Deorbit of Mir
Encyclopedia
The deorbit of Mir was the controlled atmospheric re-entry of the modular Russian space station Mir
carried out on March 23, 2001. Major components ranged from about 5 to 15 years in age, and included the Mir Core Module
, Kvant-1
, Kvant-2
, Kristall
, Spektr
, Priroda
, and Docking Module
. Although Russia
was optimistic about Mirs future, the country's commitments to the International Space Station
project left no funding to support Mir.
The deorbit was carried out in three stages. The first stage was waiting for atmospheric drag
to decay the orbit
an average of 220 kilometres (137 mi). This began with the docking of Progress M1-5
. The second stage was the transfer of the station into a 165 × 220 km (103 × 137 mi) orbit. This was achieved with two burns of the Progress M1-5's control engines at 00:32 UTC and 02:01 UTC on March 23, 2001. After a two-orbit pause, the third and final stage of Mirs deorbit began with the firing of Progress M1-5's control engines and main engine at 05:08 UTC, lasting a little over 22 minutes. The atmospheric re-entry at the altitude of 100 kilometres (62.1 mi) occurred at 05:44 UTC near Nadi
, Fiji
.
After the construction of the International Space Station began in 1998, Russian resources were split between the two stations. In 2000, Rosaviakosmos signed an agreement with MirCorp
to lease the station for commercial use, with the Soyuz TM-30
mission, intended to prepare the station for future use and conduct some commercial research, being flown later that year. This was to have been followed by more missions, including flights with space tourists
. However, due to the Russian government being concerned about MirCorp's ability to fund these missions, Rosaviakosmos decided against funding the continued operation of Mir.
In November 2000, Rosaviakosmos decided to deorbit Mir, and the next month Russian Prime Minister
Mikhail Kasyanov
signed an order to do so. By this stage Mir was well past the end of its design life, and Rosaviakosmos General Director Yuri Koptev
believed that "any of its systems could well fail at any time". Therefore it was decided to deorbit it whilst it was still functioning, rather than risk it falling back to Earth out of control, like Skylab
in 1979 and Salyut 7
in 1991, potentially dropping debris over a populated area.
The Mir Deorbit Monitoring Group, whose members were located in the Russian Mission Control Center (RMCC) and ESOC, was monitoring the whole dynamic phase of operation. Both RMCC control rooms in Moscow
were used for the massive media presence during the final stages of operation. Real-time reports from RMCC were provided via teleconference
during each deorbit burn to ESA spokespersons and representatives from national agencies. Video transmissions from RMCC were also made available to ESOC.
Two out of three Progress M1-5 propulsion firings, at approximately 90 minute intervals, were used to bring the perigee
of Mir down to an altitude of 160 kilometres above the Earth's surface. A tough contact with the atmosphere occurred at 100 km altitude, when some of the external light elements of Mir were torn off due to the rush through the rarefied air. At an altitude of 90 km sufficient heating from Mirs hull created a glowing halo of hot plasma. At about that time, the orbital complex broke apart and several of Mirs elements, surrounded by the plasma, were visible from Fiji
against the evening sky. Television pictures were transmitted around the world within a few minutes of the event. The entire process lasted from about 16:20 to 20:29 local solar time
. A short press conference was held in RMCC to cover the final stage of deorbit.
An official statement announced that Mir "ceased to exist" at 05:59:24 GMT. The final tracking of Mir was conducted by a United States Army
site on Kwajalein Atoll. The European Space Agency
, German Federal Ministry of Defence
and U.S. National Aeronautics and Space Administration also assisted with tracking Mir during its final orbit and reentry.
issued international warnings to ships and aircraft traveling in the South Pacific
area. However, deputy director of New Zealand's Maritime Safety Authority Tony Martin said that the chances of debris hitting ships would be pretty small. A similar situation occurred in Japan
, whose residents were warned to stay indoors during the forty-minute period when debris was most likely to fall. The local officials however admitted that the chances of an accident were very unlikely. The location of Mir announced after re-entry was 160°W 40°S with a debris spread of ±1,500 kilometres along track and ±100 kilometres laterally, reduced from the earlier estimate due to the steeper re-entry angle. On the same day, salvage hunters managed to retrieve some sizeable chunks of Mir out of the Pacific Ocean
.
Mir
Mir was a space station operated in low Earth orbit from 1986 to 2001, at first by the Soviet Union and then by Russia. Assembled in orbit from 1986 to 1996, Mir was the first modular space station and had a greater mass than that of any previous spacecraft, holding the record for the...
carried out on March 23, 2001. Major components ranged from about 5 to 15 years in age, and included the Mir Core Module
Mir Core Module
Mir , DOS-7, was the first module of the Soviet/Russian Mir space station complex, in low Earth orbit from 1986 to 2001. Generally referred to as either the core module or base block, the module was launched on 20 February 1986 on a Proton-K rocket from LC-200/39 at the Baikonur Cosmodrome...
