Wednesday March 21 4:18 PM ET Russia Readies Mir for Ocean Dump By VLADIMIR ISACHENKOV, Associated Press Writer MOSCOW (AP) - The Mir space station reached a lower orbit Wednesday, allowing Russian space officials to start steadying the slowly rolling craft and charging its unstable batteries - the final preparations for dumping it into the South Pacific this week. The success of the de-orbiting hinges on whether Mission Control can control the delicate operations on the station as it circles 132 miles above Earth - the orbit designated as the starting point for the descent process that is to end with re-entry Friday, said Mission Control spokesman Valery Lyndin. ``The next step will be bringing Mir to a stable position on Thursday,'' he said. The key will be to orient the station so its solar panels can soak up the maximum amount of energy possible to charge the batteries. The 15-year-old Mir, which officials say is decrepit and too expensive to operate any more, has been left to drift in a slow rolling motion since the end of January to save its batteries and fuel for re-entry. It slowly descended on its own into the new orbit over several weeks. Mission Control officials have acknowledged that switching on its computer-controlled orientation system could be tricky. In December, Mission Control lost contact with the station for more than 20 hours because the batteries suddenly lost power. Space officials have managed to retain contact with Mir during several subsequent power losses, but each of those incidents disabled its central computer for days. Mission Control experts have worked out a backup - using the onboard computer and separate radio communications of the Progress cargo ship docked at the station. If Mir's position can't be stabilized, the re-entry process will become uncontrollable. At around 4 a.m. Thursday Moscow time (8 p.m. EST Wednesday), Mission Control will begin sending computer commands to switch on Mir's orientation system and fire thrusters to steady the station, a process that will take several hours, he said. If the process goes smoothly, Progress will fire its engines twice Friday for about 20 minutes, at around 3:30 a.m. (7:30 p.m. EST Thursday) and 5 a.m. (9 p.m. EST) during consecutive orbits. That will slow the station and change its orbit from round to elliptical. Then, at around 8 a.m. Moscow time (midnight EST), Progress engines will fire one last time for 23 minutes to send the station hurtling into the South Pacific between Australia and Chile. Most of Mir is expected to burn up in the atmosphere during re-entry, but up to 27.5 tons of debris are expected to reach Earth in an oblong dump zone centered roughly around 44 degrees south latitude and 150 degrees west longitude. On Wednesday, Chile expressed its ``concern and displeasure'' over the dumping, ordering its ambassador to Russia to reject an invitation by Moscow to monitor Mir's fall from the space center. As a precaution, all flights between Chile and Tahiti were suspended for Thursday and Friday, Chilean Foreign Minister Soledad Alvear said. Space officials were confident of a safe descent, pointing to their experience in dumping dozens of Progress ships and other spacecraft into the same area of the Pacific. But the 143-ton station is by far the heaviest spacecraft ever dumped, and its size and shape make it difficult to exactly predict the re-entry. ``It's an experiment,'' Mir cosmonaut Valery Ryumin said on Echo of Moscow radio. ``No one has experience at this.''