2 p.m. CDT, Thursday, September 2, 1999
Mission Control Center, Houston, Texas

Following a test this week, International Space Station flight controllers are optimistic that one of the Station's batteries that has been disconnected from the electrical system for several weeks may be usable if needed in the future.

Designated Battery 1, it is one of six batteries on the Station. It was disconnected from the electrical system following a large degradation in its performance that was noted earlier this month. Previously, the battery's performance had been noted to be only slightly degraded. The Station's other five batteries are operating well and have been providing adequate power for all Station systems.

As part of their analysis of Battery 1, flight controllers for the Station in Moscow reconnected the battery to the Station's electrical system for one 92-minute orbit early this week. During the reconnection, it operated normally, although its performance appeared to remain slightly below average as was expected. Engineers believe the slight degradation in performance is due to one cell of the battery not operating properly, but that the larger performance problem which led to its disconnection earlier this month may have been an isolated event in the battery's associated electronics that will not recur.

Engineers are continuing to evaluate the battery and flight controllers may reconnect it in another test later this week for about three orbits, or about 4.5 hours, to gather more information. The evaluation and testing may lead controllers to deem the battery usable for future Station operations. Regardless of the outcome, plans are being formulated to replace the battery and its electronics with new equipment to be carried aboard the next Shuttle mission to visit the Station, mission STS-101 aboard Atlantis.

The Station remains in a slow spin to conserve fuel and maintain proper temperatures in an orbit with a high point of 249 statute miles and a low point of 236 statute miles. The complex has completed more than 4,440 orbits. Space Station viewing opportunities are available on the Internet at:

The next International Space Station status report will be issued Sept. 9. For more information, contact the NASA Public Affairs Office at the Johnson Space Center in Houston, Texas, at 281-483-5111.