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MIR de-orbit
- Subject: [sarex] MIR de-orbit
- From: K6due@xxxxxxx
- Date: Thu, 15 Mar 2001 02:21:00 EST
(The following is copied from MSNBC News)
NEXT WEEK, engineers at Russia’s Mission Control will issue the commands for
three precisely timed engine bursts that will send the abandoned 138-ton
space station streaking through Earth’s atmosphere over the Pacific. During
the descent, the intense re-entry heat is expected to blast Mir to pieces,
with up to 30 tons’ worth of flaming junk hitting the ocean about 2,400 miles
east of New Zealand. Some of the chunks could be as big as a compact car,
experts say.
Mir update
• Latest news: Mir flight director Vladimir Solovyov says deorbiting process
would begin March 21 or early March 22. Solovyov's primary concern is with
the station’s aging batteries, which could run down during the descent. That
would require an attached cargo ship to use all its fuel to bring the Mir
down.
• Low point of orbit: 150.6 miles (240.9 kilometers) as of Wednesday.
• Deorbiting maneuver: Estimated to begin March 21. Date may shift plus 2
days or minus 1 day.
Russia’s space agency is refining Mir’s final flight path every day, based
on its own tracking information as well as data from the United States and
other governments around the world. At the request of the Russian navy, the
trajectory has been shifted slightly so that the debris misses an uninhabited
group of French-controlled islands, flight director Vladimir Solovyov told
reporters Wednesday.
If everything goes according to plan, splashdown would occur at 9:21
a.m. Moscow time (1:21 a.m. ET) on March 22, the Interfax news agency
reported. But the timing is still shrouded in uncertainty: Fluctuations in
solar activity — or slight instabilities in Mir’s orbit — could shift the
schedule ahead or back. And Solovyov admitted that the trouble-plagued space
station could cause one last round of trouble.
“We anticipate two possible problems — the batteries running low ...
and the central computer’s failure,” he said at Mission Control in Korolyov,
just north of Moscow.
Battery failure led to a brief communication breakdown last December,
and since then Mission Control has switched off most of Mir’s systems to
conserve power. But even if a glitch arose aboard Mir in its final hours,
controllers could use backup systems on the cargo ship to push the space
station out of orbit, Solovyov said.
“It’s hard to predict at the moment, but our previous experience
demonstrates that we have put together quite a safe system,” he said. “At
least all the tests shows that it will work.”
Solovyov said countries such as China and Japan should have nothing to
fear from Mir’s fall. “The station will still be high up while it passes
over these countries, and no debris could hit them,” he said.
Just in case, the Russians have taken out a $200 million insurance
policy to cover potential damages.
FROM A JEWEL TO A JOKE
The Mir space station was once the crown jewel of the Soviet space
effort. Its first module was launched on Feb. 20, 1986, just weeks after the
Challenger explosion dealt NASA its worst setback. After the Soviet breakup
of the early 1990s, Mir housed the first extended Russian-American space
missions, serving as a model for International Space Station Alpha, which is
now under construction.
Russia's last space station notched many notable achievements, despite the
glitches of recent years:
• Longest single stay in space: Valery Polyakov, 437.7 days in 1994-95.
• Most cumulative time in space: Sergei Avdeyev, 747.6 days over 3 flights.
• Longest American space mission: Shannon Lucid's 188-day stay in 1996.
• Longest time in controlled flight: 15 years and counting, during which it
played host to 23,000 scientific experiments and more than 100 visitors from
a dozen nations.
Mir’s long history earned it a special place in the hearts of Russians — and
even Americans.
“Mir just represents an extraordinary technological achievement on the
part of Russia,” Bill McArthur, NASA’s director of operations for Russia,
told MSNBC.com.
But in the end, even the Russians conceded that the station had
outlived its usefulness.
“Of course we all feel sad that the station should be deorbited. But
this is the kind of measure we had to do, because it’s been in service for a
long time and it’s time to take it out,” said Valery Ryumin, a cosmonaut who
served as Mir’s first flight director. Ryumin is now deputy chief designer at
Energia, the company that manages the space station for the Russian
government.
.
15 years of Mir
Since 1986, Russia’s Mir space station has experienced moments of drama,
triumph and farce. Here are the high points and low points:
Jan. 24, 2001
Final cargo craft launched with fuel for Mir deorbiting.
Dec. 30, 2000
Russian prime minister signed order for Mir’s doom. MirCorp’s focus turned
to International Space Station.
Nov. 16, 2000
Russian space officials announced plan to junk Mir.
Oct. 17, 2000
Progress cargo craft launched to resupply Mir amid mixed signals about
station’s future.
Oct. 12, 2000
MirCorp said it was planning initial public offering. Flight plans for 2001
scaled back.
