Mir. Photo: NASA

The Progress M43 cargo ship departed the Mir space station today. The craft, which joined Mir last October, undocked from the aft port of the Kvant-1 module at 0519:49 GMT (12:19 a.m. EST).

The undocking opens the aft docking port on the Kvant-1 module on Mir for the arrival of the Progress M1-5, the fresh and last cargo ship to visit the station.

Progress M1-5 blasted off from Baikonur on January 24 and expected to dock with the station at about 0530 GMT (12:30 a.m. EST) on January 27.

Unlike the most Progress ships, which would be deorbited a few hours after their departure from the station, the Progress M43 will remain in orbit until January 28.

If Progress M1-5 fails to dock with Mir, the mission control in Korolev, might try to re-dock Progress M43 to the station. The cargo ship carries food rations and air supplies onboard, which the emergency crew could use, if it has to travel to Mir to facilitate the docking between Progress M1-5 and the station.

The Soyuz rocket ignites to launch the Progress M1-5 tug. Photo: Energia

In its turn, the Progress M1-5 carries 2,677-kilogram propellant cache critically needed for Mir deorbiting operations currently planned for the beginning or middle of March 2001.

In the meantime, the Progress M1-5 completed its third orbit correction maneuver in the course of its three-day chase of Mir. At 0514:33 GMT (12:14 a.m. EST) today, the spacecraft fired its engines, which burned for six seconds and added two meters per second to the craft's orbital velocity. The Progress M1-5 is expected to complete at least two more orbit corrections on January 26 before its final rendezvous with Mir.

The representatives of the mission control in Korolev said that Mir remained in good shape for docking, although the temperature inside Kvant-2 module was as high as 40 degrees C. The higher than normal temperature onboard Mir caused an emergency shutdown of the station's control system last week and a six-day delay with the launch of the Progress M1-5 spacecraft.

Presently, Mir orbits the Earth under almost 24 hours of daylight and the thermal control system onboard the station experiences problems keeping the temperature down. However, the ground controllers believe that the temperature inside Mir is acceptable for present flight control mode. Mir is currently maintaining its orientation in space with the small attitude control thrusters. The station's 12 gyrodines, the electrically powered reaction wheels, remain inactive.