, Kvant-1
Kvant-1
Kvant-1 was the second module of the Soviet space station Mir. It was the first addition to the Mir base block and contained scientific instruments for astrophysical observations and materials science experiments....
, Kvant-2
Kvant-2
Kvant-2 was the third module and second major addition to the Mir space station. Its primary purpose was to deliver new science experiments, better life support systems, and an airlock to Mir. It was launched on November 26, 1989 on a Proton rocket. It docked to Mir on December 6...
, Kristall
Kristall
The Kristall module was the fourth module and the third major addition to the Mir space station. As with previous modules, its configuration was based on the 77K module, and was originally named "Kvant 3". It was launched on May 31, 1990 on a Proton rocket...
, Spektr
Spektr
Spektr was the fifth module of the Mir Space Station. The module was designed for remote observation of Earth's environment containing atmospheric and surface research equipment...
, Priroda
Priroda
The Priroda module was the seventh and final module of the Mir Space Station. Its primary purpose was to conduct Earth resource experiments through remote sensing and to develop and verify remote sensing methods...
, and Docking Module
Mir Docking Module
The Stykovochnyy Otsek , GRAU index 316GK, otherwise known as the Mir docking module or SO, was the sixth module of the Russian space station Mir, launched in November 1995 aboard the...
. Although Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
was optimistic about Mirs future, the country's commitments to the International Space Station
International Space Station
The International Space Station is a habitable, artificial satellite in low Earth orbit. The ISS follows the Salyut, Almaz, Cosmos, Skylab, and Mir space stations, as the 11th space station launched, not including the Genesis I and II prototypes...
project left no funding to support Mir.
The deorbit was carried out in three stages. The first stage was waiting for atmospheric drag
Drag (physics)
In fluid dynamics, drag refers to forces which act on a solid object in the direction of the relative fluid flow velocity...
to decay the orbit
Orbital decay
Orbital decay is the process of prolonged reduction in the altitude of a satellite's orbit.This can be due to drag produced by an atmosphere due to frequent collisions between the satellite and surrounding air molecules. The drag experienced by the object is larger in the case of increased solar...
an average of 220 kilometres (137 mi). This began with the docking of Progress M1-5
Progress M1-5
Progress M1-5 was the Progress spacecraft which was launched by Russia in 2001 to deorbit the fifteen-year old Mir space station before it naturally fell from orbit, potentially landing in a populated area...
. The second stage was the transfer of the station into a 165 × 220 km (103 × 137 mi) orbit. This was achieved with two burns of the Progress M1-5's control engines at 00:32 UTC and 02:01 UTC on March 23, 2001. After a two-orbit pause, the third and final stage of Mirs deorbit began with the firing of Progress M1-5's control engines and main engine at 05:08 UTC, lasting a little over 22 minutes. The atmospheric re-entry at the altitude of 100 kilometres (62.1 mi) occurred at 05:44 UTC near Nadi
Nadi
Nadi is the third-largest conurbation in Fiji. It is located on the western side of the main island of Viti Levu, and had a population of 42,284 at the most recent census, in 2007. Nadi is multiracial with many of its inhabitants Indian or Fijian, along with a large transient population of foreign...
, Fiji
Fiji
Fiji , officially the Republic of Fiji , is an island nation in Melanesia in the South Pacific Ocean about northeast of New Zealand's North Island...
.
Background
MirCorp
MirCorp was a commercial space company created in 1999 by space entrepreneurs and involving the Russian space program that successfully undertook a number of firsts in the business of space exploration by using the aging Russian space station Mir as a commercial platform...
to lease the station for commercial use, with the Soyuz TM-30
Soyuz TM-30
Soyuz TM-30 , also known as Mir EO-28, was a Soyuz mission, the 39th and final human spaceflight to the Mir space station. The crew of the mission was sent by MirCorp, a privately funded company, to reactivate and repair the station...
mission, intended to prepare the station for future use and conduct some commercial research, being flown later that year. This was to have been followed by more missions, including flights with space tourists
Space tourism
Space Tourism is space travel for recreational, leisure or business purposes. A number of startup companies have sprung up in recent years, hoping to create a space tourism industry...
. However, due to the Russian government being concerned about MirCorp's ability to fund these missions, Rosaviakosmos decided against funding the continued operation of Mir.
In November 2000, Rosaviakosmos decided to deorbit Mir, and the next month Russian Prime Minister
Prime Minister of Russia
The Chairman of the Government of the Russian Federation The use of the term "Prime Minister" is strictly informal and is not allowed for by the Russian Constitution and other laws....
