When asked what the Mir team was doing as the station passed the critical mark of 137 miles (220 kilometers), Viktor Blagov, the MCC's deputy flight control chief was succinct: "Not much."

Mir's orbit is descending according to plan, and permanent communication with the station is being maintained. Analysis of incoming telemetric information shows all flight systems on the orbital outpost operating normally.

The Mir team will begin uploading commands into the station's main computer in the early hours of March 22 so it can be stabilized, Blagov said.

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It is expected that unburned fragments of the complex will fall into the Pacific between Australia and South America, with a center located at 44.2 degrees south latitude and 150.4 degrees west longitude on March 23 at around 1:30 a.m. EST (06:30 GMT; 9:30 a.m. Moscow time)

The fragments can fall in an area around the center, plus or minus 1,865 miles (3,000 kilometers) in length and about 62 miles (100 kilometers) in width.

The MCC will rely on Mir's thrusters to stabilize the station and orient it so that the engines of the Progress cargo ship, which was docked to the outpost in January, can fire against the direction of the station's current flight path.

Blagov insisted that either the main computer or its backup could execute these commands, even if power drops drastically onboard Mir as it has done in the past.

In December, MCC lost contact with Mir for more than 20 hours when its batteries suddenly lost power. This event shut down all 12 of the station's gyrodines -- rotating devices that keep the station oriented so its solar-power panels are aimed at the Sun. Such an alignment allows maximum electrical power generation for station systems and battery recharge. MCC has managed to retain contact with Mir during several subsequent power losses, but each of those incidents disabled its central computer for several days.

The station could go into an uncontrolled reentry if both Mir's main computer and its analog computers crash, according to Nikolai Ivanov, the MCC's chief ballistics expert.

Fearing the station's unstable batteries could cause similar glitches, MCC has devised a backup. If necessary, they will use the onboard computer and separate radio communications system on the Progress cargo ship.

These gyrodines have been, and will remain inactive while Mir's engines are used periodically to prepare the station for the Progress spacecraft's deorbiting burns, Ivanov said.

According to estimates of the Moscow-based Center for Analysis of Strategies and Technologies, there is 25-percent possibility that the station will spin out of control and reenter uncontrolled. Experts at the Moscow-based Center for Analysis of Strategies and Technologies believe that the lower Mir descends, the more difficult it will be to control its flight.

"It is easier to aim and calculate the descent trajectory at higher altitudes, whereas trying to orient the station at 137 miles (220 kilometers) may prove too be difficult," the center said in a written statement to SPACE.com earlier this month.

However, according to Ivanov, the MCC can keep the station under control as long as it remains above 137 miles. "Only at lower orbits can such problems begin," he said.

Once the reentry burns are completed, MCC personnel will hopefully just sit and watch what they hope will be a slow, if not painful, death of the station they have been running for more than a decade.

The programs MCC will upload will order the cargo ship's engines to fire the first of the braking impulses at 7:33 p.m. EST on March 22 (March 23 at 00:33 GMT; 3:33 a.m. Moscow time). This impulse will last some 20 minutes, according to Blagov.

The second impulse, which is also to last 20 minutes, is scheduled for 9:02 p.m. EST (March 23 at 02:02 GMT; 5:02 a.m. Moscow time) The third and final impulse will begin after 12:30 a.m. EST March 23 (05:30 GMT; 8.30 a.m. Moscow time) and last some 23 minutes.

The station will start disintegrating at an altitude of 50 to 70 miles (30 to 45 kilometers) and most of it should burn up during the fiery reentry. Around 1,500 fragments, weighing between 13 to 19 tons, are expected to survive the burning dash through Earth's atmosphere.

Mir's control flight chief, Vladimir Solovyov, will personally command the fiery plunge of this aged outpost into the Pacific Ocean more than 15 years after opening it with another Soviet cosmonaut, Leonid Kizim, in March of 1986.

Meanwhile at Mission Control, the large number of people who want to witness Mir's reentry from Korolyov is causing concerns of overcrowding.

According to MCC, the main Mir Mission Control room's balcony has limited space, so the main room used for International Space Station operations, along with other rooms, will also be used to accommodate the visitors.

"The Mission Control administration apologizes in advance for not being able to provide the corresponding conditions for the work of their representatives," the press service said. The center "is asking all accredited mass media to minimize the number of representatives they send to cover the last flight of the Mir space station."

"Only two representatives of each television company and one representative of each press edition, radio channel or photo edition will be admitted to the Mission Control halls," the MCC press office said.