ISS logo. Photo: NASA

The International Space Station entered the 21st century operating normally with no problems reported as it orbits the Earth every 90 minutes. Flight controllers both in Houston and in Moscow reported a smooth, uneventful Y2K rollover of computer commanding involving the ISS as the year 2000 dawned last week.

Flight controllers continue to manage the charging of the batteries on the Zarya module and are watching over other systems on the station. Electrical power management continues to be the focus, with the Station operating on the power generated by four of six batteries inside Zarya. Batteries 1 and 2 remain disconnected from the electrical bus. Over the next two weeks, controllers plan to recharge battery 1 and place it in a backup, or standby mode, to used if necessary. The four batteries currently servicing Zarya are providing more than enough power for all ISS systems.

Flight controllers also reported a good test of the Kurs automatic docking system on Zarya. Some discrepancies were seen before the holidays on the system's relative velocity readings from possible electromagnetic interference (EMI) generated from other systems on the Station. Further testing of the system is likely prior to the launch of the Zvezda service module later this year. The Kurs system will be used during the final rendezvous and docking of the ISS with Zvezda about two weeks after it is launched from the Baikonur Cosmodrome in Kazakhstan.

The STS-101 shuttle mission was supposed to launch after Service Module's docking, but officials may fly Atlantis twice. Photo: NASA

ISS and Shuttle program managers are evaluating the possibility of flying a mission to the Station this spring in advance of the launch of Zvezda to take advantage of an opportunity to perform maintenance on some of Zarya's systems. If approved, the mission would extend the lifetime of those systems and accomplish some work in advance of another Shuttle flight to the Station this summer following the launch of Zvezda. The second mission is designed to prepare the service module for the arrival of its first resident crew later this year. A decision on whether to conduct the spring mission to the ISS is expected by the end of the month.

The International Space Station continues to operate in excellent shape as it orbits the Earth at an altitude of 246 by 234 statute miles. Since the launch of Zarya in November 1998, the ISS has completed almost 6,500 orbits.