Mir - WikiHQ

Mir (, ; ) was a space station operated in low Earth orbit from 1986 to 2001, first by the Soviet Union and later by the Russian Federation. Mir was the first modular space station and was assembled in orbit from 1986 to 1996. At the time it was the largest artificial satellite in orbit, only being succeeded by the International Space Station (ISS) after Mir<nowiki>'</nowiki>s deorbiting in 2001. The station served as a microgravity research laboratory in which crews conducted experiments in biology, human biology, physics, astronomy, meteorology, and spacecraft systems with a goal of developing technologies required for permanent occupation of space.

Mir was the first continuously inhabited long-term research station in orbit and previously held the record for the longest continuous human presence in space at 3,644 days, until it was surpassed by the ISS in 2010. It holds the record for the longest single human spaceflight, Valeri Polyakov, spending 437 days on the station between 1994 and 1995. Mir's typical crew size was 3, though larger short-term crews made an appearance, peaking at ten during STS-71. Occupied for twelve and a half years out of its fifteen-year lifespan, 105 cosmonauts and astronauts from 12 different nations visited the station, and conducted 80 spacewalks. at an inclination of 51.6°.

Initially, the station was operated by NPO Energia with subcontracting to KB Salyut. Following the dissolution of the Soviet Union, Mir was operated by the Russian Federal Space Agency (RKA). Most of the station's occupants were Soviet/Russian; through international collaborations such as the Interkosmos, Euromir and Shuttle–Mir programmes, the station was made accessible to space travellers from several Asian, European and North American nations. Mir was deorbited in March 2001 after funding was cut off. The cost of the Mir programme was estimated by former RKA General Director Yuri Koptev in 2001 as $4.2 billion over its lifetime (including development, assembly and orbital operation). , five of the ten longest human spaceflights ever were aboard Mir.

Origins

Mir was authorised by a 17 February 1976 decree, to design an improved model of the Salyut space stations. Four Salyut space stations had been launched since 1971, with three more being launched during Mirs development. It was planned that the station's core module (DOS-7 and the backup DOS-8) would be equipped with a total of four docking ports; two at either end of the station as with the Salyut stations, and an additional two ports on either side of a docking sphere at the front of the station to enable further modules to expand the station's capabilities. By August 1978, this had evolved to the final configuration of one aft port and five ports in a spherical compartment at the forward end of the station.

It was originally planned that the ports would connect to modules derived from the Soyuz spacecraft. These modules would have used a Soyuz propulsion module, as used in Soyuz and Progress, and the descent and orbital modules would have been replaced with a long laboratory module. Following a February 1979 governmental resolution, the programme was consolidated with Vladimir Chelomei's crewed Almaz military space station programme. The docking ports were reinforced to accommodate space station modules based on the TKS spacecraft. NPO Energia was responsible for the overall space station, with work subcontracted to KB Salyut, due to ongoing work on the Energia rocket, Salyut 7, Soyuz-T, and Progress spacecraft. KB Salyut began work in 1979, and drawings were released in 1982 and 1983. New systems incorporated into the station included gyrodyne flywheels (taken from Almaz), Kurs automatic rendezvous system, Luch satellite communications system, Elektron oxygen generators, and Vozdukh carbon dioxide scrubbers and the Salyut 5B digital flight control computer,

| rowspan="2" | Kvant-1 (Astrophysics Module)

| EO-2

| 31 March 1987

| Proton-K

| Soviet Union

| rowspan="2" | 80px

|- style="border-bottom: 3px solid gray"

| colspan="4" | The first expansion module to be launched, Kvant-1 consisted of two pressurised working compartments and one unpressurised experiment compartment. Scientific equipment included an X-ray telescope, an ultraviolet telescope, a wide-angle camera, high-energy X-ray experiments, an X-ray/gamma ray detector, and the Svetlana electrophoresis unit. The module also carried six gyrodynes for attitude control, in addition to life support systems including an Elektron oxygen generator and a Vozdukh carbon dioxide scrubber.

