 Spektr-R at the integration and test complex of Launch Pad No.31, the Baikonur Space Center in July 2011 | |
| Names | RadioAstron |
|---|---|
| Mission type | Radio telescope |
| Operator | Russian Astro Space Center |
| COSPAR ID | 2011-037A |
| SATCATno. | 37755 |
| Website | http://www.asc.rssi.ru/radioastron/ |
| Mission duration | Planned: 5 years Achieved: 7 years, 10 months, 11 days |
| Spacecraft properties | |
| Bus | Navigator[1] |
| Manufacturer | NPO Lavochkin |
| Launch mass | 3,660 kg (8,069 lb)[1] |
| Payload mass | 2,500 kg (5,512 lb)[1] |
| Start of mission | |
| Launch date | 18 July 2011, 02:31 (2011-07-18UTC02:31) UTC[2] |
| Rocket | Zenit-3F[3][4] |
| Launch site | Baikonur Cosmodrome Pad 45/1[2] |
| Contractor | Roscosmos |
| End of mission | |
| Disposal | Equipment failure |
| Declared | 30 May 2019 |
| Last contact | 11 January 2019 |
| Orbital parameters | |
| Reference system | Geocentric |
| Regime | Highly elliptical |
| Semi-major axis | 180,974.7 km (112,452 mi) |
| Eccentricity | 0.905900 |
| Perigee altitude | 10,651.6 km (6,619 mi) |
| Apogee altitude | 338,541.5 km (210,360 mi) |
| Inclination | 42.46° |
| Period | 12769.93 min |
| RAAN | 67.28° |
| Argument of perigee | 244.85° |
| Mean anomaly | 3.07° |
| Mean motion | 0.1126 rev/day |
| Epoch | 24 February 2016, 23:21:29 UTC[5] |
| Revolutionno. | 197 |
| Main telescope | |
| Diameter | 10 m (33 ft)[1] |
| Focal length | 4.22 m (13.8 ft)[1] |
| Wavelengths | 92, 18, 6, 1.3 cm[1] |
Spektr program | |
Spektr-R[6] (part of RadioAstron program) (Russian: Спектр-Р) was a Russian scientific satellite with a 10 m (33 ft)radio telescope on board. It was launched on 18 July 2011[7] on aZenit-3F launcher fromBaikonur Cosmodrome, and was designed to perform research on the structure and dynamics ofradio sources within and beyond theMilky Way. Together with some of the largest ground-based radio telescopes, the Spektr-R formedinterferometric baselines extending up to 350,000 km (220,000 mi).
On 11 January 2019, the spacecraft stopped responding to ground control, but its science payload was described as "operational". The mission never recovered from the January 2019 incident, and the mission was declared finished (and spacecraft operations ended) on 30 May 2019.
The Spektr-R project was funded by theAstro Space Center of Russia, and was launched intoEarth orbit on 18 July 2011,[3] with aperigee of 10,000 km (6,200 mi) and anapogee of 390,000 km (240,000 mi), about 700 times the orbital height of theHubble Space Telescope at its highest point and 20 times at its lowest.[8][9] In comparison, the average distance from Earth to the Moon is 384,400 km (238,900 mi).[10] As of 2018, the satellite has a much more stable orbit with a perigee of 57,000 km (35,000 mi) and an apogee of 320,000 km (200,000 mi), with its orbit no longer intersecting the Moon's orbit and being stable for possibly hundreds or even thousands of years.
The main scientific goal of the mission was the study of astronomical objects with anangular resolution up to a few millionths of anarcsecond. This was accomplished by using the satellite in conjunction with ground-based observatories andinterferometry techniques.[3] Another purpose of the project was to develop an understanding of fundamental issues ofastrophysics andcosmology. This includedstar formations, the structure ofgalaxies,interstellar space,black holes anddark matter.
Spektr-R was one of the instruments in theRadioAstron program, an international network of observatories led by theAstro Space Center of theLebedev Physical Institute.[8]
The telescope was intended for radio-astrophysical observations of extragalactic objects with ultra-high resolution, as well as researching of characteristics of near-Earth and interplanetary plasma. The very highangular resolving power was achieved in conjunction with a ground-based system of radio-telescopes andinterferometrical methods, operating atwavelengths of 1.35–6.0, 18.0 and 92.0 cm.[11] Once in space, the flower-like main dish was to open its 27 'petals' within 30 minutes.[citation needed]
There was a science payload of opportunity on board, PLASMA-F, which consists of four instruments to observe solar wind and the outer magnetosphere. These instruments are the energetic particle spectrometer MEP-2, the magnetometer MMFF, the solar wind monitor BMSW, and the data collection and processing unit SSNI-2.[12]
At launch the mass of the spacecraft was 3,660 kg (8,070 lb). It was launched from theBaikonur Cosmodrome on 18 July 2011 at 02:31 UTC by aZenit-3F launch vehicle, which is composed of aZenit-2M with aFregat-SB upper stage.[3][4]
On 11 January 2019, the spacecraft stopped responding to ground control. It was unknown whether the issue could be fixed, or whether the spacecraft's mission would be ended.[13] With Spektr-R's status unknown and the problems hitting theMikhailo Lomonosov satellite, the Russian space program had no operational space observatories as of 12 January 2019. This changed with the launch of theSpektr-RG satellite in July 2019.
