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57-509: The Kvant-1 module contained scientific instruments for astrophysical observations and materials science experiments. It was used to conduct research into the physics of active galaxies, quasars and neutron stars and it was uniquely positioned for studies of the Supernova SN 1987A . Furthermore, it supported biotechnology experiments in anti-viral preparations and fractions. Some additions to Kvant-1 during its lifetime were solar arrays and

114-590: A Proton rocket . It docked to Mir on December 6. Its control system was designed by the NPO "Electropribor" ( Kharkiv , Ukraine ). Kvant-2 was the first Mir module based on the TKS spacecraft (77k module). Kvant-2 was divided into three compartments. They were the EVA airlock, the instrument/cargo compartment, and the instrument/experiment compartment. The instrument/cargo compartment could be sealed off and act as an extension or

171-759: A back-up to the airlock. Before Kvant-2 docked to the station, EVAs had to be carried by depressurizing the docking node on the Core Module . Kvant-2 also carried the Soviet version of the Manned Maneuvering Unit for the Orlan space suit . It delivered the Salyut 5B computer which was an improvement over the Argon 16B computer already on the station. Kvant-2 had a system for regenerating water from urine and

228-403: A blue supergiant producing a supernova was considered surprising, and the confirmation led to further research which identified an earlier supernova with a blue supergiant progenitor. Some models of SN 1987A's progenitor attributed the blue color largely to its chemical composition rather than its evolutionary stage, particularly the low levels of heavy elements. There was some speculation that

285-412: A core-collapse supernova, which should result in a neutron star given the size of the original star. The neutrino data indicate that a compact object did form at the star's core, and astronomers immediately began searching for the collapsed core. The Hubble Space Telescope took images of the supernova regularly from August 1990 without a clear detection of a neutron star. A number of possibilities for

342-576: A dusty ejecta on the basis of an IR excess alone. An independent Australian team advanced several argument in favour of an echo interpretation. This seemingly straightforward interpretation of the nature of the IR emission was challenged by the ESO group and definitively ruled out after presenting optical evidence for the presence of dust in the SN ejecta. To discriminate between the two interpretations, they considered

399-422: A five-neutrino burst, but this is generally not believed to be associated with SN 1987A. The Kamiokande II detection, which at 12 neutrinos had the largest sample population, showed the neutrinos arriving in two distinct pulses. The first pulse at 07:35:35 comprised 9 neutrinos over a period of 1.915 seconds. A second pulse of three neutrinos arrived during a 3.220-second interval from 9.219 to 12.439 seconds after

456-462: A function of time, after the explosion of a type II supernova such as SN 1987A is produced by the energy from radioactive decay . Although the luminous emission consists of optical photons, it is the radioactive power absorbed that keeps the remnant hot enough to radiate light. Without the radioactive heat, it would dim quickly. The radioactive decay of Ni through its daughters Co to Fe produces gamma-ray photons that are absorbed and dominate

513-451: Is 0.808 arcseconds in radius. The time light traveled to light up the inner ring gives its radius of 0.66 (ly) light years . Using this as the base of a right angle triangle and the angular size as seen from the Earth for the local angle, one can use basic trigonometry to calculate the distance to SN 1987A, which is about 168,000 light-years. The material from the explosion is catching up with

570-431: Is a compact object in the supernova remnant, but no material to fall onto it, it would be too dim for detection. A fourth hypothesis is that the collapsed core became a quark star . In 2019, evidence was presented for a neutron star inside one of the brightest dust clumps, close to the expected position of the supernova remnant. In 2021, further evidence was presented of hard X-ray emissions from SN 1987A originating in

627-544: Is a typical representative of its class then the derived mass of the warm dust formed in the debris of core collapse supernovae is not sufficient to account for all the dust observed in the early universe. However, a much larger reservoir of ~0.25 solar mass of colder dust (at ~26 K) in the ejecta of SN 1987A was found with the infrared Herschel Space Telescope in 2011 and confirmed with the Atacama Large Millimeter Array (ALMA) in 2014. Following

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684-527: Is absorbed by the dense ejecta close to the center, is responsible for a comparable increase in the optical flux from the supernova remnant in 2001–2009. This increase of the brightness of the remnant reversed the trend observed before 2001, when the optical flux was decreasing due to the decaying of Ti isotope. A study reported in June 2015, using images from the Hubble Space Telescope and