Aug. 8, 2000
MirCorp announced agreement for reality-based TV show involving flight to
Mir.
July 18,2000
MirCorp said it planned two long-duration space missions during 2001.
June 16, 2000
Two cosmonauts finished their mission and left behind an empty Mir. MirCorp
said financial manager Dennis Tito would pay an estimated $20 million for a
visit to Mir in 2001.
April 4, 2000
MirCorp-funded mission sent two cosmonauts to station for fix-up mission.
Jan. 20, 2000
Russia announced that Mir would stay in orbit with funding from
Amsterdam-based MirCorp
Aug. 28, 1999
Three cosmonauts abandoned Mir, ending what many thought was the station’s
final long-duration mission. Sergei Avdeyev set a record for most cumulative
time in space: 747.6 days.
July 17, 1999
Cargo craft was launched to Mir after resolution of Russian-Kazakh launch
dispute.
July 5, 1999
Russian booster rocket exploded after launch, setting off Russian-Kazakh
dispute that threatened Mir resupply.
June 8, 1998
NASA's Andrew Thomas left Mir and headed home on space shuttle, ending U.S.
role on the Russian space station.
March 3, 1998
Mir's crew was forced to put off a spacewalk after breaking three wrenches
while trying to unlock an outer hatch.
Feb. 26, 1998
A valve overheated in an air-purifying system, resulting in a little smoke
but no fire aboard Mir. The crew was in no danger, NASA said.
Dec. 17, 1997
The Mir crew launched an unmanned maintenance and inspection tool,
Inspector. The robotic camera on Inspector malfunctioned and the crew
abandoned attempts to fix it.
Aug. 25, 1997
Mir's primary and backup oxygen-generating systems broke down but were
quickly repaired.
Aug. 18, 1997
Mir’s main computer system failed, causing the spacecraft to lose its
orientation to the sun. It took a couple of days to bring the system back up,
and over the months that followed, the computer failed several more times.
July 16, 1997
Mir temporarily lost nearly all its power when the crew accidentally
disconnected a cable that delivered electricity to the ship’s orientation
system, which points its solar panels toward the sun.
July 14, 1997
Mir’s commander, Vasily Tsibliyev, complained of heart irregularities,
prompting mission controllers to remove him from a planned repair mission to
restore power - about half the station’s total - lost in the June collision.
July 3, 1997
Mir suffered another breakdown as gyroscopes that orient the station shut
down for the second time in two weeks.
July 1, 1997
Mir’s new oxygen generator had to be turned off because of an overheated
cooling line, forcing the three crewmen to rely on the air canisters that
caused a fire on the space station four months earlier.
June 25, 1997
A Russian supply ship crashed into the station during a test, causing one of
the six modules that comprise Mir to lose pressure. The crew closed the hatch
to shut the damaged Spektr module off from the rest of the Mir.
April 22, 1997
The temperature-control system began leaking harmful antifreeze, briefly
raising temperatures on parts of the station to above 86 degrees.
March 7, 1997
Both oxygen generators failed, forcing the crew to rely on canisters similar
to one that exploded in February. The crew repaired one unit, and a backup
was brought aboard a U.S. space shuttle in June.
Feb. 24, 1997
An oxygen canister burst into flames, filling the station with puffs of
vapor and smoke. Russian officials said the crew put out the fire using a wet
towel and a fire extinguisher.
Feb. 24, 1996
A spacecraft arrived at Mir to replace a crew of three stuck there six weeks
longer than planned when Moscow ran low on money.
March 14, 1995
NASA astronaut Norman Thagard was launched toward Mir on Russian Soyuz
spacecraft, marking the first mission in an era of shuttle-Mir cooperation.
Oct. 12, 1994
The automatic control and navigation systems were switched off temporarily
after power cells overloaded. The overload was because of heavy demand on the
life-support and air-cleaning units on the station, which was designed for a
maximum crew of five; a crew of six was on board.
Sept. 2, 1994
A supply ship loaded with food, water and equipment twice failed to dock. One
of the crew finally guided it manually.
March 18, 1992
Russia launched a manned rocket to relieve two cosmonauts, including
stranded flight engineer Sergei Krikalev, who had to stay aloft more than
five months longer than planned following the Soviet Union's collapse. To
save money and to satisfy Kazakh President Nursultan Nazarbayev, who demanded
that a Kazakh fly as a cosmonaut, Moscow authorities combined the missions
that were supposed to replace Krikalev with a joint Soviet-Austrian flight in
October 1991. But none of the crew members were qualified to replace him and
he was forced to remain in space.
July 17, 1990
During an excursion outside the space station to repair torn thermal
insulation on their Soyuz TM-9 capsule, two cosmonauts discovered they could
not close a hatch at the end of their spacewalk. They were subsequently able
to close it.
