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MIR STATUS-Copied from below


The Progress M1 cargo ship during pre-launch processing at Site-254 in
Baikonur. Click to enlarge: 400x533 pixels, 104K. Copyright  2001 by
Anatoly Zak


Technician puts finishing touches on the solar panel of the Progress M1
spacecraft. Click to enlarge: 300x400 pixels, 48K. Copyright  2001 by
Anatoly Zak


During its final orbit, Mir will enter the communication range (shown in
green) of the Russian ground control stations. Around this time, the
Progress M1-5 cargo ship attached to Mir will perform a final deorbiting
burn. The first elements of the station will break off at the altitude
110-100 kilometers. The station itself is expected to disintegrate at the
altitude 90-70 kilometers. Estimated 30-35 tons of debris will survive
the reentry. 
By the fall of 2000, all efforts to raise enough funds to keep Mir
operational proved futile and no time remained to prepare more transport
ships to resupply the station in 2001. By the beginning of October 2000,
RKK Energia made a final decision to deorbit the outpost. Symbolically,
the company timed Mir's fiery reentry only after the station passes its
15th anniversary on February 20, 2001. The Progress M43 cargo ship
launched toward Mir in October, boosted the station's orbit, so it could
fly safely until beginning of 2001.

Mir wakes up in preparation for deorbiting 

2001 Jan. 9: In the first week of January 2001, ground controllers turned
on high-accuracy attitude control system onboard the Mir space station.
The computer controlled system, using electrically driven reaction
wheels, or gyrodines, would facilitate the upcoming docking with the last
supply ship scheduled to go to Mir before the station's deorbiting. 

The Progress M1-5 (Tail number 254) was prepared for blast off on January
18 from Site 1 in Baikonur Cosmodrome, Kazakhstan. (The original launch
date was Jan. 16) 

Unlike traditional rendezvous profile requiring two days between the
launch and the docking, the Progress M1-5 would spend four days
approaching the station on a fuel-conserving trajectory. The propellant
saved onboard the ship would give ground controllers more freedom for the
Mir deorbiting maneuver at the time planned at the end of February or
beginning of March. The propellant and engines onboard Progress M1 would
be used to perform the final deorbiting burn. 

Progress rollout 

2001 Jan. 16: The Progress M1-5 was rolled out to the launch pad in
Baikonur on Tuesday morning local time, January 16. The Soyuz launch
vehicle with the cargo ship under its payload fairing left the assembly
building at Site 2 at 05:00 Moscow Time and was lifted into vertical
position on the launch pad by 07:00.

The launch was scheduled for 09:56:26 Moscow Time (1:56 a.m. EST) on
January 18, 2001. 

Around ten minutes after the launch, the Progress M1-5 should reach its
initial 245x193-kilometer orbit.

If launched as scheduled, in the next four days, the cargo ship would
perform several engine firings, which would bring it into vicinity of the

Jan. 18: dual burn, starting at 13:46:35, and at 14:30:14 Moscow Time 
Jan. 19: one burn starting at 10:47 Moscow Time 
Jan. 20: one burn starting at 09:05:56 Moscow Time 
Jan. 21: dual burn, starting at 08:54:01 and at 09:49:57 Moscow Time 
The Progress M-43 cargo ship docked to Mir at the time was expected to
leave the station on January 19 at 06:00 a.m. Moscow Time.

The Progress M1-5 was scheduled to rendezvous with Mir at
297x313-kilometer orbit and dock with the station on January 22 at 10:58
Moscow Time.

Progress launch scrub 

2001 Jan. 18: As the launch team in Baikonur was preparing to start
fueling of the rocket booster to carry the Progress M1-5 to orbit,
electrical problems onboard Mir space station forced at least four-day
delay in the launch of the cargo ship toward the station. 

The voltage in Mir's electrical system unexpectedly dropped below the
acceptable limit, which caused an emergency shot down of the power-hungry
gyrodines in the station's highly accurate attitude control system. As a
result, Mir's orientation in space was disrupted and the station's
computerized flight control system, known as SUD, turned itself off.