| rowspan="2" | Priroda (Earth Sensing Module)

| EO-21

| 26 April 1996

| Proton-K

| Russia

| rowspan="2" | 80px

|- style="border-bottom: 3px solid gray"

| colspan="4" | The seventh and final Mir module, Prirodas primary purpose was to conduct Earth resource experiments through remote sensing and to develop and verify remote sensing methods. The module's experiments were provided by twelve different nations, and covered microwave, visible, near infrared, and infrared spectral regions using both passive and active sounding methods. The module possessed both pressurised and unpressurised segments, and featured a large, externally mounted synthetic aperture radar dish.

Each module was fitted with external components specific to the experiments that were carried out within that module, the most obvious being the Travers antenna mounted to Priroda. This synthetic aperture radar consisted of a large dish-like framework mounted outside the module, with associated equipment within, used for Earth observations experiments, as was most of the other equipment on Priroda, including various radiometers and scan platforms. When the attitude of the station needed to be changed, the gyrodynes were disengaged, thrusters (including those mounted directly to the modules, and the VDU thruster used for roll control mounted to the Sofora girder) were used to attain the new attitude and the CMGs were reengaged.

The drag resulting from the residual atmosphere;
Vibratory acceleration caused by mechanical systems and the crew on the station;
Orbital corrections by the on-board gyroscopes (which spun at 10,000 rpm, producing vibrations of 166.67 Hz Normal air pressure on the station was 101.3 kPa (14.7 psi); the same as at sea level on Earth.

International cooperation

thumb|upright|[[Reinhold Ewald (right) and Vasily Tsibliyev in the core module during Ewald's visit to Mir]]

thumb|Scale model replica of the MIR Space Station at the Euro Space Center Belgium

Interkosmos

Interkosmos (m) was a Soviet space exploration programme which allowed members from foreign countries allied with the Soviet Union to participate in crewed and uncrewed space exploration missions. Participation was also made available to governments of countries such as France and India.

Only the last three of the programme's 14 missions consisted of an expedition to Mir but none resulted in an extended stay in the station:

Muhammed Faris – EP-1 (1987)
Aleksandr Panayatov Aleksandrov – EP-2 (1988)
Abdul Ahad Mohmand – EP-3 (1988)

European involvement

Various European astronauts visited Mir as part of several cooperative programmes, on both the Soyuz and the Space Shuttle:

Jean-Loup Chrétien – Aragatz (1988)
Helen Sharman – Project Juno (1991)
Franz Viehböck – Austromir '91 (1991)
Klaus-Dietrich Flade – Mir '92 (1992)
Michel Tognini – Antarès (1992)
Jean-Pierre Haigneré – Altair (1993)
Ulf Merbold – Euromir '94 (1994)
Thomas Reiter – Euromir '95 (1995)
Claudie Haigneré – Cassiopée (1996)
Reinhold Ewald – Mir '97 (1997)
Jean-François Clervoy – STS-84 (1997) France
Jean-Loup Chrétien – STS-86 (1997) France
Léopold Eyharts – Pégase (1998)
Jean-Pierre Haigneré – Perseus (1999) France
Ivan Bella – Stefanik (1999)

Shuttle–Mir program

thumb|The [[List of Mir visitors|seven NASA astronauts who carried out long-duration missions on Mir]]

