The International Space Station spent a quiet week in orbit with flight controllers in Houston and Moscow monitoring onboard systems, while verifying backup command links through NASA's communications network.
One of the routine systems checks aboard the station included verifying the Unity module's early communications system is available for backup commanding to the Zarya. This is done by sending commands to Zarya via the communications system housed inside Unity using NASA's Tracking and Data Relay Satellite System. Both control centers in Houston and Korolev outside Moscow sent commands to Zarya through Unity.
Other station systems checked included the onboard motion control system used to refine the spin rate of the ISS, currently about three tenths of a degree per second. This maintains even temperatures on the overall structure and minimizes propellant usage to maintain the complex's orientation. Also, the batteries used to harness the sun's energy for electrical systems are cycling as expected with the exception of battery 1, which remains disconnected from the system. No impacts are foreseen with the lack of availability of the battery, which is likely to be replaced by the shuttle crew upon the next visit to the ISS early next year.
The next piece of the ISS was scheduled to arrive at Florida's Kennedy Space Center late yesterday. The 45 foot long truss segment, designated S1, was flown aboard NASA's Super Guppy from the Marshall Space Flight Center in Huntsville, AL, where it has been completing testing prior to shipment for final processing. The S1 truss segment is scheduled for launch aboard the shuttle in the summer of 2001.
Circling the Earth every 92 minutes, the ISS is orbiting at an altitude with a high point of 248 statute miles and a low point of 230 statute miles. Since Zarya was launched last November, the station has completed more than 5,000 revolutions of the planet. Space Station viewing opportunities worldwide are available on the Internet at:
The next International Space Station status report will be on October 14. For further information, please contact the NASA Public Affairs Office at the Johnson Space Center, Houston, Texas, 281-483-5111.