The crisis developed when the station was out of range of the ground
control stations. The mission control discovered the problem during a
routine communication session, which took place between 04:15 and 04:30
Moscow Time on Thursday, January 18. The preparation for the launch of
the Progress M1-5 cargo ship scheduled for 09:56:26 Moscow Time was
immediately stopped. The fueling of the spacecraft's Soyuz booster had
not yet started by the time the launch was scrubbed.

Mission control representatives assured that despite energy problems, the
flow of telemetry from the station has never been interrupted and they
are able to communicate with the outpost.

It was expected to take four or five days for ground controllers to fully
reactivate attitude control system onboard Mir, the officials at the
mission control center in Korolev said. Representatives of the center
maintained that the situation is under control and no emergency actions,
such as sending a rescue crew to the station was necessary.

Progress launch reset for January 24

2001 Jan. 19: RKK Energia officials currently plan to make another
attempt to launch the Progress M1-5 cargo ship toward Mir on January 24.
This launch date will be contingent on the ability of the mission control
in Korolev to reboot the main computer onboard the station. The Salyut 5B
computer inside Mir's core module provides commands to the station's
working gyrodines, which orient the outpost in space. (Before the latest
control system shutdown, 10 out of 12 gyrodines were online)

After initial testing of the Salyut 5B on Thursday, the ground
controllers were convinced that the computer is in healthy condition and
the new set of instructions could be uploaded into the machine on Friday
and Saturday (Jan. 19 and 20). If this operation is successful, the
station's working gyrodines could be brought back online, restoring the
attitude control.

The officials now believe that high temperatures inside Kvant-2 module
most likely caused the energy supply failure onboard Mir on Jan. 18. In
the current phase of its orbit, Mir receives more then average exposure
to the Sun, while thermal control system onboard Kvant-2 experiences
problems. High temperatures in the module could cause abnormal
performance of the electrical batteries and they were automatically
shutdown by the onboard computers.

RKK Energia officials still hope that they will be able to restore full
control over the station and avoid sending an emergency crew to Mir.

Several factors complicate mission control's efforts to restore Mir's
normal operation, RKK Energia officials said. Since December the
technical problems with one of the transmitters onboard the core module
interrupt a flow of flight control data from the station. A backup
transmitter is available onboard Mir, however it has to be installed by
the crew.

On top of technical problems, the winter temperatures as low as -50C
degrees in the Russian Far East complicate the work of ground control
stations providing radio contact with Mir.

As ground controllers try to reactivate Mir's computer, the Progress M1-5
cargo ship remains on the launch pad in Baikonur. If the Progress M1-5
does take off on January 24, the Progress M43 spacecraft currently docked
to Mir will leave the station within 24 hours. The craft, however, will
remain in orbit until its successor docks with Mir. The Progress M43
carries air supplies and food rations, which could be used by the
emergency crew if situation requires.

In case Progress M1-5 had failed to dock with Mir, the mission control
could have tried to redock Progress M43 to the station to provide
additional food and air supplies to the crew.

Computer is back on line, but not the gyrodines 

2001 Jan. 22: The main computer onboard Mir space station is up and
running after several days of hiatus caused by the failure of the
electrical system onboard the station. On Friday, ground controllers
succeeded in reactivating the Salyut-5B computer responsible for the
attitude control of more than 100-ton orbital outpost. 

At the same time, the attempt by the mission control to activate six of
Mir's 12 electrically driven reaction wheels, known as gyrodines, failed
last week. Six gyrodines onboard Kvant-1 module slowed down and stopped
only few orbits after they were reactivated last week. There was no
attempt to restart six additional gyrodines installed on Kvant-2 module. 

Flight engineers currently evaluate what causes the gyrodines to brake,
however they do not expect to make another attempt to activate them
before the arrival of the cargo ship to the station. Without gyrodines,
the mission control will have to use the Mir's thrusters consuming
precious propellant to orient the station in space. 