In the early 1980s, NASA planned to launch a modular space station called Freedom as a counterpart to Mir, while the Soviets were planning to construct Mir-2 in the 1990s as a replacement for the station. Because of budget and design constraints, Freedom never progressed past mock-ups and minor component tests and, with the fall of the Soviet Union and the end of the Space Race, the project was nearly cancelled entirely by the United States House of Representatives. The post-Soviet economic chaos in Russia also led to the cancellation of Mir-2, though only after its base block, DOS-8, had been constructed. They also agreed, in preparation for this new project, that the United States would be heavily involved in the Mir programme as part of an international project known as the Shuttle–Mir Programme. The project, sometimes called "Phase One", was intended to allow the United States to learn from Russian experience in long-duration spaceflight and to foster a spirit of cooperation between the two nations and their space agencies, the US National Aeronautics and Space Administration (NASA) and the Russian Federal Space Agency (Roskosmos). The project prepared the way for further cooperative space ventures, specifically, "Phase Two" of the joint project, the construction of the ISS. The programme was announced in 1993; the first mission started in 1994, and the project continued until its scheduled completion in 1998. Eleven Space Shuttle missions, a joint Soyuz flight, and almost 1000 cumulative days in space for US astronauts occurred over the course of seven long-duration expeditions.

===Other visitors===

Toyohiro Akiyama – Kosmoreporter (1990)
A British con artist, Peter Rodney Llewellyn, almost visited Mir in 1999 on a private contract after promising US$100 million for the privilege.

Life on board

thumb|left|Time exposure of Mir passing over Earth's surface, May 1997.

thumb|right|A video tour of Mir from September 1996, during [[STS-79]]

thumb|right|A view of the interior of the [[Mir Core Module|core module's docking node, showing the crowded nature of the station.]]

Inside, the Mir was crowded with hoses, cables and scientific instruments—as well as articles of everyday life, such as photos, children's drawings, books and a guitar. It commonly housed three crew members, but was capable of supporting as many as six for short stays. The station was designed to remain in orbit for around five years; it remained in orbit for fifteen. As a result, NASA astronaut John Blaha reported that, with the exception of Priroda and Spektr, which were added late in the station's life, Mir did look used; which is a result of its aged condition.

Crew schedule

The time zone used on board Mir was Moscow Time (MSK; UTC+03). The windows were covered during night hours to give the impression of darkness because the station experienced 16 sunrises and sunsets a day. A typical day for the crew began with a wake-up at 08:00 MSK, followed by two hours of personal hygiene and breakfast. Work was conducted from 10:00 until 13:00, followed by an hour of exercise and an hour's lunch break. Three more hours of work and another hour of exercise followed lunch, and the crews began preparing for their evening meal at about 19:00. The cosmonauts were free to do as they wished in the evening, and largely worked to their own pace during the day. The station was also equipped with a supply of books and films for the crew to read and watch.

To prevent some of these effects, the station was equipped with two treadmills (in the core module and Kvant-2) and a stationary bicycle (in the core module); each cosmonaut was to cycle the equivalent of and run the equivalent of per day.

Hygiene

thumb|upright|One of the [[space toilets used aboard Mir]]

There were two space toilets (ASUs) on Mir, located in the core module and Kvant-2.

Sleeping in space

thumb|right|Cosmonaut [[Yury Usachov in his Kayutka]]

The station provided two permanent crew quarters, the Kayutkas, phonebooth sized boxes set towards the rear of the core module, each featuring a tethered sleeping bag, a fold-out desk, a porthole, and storage for personal effects. Visiting crews had no allocated sleep module, instead attaching a sleeping bag to an available space on a wall; US astronauts installed themselves within Spektr until a collision with a Progress spacecraft caused the depressurisation of that module.

Food and drink

Most of the food eaten by station crews was frozen, refrigerated or canned. Meals were prepared by the cosmonauts, with the help of a dietitian, before their flight to the station. The diet was designed to provide around of protein, of fat and of carbohydrates per day, in addition to appropriate mineral and vitamin supplements. Meals were spaced out through the day to aid assimilation. Moulds that develop aboard space stations can produce acids that degrade metal, glass and rubber. The moulds in Mir were found growing behind panels and inside air-conditioning equipment. The moulds also caused a foul smell, which was often cited as visitors' strongest impression. Researchers in 2018 reported, after detecting the presence on the International Space Station (ISS) of five Enterobacter bugandensis bacterial strains, none pathogenic to humans, that microorganisms on ISS should be carefully monitored to continue ensuring a medically healthy environment for the astronauts.