741-488: The European Southern Observatory (ESO). In particular, the ESO team reported an infrared excess which became apparent beginning less than one month after the explosion (March 11, 1987). Three possible interpretations for it were discussed in this work: the infrared echo hypothesis was discarded, and thermal emission from dust that could have condensed in the ejecta was favoured (in which case

798-500: The Salyut 6 and Salyut 7 space stations (and temporarily attached TKS-derived space station modules like Kosmos 1267 , Kosmos 1443 and Kosmos 1686 ) it became the first space station module to be attached semi-permanently to the first modular space station in the history of space flight. Kvant-1 was originally planned to be docked to the Salyut 7 space station, the plans however evolved to launch to Mir , initially considered on board

855-560: The Sofora and Rapana girders. The Kvant-1 module was based on the TKS spacecraft and was the first, experimental version of a planned series of '37K' type modules. The 37K modules featured a jettisonable TKS-E type propulsion module, also called the Functional Service Module (FSM). The control system of Kvant-1 had been developed by NPO "Electropribor" ( Kharkiv , Ukraine ). After previous engineering tests with

912-558: The Very Large Telescope taken between 1994 and 2014, shows that the emissions from the clumps of matter making up the rings are fading as the clumps are destroyed by the shock wave. It is predicted the ring would fade away between 2020 and 2030. These findings are also supported by the results of a three-dimensional hydrodynamic model which describes the interaction of the blast wave with the circumstellar nebula. The model also shows that X-ray emission from ejecta heated up by

969-410: The stellar wind of the progenitor. These rings were ionized by the ultraviolet flash from the supernova explosion, and consequently began emitting in various emission lines. These rings did not "turn on" until several months after the supernova and the process can be very accurately studied through spectroscopy. The rings are large enough that their angular size can be measured accurately: the inner ring

1026-423: The "missing" neutron star were considered. First, that the neutron star may be obscured by surrounding dense dust clouds. Second, that a pulsar was formed, but with either an unusually large or small magnetic field. Third, that large amounts of material fell back on the neutron star, collapsing it further into a black hole . Neutron stars and black holes often give off light as material falls onto them. If there

1083-596: The EO-2 crew, which had already docked on the front port with the Soyuz TM-2 spacecraft. On April 9, Kvant-1 achieved a soft dock with the aft port on Mir. However, the Kvant-1 was not able to achieve a hard dock which meant that the two spacecraft were only loosely connected – in this configuration, Mir could not orient itself or else damage would occur. The EO-2 crew conducted an emergency EVA on April 11 to investigate

1140-674: The Kvant-FSM, tests of the onboard systems of Kvant-1 were conducted until the end of April. May was spent in preparation for the extension of the electrical power with activities which required little electricity, like medical experiments and Earth resources photography – much-needed additional electrical power would enable experiments like the Korund 1-M kiln, which was used to conduct melts lasting several days, and to power Kvant-1's gyrodines, needed for astronomical observations. For this, Kvant had carried stowed solar arrays, which were attached to

1197-633: The Mir base block during an EVA on June 12. With the testing of Kvant-1 concluded, additional solar panels installed and Kvant's gyrodines available, a major step in the construction of the Mir space station was achieved. The X-ray telescope onboard Kvant-1 could start with a bang: it was uniquely placed to study Supernova SN 1987A in the Large Magellanic Cloud, the peak of its light reaching Earth in May 1987. The cosmonauts onboard Mir could examine

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1254-688: The Progress tanker spacecraft to Mir's storage tanks. This increased weight again, forcing the FGB to have its propellant load reduced to 60% in the high-pressure tanks and empty low-pressure tanks. With a reported total launch weight varying between 20,600 and 22,797 kilograms (45,415 and 50,259 lb), Kvant-1 was supposedly at that time the heaviest payload lifted by Proton, requiring special custom modifications to its launch vehicle. Kvant-1 consisted of two pressurized working compartments, one unpressurized experiment compartment and one small airlock for access to

1311-529: The Soviet Buran space shuttle, which finally changed to a launch to Mir by the Proton-K rocket. The Kvant spacecraft represented the first use of a new kind of Soviet space station module, designated 37K. An order authorising the beginning of development was issued on 17 September 1979. The basic 37K design consisted of a 4.2 m diameter pressurised cylinder with a docking port at the forward end. It