April 5, 1987
An unmanned research and equipment module, Kvant, failed to dock with Mir.
Tass, the former Soviet news agency, said the docking had to be aborted
"owing to an irregular functioning of the control system," but gave no
details.
Feb. 20, 1986
Mir was launched into orbit to become the base for a permanent manned Soviet
space station. It was named after the Russian word for peace.
A string of problems aboard Mir in 1997 — ranging from an onboard
fire to computer breakdowns to a near-fatal collision with a cargo ship —
took the shine off the jewel. Then the cash-strapped Russian government said
it had to cut off money for Mir to follow through on its financial
commitments to International Space Station Alpha.
Energia tried to keep the station alive with millions of dollars in
backing from Western investors, through a venture called MirCorp. The
investors funded the station’s final manned mission, which ended last June.
Since then, Mir has been guided remotely by Mission Control.
WHO KILLED MIR?
Last November, the Russians finally decided to sink Mir. MirCorp
President Jeffrey Manber complained that the decision was primarily motivated
by politics and economics rather than the station’s age.
“The Mir needed funds,” he told MSNBC.com. “There’s nothing
intuitively wrong with it. It’s like a car. If you maintain your car, it
runs. If you can’t maintain it, it does eventually get into mechanical
problems.”
Manber said he suspects that NASA pressured the Russians to sacrifice
their own spacecraft for the sake of the much more expensive Alpha station, a
sentiment shared by many Russians. In response, NASA officials say Mir’s fate
was a matter for the Russians alone to decide. But over the past year,
they’ve also strongly opposed the idea that Russia might shift any of its
scarce resources from Alpha to Mir.
Ryumin told MSNBC.com that Energia felt the station could have been
operated for years longer, but reluctantly agreed to let Mir go with three
conditions:
The station had to survive until its 15th birthday, “just to confirm
that the service life of the International Space Station would be no less
than the (planned) 15 years.” That condition was satisfied just a month ago.
Alpha’s Russian-built living quarters had to be in place and
occupied, because otherwise “we would be deprived of any presence in space.”
After a string of costly delays, that condition was satisfied last November
when the first crew moved into Alpha.
Finally, Mir should be taken out of orbit “in a very planned and
organized manner, so as not to present any threat to the safety and security
of citizens (on Earth).” That condition will be put to its final test next
week.
A protester holds a poster reading: "Let's Preserve Mir" during a rally in
front of the Russian Aviation and Space headquarters to mark the 15th
anniversary of the space station's launch. Many Russians consider Mir to be a
symbol of national pride.
LOOKING AHEAD, LOOKING BACK
The Russians are now turning their focus to Alpha, but Ryumin worries
that the new era won’t live up to Mir’s glory days.
“Of course the Russian space effort will be significantly reduced,
because when we had Mir, it was a purely Russian space station and we could
do whatever research we wanted to,” he said. “But now that we are part of
the International Space Station, we have such countries as the United States,
Japan, Canada and the European countries involved in that project, so the
effort of the Russian side will be much smaller and we’ll have to do
everything in a coordinated manner.”
Mir is only the latest in a string of orbital outposts:
• Salyut 1: 1971, three-man crew died during re-entry.
• Salyut 2: 1973, failed in orbit.
• Salyut 3: 1974-1975, occupied by one crew.
• Salyut 4: 1974-1977, two manned missions.
• Salyut 5: 1976-1977, last military space station.
• Salyut 6: 1977-1982, hosted 16 crews.
• Salyut 7: 1982-1991, first in-orbit construction.
• Mir: 1986-2001.
"Space Exploration" by J.K. Davies
Russia’s work on Alpha won’t make up for Mir’s loss, said Charles Vick, a
space policy analyst at the Washington-based Federation of American
Scientists. He said Energia’s top management “has got to ask the question,
‘Where’s my next dollar coming from, and my next contract to keep the people
at my enterprise working?’”
Looking beyond dollars and rubles, the transition from Mir to Alpha
carries an emotional sting for the Russian people: For the first time in
three decades, there will be no purely Russian outpost orbiting the Earth or
in development.
Mir’s defenders in Russia insist that the space station has to be
preserved as a symbol of national pride. But, as space agency chief Yuri
Koptev told reporters last month, “Flying a space station that threatens the
entire world isn’t the best way to show our greatness.”
For most Russians, there’s a sense of resignation as well as regret.
“We need a new space station because our Mir is very old,” said
Galina Kozyr, administrator of Moscow’s Memorial Museum of Cosmonautics.
“Some of the apparatus inside Mir is good, still working. But what to do?
What to do?”
After a pause, she answered her own question: “Nothing to do.”
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