Some biologists were concerned about the mutant fungi being a major microbiological hazard for humans, and reaching Earth in the splashdown, after having been in an isolated environment for 15 years.

Station operations

Expeditions

Mir was visited by a total of 28 long-duration or "principal" crews, each of which was given a sequential expedition number formatted as EO-X. Expeditions varied in length (from the 72-day flight of the crew of EO-28 to the 437-day flight of Valeri Polyakov), but generally lasted around six months. The station was occupied for a total of four distinct periods; 12 March–16 July 1986 (EO-1), 5 February 1987 – 27 April 1989 (EO-2–EO-4), the record-breaking run from 5 September 1989 – 28 August 1999 (EO-5–EO-27), and 4 April–16 June 2000 (EO-28).

Leonid Kizim and Vladimir Solovyov first docked with Mir on 15 March 1986. During their nearly 51-day stay on Mir, they brought the station online and checked its systems. They unloaded two Progress spacecraft launched after their arrival, Progress 25 and Progress 26.

On 5 May 1986, they undocked from Mir for a day-long journey to Salyut 7. They spent 51 days there and gathered 400 kg of scientific material from Salyut 7 for return to Mir. While Soyuz T-15 was at Salyut 7, the uncrewed Soyuz TM-1 arrived at the unoccupied Mir and remained for 9 days, testing the new Soyuz TM model. Soyuz T-15 redocked with Mir on 26 June and delivered the experiments and 20 instruments, including a multichannel spectrometer. The EO-1 crew spent their last 20 days on Mir conducting Earth observations before returning to Earth on 16 July 1986, leaving the new station unoccupied.

The Soyuz TM-2 launch was the beginning of a string of 6 Soyuz launches and three long-duration crews between 5 February 1987 and 27 April 1989. This period also saw the first international visitors, Muhammed Faris (Syria), Abdul Ahad Mohmand (Afghanistan) and Jean-Loup Chrétien (France). With the departure of EO-4 on Soyuz TM-7 on 27 April 1989 the station was again left unoccupied.

Soyuz TM-9 launched EO-6 crew members Anatoly Solovyev and Aleksandr Balandin on 11 February 1990. While docking, the EO-5 crew noted that three thermal blankets on the ferry were loose, potentially creating problems on reentry, but it was decided that they would be manageable. Their stay on board Mir saw the addition of the Kristall module, launched 31 May 1990. The first docking attempt on 6 June was aborted due to an attitude control thruster failure. Kristall arrived at the front port on 10 June and was relocated to the lateral port opposite Kvant-2 the next day, restoring the equilibrium of the complex. Due to the delay in the docking of Kristall, EO-6 was extended by 10 days to permit the activation of the module's systems and to accommodate an EVA to repair the loose thermal blankets on Soyuz TM-9.

The EO-7 relief crew arrived aboard Soyuz TM-10 on 3 August 1990. The new crew arrived at Mir with quail for Kvant-2's cages, one of which laid an egg en route to the station. It was returned to Earth, along with 130 kg of experiment results and industrial products, in Soyuz TM-9.