1368-406: The beginning of the first pulse. Although only 25 neutrinos were detected during the event, it was a significant increase from the previously observed background level. This was the first time neutrinos known to be emitted from a supernova had been observed directly, which marked the beginning of neutrino astronomy . The observations were consistent with theoretical supernova models in which 99% of

1425-482: The central region of the Supernova 1987A (SN 1987A) remnants. These emission lines, discernible only near the remnant's core, were analyzed using photoionization models. The models indicate that the observed line ratios and velocities can be attributed to ionizing radiation originating from a neutron star illuminating gas from the inner regions of the exploded star. Much of the light curve , or graph of luminosity as

1482-420: The confirmation of a large amount of cold dust in the ejecta, ALMA has continued observing SN 1987A. Synchrotron radiation due to shock interaction in the equatorial ring has been measured. Cold (20–100K) carbon monoxide (CO) and silicate molecules (SiO) were observed. The data show that CO and SiO distributions are clumpy, and that different nucleosynthesis products (C, O and Si) are located in different places of

1539-631: The crew installed the VDU propulsion unit on the end of the Sofora girder. It was delivered earlier by Progress M-14 . The VDU was designed to increase the station's attitude control capability. The then-six-year-old VDU propulsion unit was finally replaced in April 1998 by a new one that was delivered by Progress M-38. In September 1993, the Rapana girder was constructed on Kvant-1 during two EVAs. The Rapana girder

1596-471: The ejecta, indicating the footprints of the stellar interior at the time of the explosion. Kvant-2 Kvant-2 ( Russian : Квант-2 ; English : Quantum-II/2 ) (77KSD, TsM-D, 11F77D) 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

1653-414: The energy of the collapse is radiated away in the form of neutrinos. The observations are also consistent with the models' estimates of a total neutrino count of 10 with a total energy of 10 joules, i.e. a mean value of some dozens of MeV per neutrino. Billions of neutrinos passed through a square centimeter on Earth. The neutrino measurements allowed upper bounds on neutrino mass and charge, as well as

1710-596: The entire Mir complex. As the gyrodines were powered by electricity, they also reduced significantly the amount of attitude control propellant needed by the Mir base block's control thrusters – saving 15 tons of propellant in the first two years. They did, however, use a great deal of electricity – the average consumption of the Kvant-1 module was estimated to have been 6.90 kW. Kvant-1 was originally intended to be launched and docked to Salyut 7 , but delays forced it to be launched to Mir instead. Kvant-1 did not have any propulsion systems of its own and to reach Mir, Kvant-1

1767-591: The estimated temperature at that epoch was ~ 1250 K, and the dust mass was approximately 6.6 × 10   M ☉ ). The possibility that the IR excess could be produced by optically thick free-free emission seemed unlikely because the luminosity in UV photons needed to keep the envelope ionized was much larger than what was available, but it was not ruled out in view of the eventuality of electron scattering, which had not been considered. However, none of these three groups had sufficiently convincing proofs to claim for

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1824-419: The exploding star during 115 sessions between June and September 1987. In January 1991, support structures that were designed to hold solar arrays were installed on Kvant-1. In July 1991, the crew constructed the Sofora girder during four EVAs. The Sofora girder was designed to test new construction techniques, mount a propulsion unit, and act as a place to hold experiments outside the station. In September 1992,

1881-571: The fire died out. The smoke remained thick for forty-five minutes after the fire was extinguished. After the respirators ran out of oxygen and the smoke began to clear the crew switched to using filter masks. SN 1987A SN 1987A was a type II supernova in the Large Magellanic Cloud , a dwarf satellite galaxy of the Milky Way . It occurred approximately 51.4 kiloparsecs (168,000 light-years ) from Earth and

1938-412: The first opportunity to confirm by direct observation the radioactive source of the energy for visible light emissions, by detecting predicted gamma-ray line radiation from two of its abundant radioactive nuclei. This proved the radioactive nature of the long-duration post-explosion glow of supernovae. In 2019, indirect evidence for the presence of a collapsed neutron star within the remnants of SN 1987A

1995-406: The heating and thus the luminosity of the ejecta at intermediate times (several weeks) to late times (several months). Energy for the peak of the light curve of SN1987A was provided by the decay of Ni to Co (half life of 6 days) while energy for the later light curve in particular fit very closely with the 77.3-day half-life of Co decaying to Fe. Later measurements by space gamma-ray telescopes of

