available power.
XM 1 was retired in 2016 and was moved into a graveyard orbit above the geostationary belt.
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