The launch of Soyuz TM-19, carrying the EO-16 crew, was delayed due to the unavailability of a payload fairing for the booster that was to carry it, but the spacecraft eventually left Earth on 1 July 1994 and docked two days later. They stayed only four months to allow the Soyuz schedule to line up with the planned Space Shuttle manifest, and so Polyakov greeted a second resident crew in October, prior to the undocking of Soyuz TM-19, when the EO-17 crew arrived in Soyuz TM-20. Five weeks after Discovery departure, the EO-18 crew, including the first US cosmonaut Norman Thagard, arrived in Soyuz TM-21. The EO-17 crew left a few days later, with Polyakov completing his record-breaking 437-day spaceflight. During EO-18, the Spektr science module (which served as living and working space for American astronauts) was launched aboard a Proton rocket and docked to the station, carrying research equipment from America and other nations. The expedition's crew returned to Earth aboard following the first Shuttle–Mir docking mission, STS-71. Atlantis, launched on 27 June 1995, successfully docked with Mir on 29 June becoming the first US spacecraft to dock with a Russian spacecraft since the ASTP in 1975. The orbiter delivered the EO-19 crew and returned the EO-18 crew to Earth. The EO-20 crew were launched on 3 September, followed in November by the arrival of the docking module during STS-74.

On 21 February 1996, the two-man EO-21 crew was launched aboard Soyuz TM-23, and they were soon joined by US crew member Shannon Lucid, who was brought to the station by Atlantis during STS-76. During this mission, the first joint US spacewalk on Mir took place, deploying the Mir Environmental Effects Payload package for the docking module. Lucid became the first American to carry out a long-duration mission aboard Mir with her 188-day mission, which set the US single spaceflight record. During Lucid's time aboard Mir, Priroda, the station's final module, arrived as did French visitor Claudie Haigneré flying the Cassiopée mission. The flight aboard Soyuz TM-24 also delivered the EO-22 crew of Valery Korzun and Aleksandr Kaleri.

On 16 September 1996, with the launch of Atlantis and the STS-79 flight, Lucid's stay aboard Mir ended. During this fourth docking, John Blaha transferred onto Mir to take his place as resident US astronaut. His stay on the station improved operations in a number of areas, including transfer procedures for a docked space shuttle, "hand-over" procedures for long-duration American crew members, and "ham" amateur radio communications, as well as two spacewalks to reconfigure the station's power grid. Blaha spent four months with the EO-22 crew before returning to Earth aboard Atlantis on STS-81 in January 1997, at which point he was replaced by physician Jerry Linenger. During his flight, Linenger became the first American to conduct a spacewalk from a foreign space station and the first to test the Russian-built Orlan-M spacesuit alongside Russian cosmonaut Vasili Tsibliyev, flying EO-23. All three crew members of EO-23 performed a "fly-around" in Soyuz TM-25 spacecraft.

After these incidents, the US Congress and NASA considered whether to abandon the programme out of concern for the astronauts' safety, but NASA administrator Daniel Goldin decided to continue. Wolf spent 119 days aboard Mir with the EO-24 crew and was replaced during STS-89 with Andy Thomas, who carried out the last US expedition on Mir. The EO-25 crew arrived in Soyuz TM-27 in January 1998 before Thomas returned to Earth on the final Shuttle–Mir mission, STS-91.

Final days and deorbit

thumb|upright|Mir breaks up in Earth's atmosphere over the [[South Pacific Ocean|South Pacific on 23 March 2001.]]

Following the 8 June 1998 departure of Discovery, the EO-25 crew of Budarin and Musabayev remained on Mir, completing materials experiments and compiling a station inventory. On 2 July, Roskosmos director Yuri Koptev announced that, due to a lack of funding to keep Mir active, the station would be deorbited in June 1999.

Mirs deorbit was carried out in three stages. The first stage involved waiting for atmospheric drag to reduce the station's orbit to an average of . This began with the docking of Progress M1-5, a modified version of the Progress-M carrying 2.5 times more fuel in place of supplies. The second stage was the transfer of the station into a orbit. This was achieved with two burns of Progress M1-5's control engines at 00:32 UTC and 02:01 UTC on 23 March 2001. After a two-orbit pause, the third and final stage of the deorbit began with the burn of Progress M1-5's control engines and main engine at 05:08 UTC, lasting 22+ minutes. Atmospheric reentry (arbitrarily defined beginning at AMSL) occurred at 05:44 UTC near Nadi, Fiji. Major destruction of the station began around 05:52 UTC and most of the unburned fragments fell into the South Pacific Ocean around 06:00 UTC.