2052-428: The implication of the presence of an echoing dust cloud on the optical light curve, and on the existence of diffuse optical emission around the SN. They concluded that the expected optical echo from the cloud should be resolvable, and could be very bright with an integrated visual brightness of magnitude 10.3 around day 650. However, further optical observations, as expressed in SN light curve, showed no inflection in

2109-413: The light curve at the predicted level. Finally, the ESO team presented a convincing clumpy model for dust condensation in the ejecta. Although it had been thought more than 50 years ago that dust could form in the ejecta of a core-collapse supernova, which in particular could explain the origin of the dust seen in young galaxies, that was the first time that such a condensation was observed. If SN 1987A

2166-401: The material expelled during both its red and blue supergiant phases and heating it, so we observe ring structures about the star. Around 2001, the expanding (>7,000 km/s) supernova ejecta collided with the inner ring. This caused its heating and the generation of x-rays—the x-ray flux from the ring increased by a factor of three between 2001 and 2009. A part of the x-ray radiation, which

2223-625: The number of flavors of neutrinos and other properties. For example, the data show that the rest mass of the electron neutrino is < 16 eV/c at 95% confidence, which is 30,000 times smaller than the mass of an electron . The data suggest that the total number of neutrino flavors is at most 8 but other observations and experiments give tighter estimates. Many of these results have since been confirmed or tightened by other neutrino experiments such as more careful analysis of solar neutrinos and atmospheric neutrinos as well as experiments with artificial neutrino sources. SN 1987A appears to be

2280-411: The problem. The crew found a piece of debris, probably a trash bag, that was left by Progress 28. After removing it, Kvant-1 was finally able to achieve a hard dock with the station on the same day. The Kvant-FSM, which contained the now unneeded propulsion of the Kvant-1 module, was finally jettisoned on April 12, revealing Kvant-1's rear docking port. After finally achieving hard-dock and jettisoning of

2337-517: The pulsar wind nebula. The latter result is supported by a three-dimensional magnetohydrodynamic model, which describes the evolution of SN 1987A from the SN event to the present, and reconstructs the ambient environment, predicting the absorbing power of the dense stellar material around the pulsar. In 2024, researchers using the James Webb Space Telescope (JWST) identified distinctive emission lines of ionized argon within

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2394-481: The radioactive power from their decays in the 1987A light curve have measured accurate total masses of the Ni, Ni, and Ti created in the explosion, which agree with the masses measured by gamma-ray line space telescopes and provides nucleosynthesis constraints on the computed supernova model. The three bright rings around SN 1987A that were visible after a few months in images by the Hubble Space Telescope are material from

2451-503: The ring interactions of the ejecta began to contribute significantly to the total light curve. This was noticed by the Hubble Space Telescope as a steady increase in luminosity 10,000 days after the event in the blue and red spectral bands. X-ray lines Ti observed by the INTEGRAL space X-ray telescope showed that the total mass of radioactive Ti synthesized during the explosion was 3.1 ± 0.8 × 10 M ☉ . Observations of

2508-418: The shock will be dominant very soon, after which the ring would fade away. As the shock wave passes the circumstellar ring it will trace the history of mass loss of the supernova's progenitor and provide useful information for discriminating among various models for the progenitor of SN 1987A. In 2018, radio observations from the interaction between the circumstellar ring of dust and the shockwave has confirmed

2565-644: The shockwave has now left the circumstellar material. It also shows that the speed of the shockwave, which slowed down to 2,300 km/s while interacting with the dust in the ring, has now re-accelerated to 3,600 km/s. Soon after the SN 1987A outburst, three major groups embarked in a photometric monitoring of the supernova: the South African Astronomical Observatory (SAAO), the Cerro Tololo Inter-American Observatory (CTIO), and

2622-544: The small fraction of the Co and Co gamma rays that escaped the SN1987A remnant without absorption confirmed earlier predictions that those two radioactive nuclei were the power source. Because the Co in SN1987A has now completely decayed, it no longer supports the luminosity of the SN 1987A ejecta. That is currently powered by the radioactive decay of Ti with a half life of about 60 years. With this change, X-rays produced by