The representatives of RKK Energia said that the problems with gyrodines
would not affect the planned docking between the station and the Progress
M1-5 cargo ship or the plans to de-orbit Mir at the beginning of March.
The officials also said that the temperature inside Mir modules gradually
normalizes after reaching its peak last week. The higher then normal
temperature inside Mir believed to be responsible for the fluctuation in
the station's electrical circuits and resulting shutdown of the control
system onboard. Currently, the temperature inside Mir's modules is as
high as 36C degrees. 

In the meantime, on Monday, the personnel at Baikonur Cosmodrome have
resumed a two-day process of preparing for the launch of the Progress
M1-5 cargo ship toward the station on January 24 at 07:28:42 Moscow Time.

Progress M1-5 blasts off

2001 Jan. 24: The Progress M1-5 spacecraft carrying 2,677 kilograms of
propellant for Mir's deorbiting maneuvers blasted off from Site 1 in
Baikonur Cosmodrome at 07:28:42 Moscow Time (11:28 p.m. EST on January
23). A three-stage Soyuz rocket delivered the spacecraft into its
intended 193 x 245-kilometer orbit. The Progress M1-5 separated from the
third stage at 07:37:31 Moscow Time (11:37 p.m. EST January 23).

Progress M1-5 planned rendezvous maneuvers: 

Ignition (Moscow time) Burn duration (seconds) Velocity increase (m/sec)
Post-maneuver altitude (km) 
Jan. 24, 11:34:22 20.2  1.41  - 
Jan. 24, 11:58:08 111.9 7.85 194 x 245 
Jan. 25, 08:14:33 6.1 2 197 x 268 
Jan. 26, 06:03:15 328.8 22.7 239 x 282 
Jan. 26, 06:49:20 95.9 6.8 257 x 297 


Further maneuvers of the craft will depend on the measurements conducted
by the BTsVK computer onboard Mir. The final orbit for the Progress M1-5
before docking is expected to be 260x299 kilometers, for Mir 296x313

The Progress was expected to arrive at the aft docking port on the Mir's
Kvant-1 module at 8:30 Moscow Time on January 27.

2001 Jan. 25: The Progress M-43 cargo ship, departed the Mir space
station today. The craft, which joined Mir last October, undocked from
Mir at 08:19:49 Moscow Time (12:19 a.m. EST) on January 25. The departure
of the Progress M-43 freed the aft docking port on the Kvant-1 module for
the arrival of the Progress M1-5, the fresh and last cargo ship to visit
the station. 

In the meantime, the Progress M1-5 completed its third orbit correction
maneuver in the course of its three-day chase of Mir. At 08:14:33 Moscow
Time (12:14 a.m. EST) on January 25, the spacecraft fired its engines,
which burnt for six seconds and added 2 meters per second to the craft's
orbital velocity. 

The Progress M1-5 was 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 40C degrees.

Progress M1-5 docks to Mir

2001 Jan. 27: The Progress M1-5 cargo ship, carrying propellant for Mir
deorbiting, docked to the station's Kvant-1 module at 08:34 Moscow Time
(12:34 a.m. EST) on January 27. The successful arrival of the Progress
M1-5 to the station made the manned emergency mission to Mir less likely.

Counting the Progress M1-5, total 110 spacecraft were launched toward Mir
during its 15-year history, including the additional modules, manned
Soyuz transport ships and US Space Shuttle. They conducted 121 dockings
with the station. 

2001 Jan. 29: The Progress M43 cargo spacecraft, which undocked from Mir
on January 25, reentered the earth atmosphere and burned up.

The spacecraft fired its braking engine at 05:12 Moscow Time on January
29 (9:12 p.m. EST on January 28) and according to calculations of the
mission control in Korolev, the ship's debris, which survived the
reentry, fell into a designated area of the ocean at 05:58 Moscow Time.