Visiting spacecraft

thumb|right|[[Soyuz TM-24 docked with Mir as seen from the during STS-79]]

Mir was primarily supported by the Russian Soyuz and Progress spacecraft and had two ports available for docking them. Initially, the fore and aft ports of the core module could be used for dockings, but following the permanent berthing of Kvant-1 to the aft port in 1987, the rear port of the new module took on this role from the core module's aft port. Each port was equipped with the plumbing required for Progress cargo ferries to replace the station's fluids and also the guidance systems needed to guide the spacecraft for docking. Two such systems were used on Mir; the rear ports of both the core module and Kvant-1 were equipped with both the Igla and Kurs systems, whilst the core module's forward port featured only the newer Kurs. Two models of Soyuz flew to Mir; Soyuz T-15 was the only Igla-equipped Soyuz-T to visit the station, whilst all other flights used the newer, Kurs-equipped Soyuz-TM. A total of 31 (30 crewed, 1 uncrewed) Soyuz spacecraft flew to the station over a 14-year period. As a result, when its cargo had been unloaded, each Progress was refilled with rubbish, spent equipment and other waste which was destroyed, along with the Progress itself, on reentry. The shuttles provided crew rotation of the American astronauts on station and carried cargo to and from the station, performing some of the largest transfers of cargo of the time. With a space shuttle docked to Mir, the temporary enlargements of living and working areas amounted to a complex that was the largest spacecraft in history at that time, with a combined mass of . The facility is now used to control the Russian Orbital Segment of the ISS. and the third was sold to an educational and entertainment complex in the US in 1997. Tommy Bartlett Exploratory purchased the unit and had it shipped to Wisconsin Dells, Wisconsin, where it became the centrepiece of the complex's Space Exploration wing.

Safety aspects

Ageing systems and atmosphere

In the later years of the programme, particularly during the Shuttle-Mir programme, Mir suffered from various systems failures. It had been designed for five years of use, but eventually flew for fifteen, and in the 1990s was showing its age, with frequent computer crashes, loss of power, uncontrolled tumbles through space and leaking pipes. Jerry Linenger in his book about his time on the facility says that the cooling system had developed tiny leaks too small and numerous to be repaired, that permitted the constant release of coolant. He says that it was especially noticeable after he had made a spacewalk and become used to the bottled air in his spacesuit. When he returned to the station and again began breathing the air inside Mir, he was shocked by the intensity of the smell and worried about the possible negative health effects of breathing such contaminated air. This daily dose is approximately that received from natural background radiation on Earth in two years. The radiation environment of the station was not uniform; closer proximity to the station's hull led to an increased radiation dose, and the strength of radiation shielding varied between modules; Kvant-2's being better than the core module, for instance.

The increased radiation levels pose a higher risk of crews developing cancer, and can cause damage to the chromosomes of lymphocytes. These cells are central to the immune system and so any damage to them could contribute to the lowered immunity experienced by cosmonauts. Over time, in theory, lowered immunity results in the spread of infection between crew members, especially in such confined areas. To avoid this only healthy people were permitted aboard. Radiation has also been linked to a higher incidence of cataracts in cosmonauts. Protective shielding and protective drugs may lower the risks to an acceptable level, but data is scarce and longer-term exposure will result in greater risks. coolant released by RORSAT nuclear powered satellites, small needles, and many other objects. These objects, in addition to natural micrometeoroids, posed a threat to the station as they could puncture pressurised modules and cause damage to other parts of the station, such as the solar arrays. Micrometeoroids also posed a risk to spacewalking cosmonauts, as such objects could puncture their spacesuits, causing them to depressurise. Meteor showers in particular posed a risk, and, during such storms, the crews slept in their Soyuz ferries to facilitate an emergency evacuation should Mir be damaged.