The mission was declared as finished on 30 May 2019.[14]
The external tank of the Fregat upper stage that delivered the Spektr-R observatory into orbit exploded on May 8, 2020, generating at least 65 trackable debris in orbit around Earth.[15]
At the beginning of the 1980s, one of theUSSR's leading developers of scientific space probes had completed a preliminary design of revolutionary, new-generation spacecraft, 1F and 2F. The main purpose of Spektr was to develop a common platform that could be used for future deep-space missions.
NPO Lavochkin hoped to use the designs of the 1F as the standard design forspace telescopes. In 1982,NPO Lavochkin had completed technical blueprints for RadioAstron, a space-basedradio telescope. The expectation was that the 1F and 2F spacecraft would follow the expectations of the RadioAstron mission (also known as Astron-2).
Early on, many criticized the 1F platform for its questionableastrophysics missions, even when compared to the older 4Vspacecraft bus. Although theattitude control system of the 1F seemed to have little issues navigating planetary probes, its accuracy was much below the standard requirements for a high-precisiontelescope. To add to 1F's technical issues, thespacecraft seemed to lack electrically driven fly-wheels, which critics believed would have increased its stabilization in space. Thespacecraft also failed to have a moveable solar panel system, which could track the position of theSun without requiring the entiresatellite to reposition, eventually disrupting the observations process.
It was one of three competing Spectrum missions, the others being Spektr X-Gammaand Spektr-UV[16]
On 1 August 1983, VPK, theSoviet Military Industrial Commission commissioned an official decision (number 274) titled, "On works for creation of automated interplanetary vehicles for the exploration of planets of theSolar System, theMoon andcosmic space". This document outlined a new impetus for the development ofsatellites. The new technical proposals submitted in mid-1984 included agamma-ray telescope designated to registerradio waves in the millimetre range. Both of these satellites incorporated rotatingsolar panels, a highly sensitive star-tracking operating system and fly wheels.
By the end of the 1980s, NPO Lavochkin Designer General, Vyacheslav Kovtunenko(ru), proposed to design all future astrophysics satellites on the currentOko-1 spacecraft model, designed originally to track incoming ballistic missiles. According to this plan, Oko-1 (a missile-watchinginfrared telescope) would eventually be replaced with scientific instruments where thesatellite would be pointed towardsspace rather thanEarth.
 | This sectiondoes notcite anysources. Please helpimprove this section byadding citations to reliable sources. Unsourced material may be challenged andremoved.(October 2014) (Learn how and when to remove this message) |
Using a technique calledvery-long-baseline interferometry, it was anticipated that ground telescopes in Australia,Chile, China, India, Japan,Korea,Mexico, Russia,South Africa,Ukraine and the United States would jointly make observations with the RadioAstron spacecraft.
The RadioAstron satellite's main 10-metreradio telescope would communicate in four different bands of radio waves with the international ground telescopes. It can also locate sources from two frequencies simultaneously.[17] The Spektr-R was also planned to include a secondary BMSV within the Plazma-F experiment, the goal of which was to measure the directions and intensity of solar wind. In May 2011, the news agencyRIA Novosti reported that the BMSV instrument would indeed be on board. It was also reported that the BMSV would carry amicrometeoroid counter made in Germany.
The RadioAstron was expected to extend into a highlyelliptical orbit in theFregat state of theZenit rocket's launch. Spektr-R's closest point (perigee) would be 500 kilometres (310 mi) above theEarth's surface, with itsapogee 340,000 kilometres (210,000 mi) away. The operationalorbit would last at least nine years, with the RadioAstron never being in the Earth's shadow for more than two hours.
With its apogee as far as the orbit of theMoon, Spektr-R could be considered a deep-space mission. In fact, the gravitational pull of the Moon was expected to fluctuate the satellite's orbit in three-year cycles, with its apogee travelling between 265,000 and 360,000 kilometres (220,000 mi) from Earth and its perigee between 400 and 65,000 kilometres (250 and 40,390 mi). Each orbit would take RadioAstron around eight to nine days. This drift would vastly augment the telescope's range of vision. It was estimated that the satellite would have upwards of 80% of its potential targets within view at any one point in its orbit. The first 45 days of Spektr-R's orbit were scheduled to consist of engineering commissioning, that is, the launch of the mainantenna, various systems checks and communications tests.
Spektr-R's tracking was to be handled by theRT-22 radio telescope inPushchino, Russia. Flight control would be operated by ground stations inMedvezhi Ozera [ru] nearMoscow andUssuriysk in Russia's Far East. Other Spektr-R joint observations would be handled by ground telescopes in Arecibo, Badary, Effelsberg, Green Bank, Medicina, Noto, Svetloe, Zelenchukskaya and Westerbork.
The Spektr-R project was led by theRussian Academy of Sciences'sAstro Space Center of theLebedev Physics Institute. The radio receivers on Spektr-R were to be built in India and Australia. In earlier plans, two additional receivers were to be provided by firms under contract with the EuropeanVLBI Consortium, theEVN. These additional payloads were eventually cancelled, with the project citing old age. Similar Russian materials replaced the Indian and Australian instruments.
| Operating |
| ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Planned | |||||||||||||
| Proposed | |||||||||||||
| Retired |
| ||||||||||||
| Hibernating (Mission completed) | |||||||||||||
| Lost/Failed | |||||||||||||
| Cancelled | |||||||||||||
| Related |
| ||||||||||||
| Launch sites |  | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Launch vehicles | |||||||||
| Human spaceflight programs |
| ||||||||
| Robotic programs |
| ||||||||
| Communications | |||||||||
| Concepts | |||||||||
| Images and artwork | |||||||||
| Related | |||||||||