In the meantime, soon after docking between Mir and Progress M1-5, ground
controllers in Korolev sent Mir into a slow spin. Spin stabilization will
preserve the propellant onboard and evenly distribute the exposure of the
station's solar panels to the sun.

2001 Feb. 1: The Mir space station slowly loses its orbital altitude as
ground controllers preparing for the station's de-orbiting this March.

Although Russian space officials express full confidence in their ability
to control the station during its final days in orbit, they also say that
the wild fluctuations in the density of the Earth atmosphere make it more
difficult to predict exact date of Mir's reentry.

Currently, the regular peak of solar activity, which takes place
approximately every 11 years, causes the Earth atmosphere to "bulge,"
increasing atmospheric drag. As a result, low-orbiting spacecraft,
including Mir, spiral down toward denser atmosphere faster and less
evenly than usual.

According to high-ranking officials at RKK Energia, the company which
operates Mir, the station's altitude currently drops as little as 200
meters one day and as much as 650 meters on another, which complicates
the work of the team monitoring the station's orbit. 

On January 30, Mir descended to the altitude of 294 kilometers and it was
expected to go as low as 291-292 kilometers above the Earth surface on
Friday, February 1.

Currently ground controllers keep the station in the slow spin, as it
circles the Earth, to distribute evenly Mir's exposure to the sunlight.
However, around February 15, the mission control in Korolev expects to
switch Mir back to the active orientation, which will be maintained with
the use of small attitude control thrusters.

RKK Energia has ruled out the possibility of activating Mir's gyrodines,
the station's electrically powered reaction wheels, which allow highly
accurate orientation in space without use of onboard propellant. The
decision is dictated by the fact that Mir approaches the altitude of
around 260-270 kilometers, where the upper atmosphere is dense enough to
disturb gyrodines' super-sensitive performance.

Despite inactive gyrodines, the RKK Energia officials remain optimistic
that the amount of fuel onboard the station will be enough to deorbit the
station fully under control into a designated area of the Pacific Ocean,
east of New Zealand.

Mir marks its 15th anniversary

2001 Feb. 20: The day before the Mir space station marked its 15th
anniversary in orbit, the captains of the Russian space program defended
their decision to deorbit the pioneering outpost. 

On Monday, at the press-conference in Moscow, the Director of the Russian
Aviation and Space Agency, Rosaviacosmos, Yuri Koptev and Chief of RKK
Energia Yuri Semenov, argued that Mir long outlived its lifetime and the
controlled reentry in mid-March would be the safest way to conclude its

In the last few weeks, Communist members of the Russian Duma (parliament)
launched a last ditch attempt to prevent Mir's deorbiting. The opponents
of the decision to ditch Mir also held a demonstration in front of
Moscow's town hall calling for the conservation of the outpost at the
high orbit, before the funds for its further operation could be found. 
site by Arthur N1ORC(Amsat member #31468)
1050 HRS 3/17/01

Deorbit is set for March 22

2001 March 14: After weeks of uncertainty, the Russian space officials
set a definitive date of the Mir's fiery reentry for early hours on March
22. If everything goes as scheduled, the entire process of deorbiting
will take only 6 hours, during which Mir will make four final orbits
around the planet. In case of emergency, the ground controllers have 24
hours to solve problems and complete the operation.

According to Nikolai Anfimov, the chief of TsNIIMash, the main research
institution of the Russian space industry, the Progress cargo ship docked
to the station will fire its maneuvering trusters for the first time
around 04:00 Moscow Time on March 22. This and the second firing of the
Progress engines one orbit later, will leave the Mir on a
220-165-kilometer elliptical orbit. Mir will then circle the Earth
passively one more time, before entering its final orbit. The station's
third and last maneuver will start around 10:00 Moscow Time (2 a.m. EST)
with the firing of the Progress trusters and its main engine joining in
later in the burn. The reentry and disintegration of the station will
take place in the next thirty minutes.