Mikhail Kasyanov
Mikhail Kasyanov
Mikhail Mikhailovich Kasyanov - was the Prime Minister of Russia from May 2000 to February 2004.He is the leader of the People's Democratic Union and an ex-member of the opposition coalition "The Other Russia".-Political career:...
signed an order to do so. By this stage Mir was well past the end of its design life, and Rosaviakosmos General Director Yuri Koptev
Yuri Koptev
Yuri Nikolayevich Koptev is a former General Director of the Russian Space Agency Roscosmos, serving in that role from 1992 to 2004.Beginning in 1965, he worked as an engineer at NPO Lavochkin....
believed that "any of its systems could well fail at any time". Therefore it was decided to deorbit it whilst it was still functioning, rather than risk it falling back to Earth out of control, like Skylab
Skylab
Skylab was a space station launched and operated by NASA, the space agency of the United States. Skylab orbited the Earth from 1973 to 1979, and included a workshop, a solar observatory, and other systems. It was launched unmanned by a modified Saturn V rocket, with a mass of...
in 1979 and Salyut 7
Salyut 7
Salyut 7 was a space station in low Earth orbit from April 1982 to February 1991. It was first manned in May 1982 with two crew via Soyuz T-5, and last visited in June 1986, by Soyuz T-15. Various crew and modules were used over its lifetime, including a total of 12 manned and 15 unmanned launches...
in 1991, potentially dropping debris over a populated area.
The process
Moscow
Moscow is the capital, the most populous city, and the most populous federal subject of Russia. The city is a major political, economic, cultural, scientific, religious, financial, educational, and transportation centre of Russia and the continent...
were used for the massive media presence during the final stages of operation. Real-time reports from RMCC were provided via teleconference
Teleconference
A teleconference or teleseminar is the live exchange and mass articulation of information among several persons and machines remote from one another but linked by a telecommunications system...
during each deorbit burn to ESA spokespersons and representatives from national agencies. Video transmissions from RMCC were also made available to ESOC.
Two out of three Progress M1-5 propulsion firings, at approximately 90 minute intervals, were used to bring the perigee
Perigee
Perigee is the point at which an object makes its closest approach to the Earth.. Often the term is used in a broader sense to define the point in an orbit where the orbiting body is closest to the body it orbits. The opposite is the apogee, the farthest or highest point.The Greek prefix "peri"...
of Mir down to an altitude of 160 kilometres above the Earth's surface. A tough contact with the atmosphere occurred at 100 km altitude, when some of the external light elements of Mir were torn off due to the rush through the rarefied air. At an altitude of 90 km sufficient heating from Mirs hull created a glowing halo of hot plasma. At about that time, the orbital complex broke apart and several of Mirs elements, surrounded by the plasma, were visible from Fiji
Fiji
Fiji , officially the Republic of Fiji , is an island nation in Melanesia in the South Pacific Ocean about northeast of New Zealand's North Island...
against the evening sky. Television pictures were transmitted around the world within a few minutes of the event. The entire process lasted from about 16:20 to 20:29 local solar time
Solar time
Solar time is a reckoning of the passage of time based on the Sun's position in the sky. The fundamental unit of solar time is the day. Two types of solar time are apparent solar time and mean solar time .-Introduction:...
. A short press conference was held in RMCC to cover the final stage of deorbit.
An official statement announced that Mir "ceased to exist" at 05:59:24 GMT. The final tracking of Mir was conducted by a United States Army
United States Army
The United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...
site on Kwajalein Atoll. The European Space Agency
European Space Agency
The European Space Agency , established in 1975, is an intergovernmental organisation dedicated to the exploration of space, currently with 18 member states...
, German Federal Ministry of Defence
Federal Ministry of Defence (Germany)
The Federal Ministry of Defence is a top-level federal agency, headed by the Federal Minister of Defence as a member of the Cabinet of Germany...
and U.S. National Aeronautics and Space Administration also assisted with tracking Mir during its final orbit and reentry.
Debris
At the time, Mir was the largest spacecraft ever to reenter the Earth's atmosphere, and there were concerns that sizeable pieces of debris, particularly from the docking assemblies, gyrodynes and external structure, could survive reentry. Amid debris fall, New ZealandNew Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
issued international warnings to ships and aircraft traveling in the South Pacific
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
area. However, deputy director of New Zealand's Maritime Safety Authority Tony Martin said that the chances of debris hitting ships would be pretty small. A similar situation occurred in Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
, whose residents were warned to stay indoors during the forty-minute period when debris was most likely to fall. The local officials however admitted that the chances of an accident were very unlikely. The location of Mir announced after re-entry was 160°W 40°S with a debris spread of ±1,500 kilometres along track and ±100 kilometres laterally, reduced from the earlier estimate due to the steeper re-entry angle. On the same day, salvage hunters managed to retrieve some sizeable chunks of Mir out of the Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
.