2679-411: The star might have merged with a companion star before the supernova. However, it is now widely understood that blue supergiants are natural progenitors of some supernovae, although there is still speculation that the evolution of such stars could require mass loss involving a binary companion. Approximately two to three hours before the visible light from SN 1987A reached Earth, a burst of neutrinos

2736-449: The supernova brightening rapidly early on February 23. On March 4–12, 1987, it was observed from space by Astron , the largest ultraviolet space telescope of that time. Four days after the event was recorded, the progenitor star was tentatively identified as Sanduleak −69 202 (Sk -69 202), a blue supergiant . After the supernova faded, that identification was definitively confirmed, as Sk −69 202 had disappeared. The possibility of

2793-443: The telescopes and film change and retrieval. It also carried additional life support systems including an Elektron oxygen generator and equipment for removing carbon dioxide from the air. Scientific equipment on board Kvant-1 included: To allow astronomical observations, Kvant-1 carried – in addition to two Earth horizon sensors, two star sensors, and three star trackers – six gyrodines which permitted extremely accurate pointing of

2850-645: Was attached to Kvant-1 was disposed of and the all-Russian solar array, which was also delivered with the Docking Module, was attached in its place. On February 23, 1997, a backup solid-fuel oxygen canister caught fire in the Kvant-1 module. The fire spewed molten metal, and the crew was concerned that it could melt through the hull of the space station. Smoke filled the station, and the crew donned respirators to continue breathing, although some respirators were faulty and did not supply oxygen. After burning for fourteen minutes and using up three fire extinguishers,

2907-609: Was designed to test girder assembly experiments for a possible Mir 2 space station. External experiments were also later held on the Rapana girder. In June, 1996, the Rapana girder was extended during an EVA. On May 22, 1995, one of Kristall 's solar panels was redeployed on Kvant-1. In May 1996, the Mir Cooperative Solar Array, which was delivered with the Mir Docking Module , was deployed on Kvant-1. In November 1997, Kristall's old solar panel that

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2964-695: Was discovered using the Atacama Large Millimeter Array telescope. Further evidence was subsequently uncovered in 2021 through observations conducted by the Chandra and NuSTAR X-ray telescopes. SN 1987A was discovered independently by Ian Shelton and Oscar Duhalde at the Las Campanas Observatory in Chile on February 24, 1987, and within the same 24 hours by Albert Jones in New Zealand . Later investigations found photographs showing

3021-537: Was mated with a Functional Service Module (FSM) – carrying propulsion and electrical systems – to act as a space tug. The FSM was derived from the TKS spacecraft , which would later form the basis for the Functional Cargo Block of the Kvant-2 , Kristall , Spektr , and Priroda modules. Kvant-1 and its FSM were launched on March 30, 1987 – at the time of the launch, the Mir station was staffed by

3078-483: Was not equipped with its own propulsion system. The original authorisation was for a total of eight 37K's of various configurations: The 37KE was designated Kvant and was equipped with an astrophysics payload. It also used the Salyut-5B digital flight control computer and Gyrodyne flywheel orientation system developed for Almaz . As the module neared completion Salyut 7 experienced numerous technical problems and Kvant

3135-501: Was observed at three neutrino observatories . This was likely due to neutrino emission which occurs simultaneously with core collapse, but before visible light is emitted as the shock wave reaches the stellar surface. At 7:35 UT , 12 antineutrinos were detected by Kamiokande II , 8 by IMB , and 5 by Baksan in a burst lasting less than 13 seconds. Approximately three hours earlier, the Mont Blanc liquid scintillator detected

3192-463: Was retargeted for docking with Mir. But at that time Mir was planned to be in a 65-degree orbit, and Kvant was 800 kg too heavy for the Proton launch vehicle to place in such an orbit. In January 1985 Mir was changed to a 51.6-degree orbit, which solved one problem. But now it was planned that Kvant would dock with the rear port of Mir, requiring the addition of lines to conduct rocket propellant from

3249-507: Was the closest observed supernova since Kepler's Supernova in 1604. Light and neutrinos from the explosion reached Earth on February 23, 1987 and was designated "SN 1987A" as the first supernova discovered that year. Its brightness peaked in May of that year, with an apparent magnitude of about 3. It was the first supernova that modern astronomers were able to study in great detail, and its observations have provided much insight into core-collapse supernovae . SN 1987A provided

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