INTERNATIONAL SPACE STATION
STATUS REPORT #99-25
The International Space Station continues to operate in good health with flight controllers monitoring two minor problems. One is with a battery on Zarya and the other is with the backup communications system in Unity.
Battery cycling continues on the station with the exception of the restoration, or deep cycling, designed to maintain as long a life as possible on the electrical storage units. Plans are being formulated to resume this activity next week, once procedures are re-evaluated and approved. One of the six batteries is not usable and has been taken offline pending review of a procedure to potentially restore its functionality. This does not impact the electrical needs of equipment on board, as the Station's current systems can actually operate on as few as three batteries if electrical usage is managed diligently.
Earlier this week, controllers began troubleshooting a potential problem with the left-side antenna that is part of Unity's early communications system. The system serves as a backup to the Russian ground stations for communications to and from the ISS. If the left antenna is determined to need replacing, it can be done during a space walk on the next visit of the space shuttle to the ISS in December.
The International Space Station's orientation has Unity pointed toward Earth and Zarya pointed toward space in a slow spin about its axis to conserve fuel and maintain even temperatures on all surfaces.
The next shuttle flight to
visit the ISS is scheduled for December after the Zvezda living quarters
is docked in November. Shuttle launch updates are available on the
The International Space Station is in a slightly elliptical orbit with a high point of 257 statute miles and a low point of 238 statute miles. It has completed more than 3,594 orbits of Earth since its launch and circles the Earth once approximately every 92 minutes. As it passes overhead at dawn or dusk, the Station is easily visible from the ground.
Space Station viewing opportunities
for locations worldwide are available on the Internet at:
The next International Space Station status will be issued July 15.
Note: For further information, please contact the NASA Public Affairs Office at the Johnson Space Center, Houston, Texas, 281-483-5111.