Although the commands to fire the engines onboard Mir will be transmitted
during the station's pass within the range of Russian ground control
station, the outpost will leave the communication range at the time of
the engine shot down in the final maneuver. The ground control stations
in Ulan-Ude and Petrapavlovsk-Komchatskiy in the Russian Far East will be
the last to receive the telemetry from the doomed spacecraft.

2001 March 16: Mission control in Korolev plans to start active
orientation of Mir on Wednesday, March 21, or around 24 hours prior to
the station's scheduled deorbiting, Russian officials in mission control

With its attitude control up and running, Mir's solar arryas will start
tracking the Sun, allowing recharging the station's electrical battaries.
The deorbiting maneuvers, which are scheduled to start on early morning
Moscow Time March 22, will require reliable supply of energy to the
station's computers and propulsion system. 

The failure of the station's energy supply system is considered one of
the most likely failures, which might hit the mission during the
critically important deorbiting operations, said Vladimir Soloviev, the
head of Mir operations at mission control in Korolev. The failure of the
main computer on Mir is considered the second likely emergency situation.

According to Sloviev, in both scenarios, the flight controllers still
will be able to perform a controlled reentry 24 hours later using an
autonomous flight control system of the Progress cargo ship.

Currently, Mir is circling Earth slowly spinning in orbit, while its
digital control system functions in the so-called "indicator mode," where
ground controllers monitor the onboard computer, but do not send any
commands to the station's systems.

As of March 16, the average altitude of Mir orbit degraded by some 2.5
kilometers to 236 kilometers from 238.5 kilometers a day earlier.


Emergency crew 

A special emergency repair crew and the Soyuz TM spacecraft were
scheduled to be in a "standby mode" in case the Progress M1-5 carrying
critically needed propellant to Mir fails to dock, or a major malfunction
leaves the station uncontrollable from the ground.

According to RKK Energia management, the emergency crew would be able to
blast off toward Mir within 10 or 12 days after the decision to launch.
The Soyuz TM spacecraft (Tail number 206) for the emergency mission was
scheduled to be ready for fueling by January 18. Sources in Baikonur said
on January 16 that the launch date for the emergency crew was set for
February 10, 2001.

After around Feb. 22, 2001, the manned mission to Mir was ruled out as to
risky at that point.

If no emergency crew required for Mir deorbiting, the Soyuz TM (#206)
assigned to the emergency mission will be launched to the International
Space Station in April 2001. There, it will replace the older ship, which
has been docked to the ISS since November. The Soyuz TM spacecraft serves
as a "lifeboat" for the station crews and it should be rotated every six

Taxi crew replacement

So-called "taxi crews" are being prepared in Russia, to pilot Soyuz TM
ships to the ISS. After spending a few days onboard the station "taxi
crew" would return home onboard the the previous craft, leaving
"resident" crew of the station with a "fresh" lifeboat Soyuz TM. The
original plans called for the Russian female cosmonaut Nadezhda
Kuzhelnaya to be on the first taxi crew to the ISS. However, RKK
Energia's decision to fly Dennis Tito, a commercial passenger, with the
taxi crew will most likely require a change in the Russian part of the
crew. Since Tito speaks very little Russian, RKK Energia will assign
English-speaking cosmonauts on the crew. Kuzhelnaya is not among those,
sources said.

Mir reentry monitoring

In the meantime, the Russian Ministry of Defense is planning to monitor
the Mir deorbiting operation from its Navy vessel, the reliable sources

Soon after the last maneuver, Mir will begin to break up at the altitude
of about 80 kilometers. If everything goes as scheduled, the pieces,
which survive a fiery reentry into the Earth atmosphere will fall in the
Southern Pacific, east of New Zealand. This area of the ocean is
designated for this purpose by the international treaties and it was used
routinely for dumping the spacecraft, top Energia officials said. The
experts at the company estimated that from 20 to 35 tons of metal debris
would reach the surface of the planet. In its present orbital
configuration Mir weighs more than 100 tons. 

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