Spektr-R

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.

• Name — Spektr-R Спектр-Р • Names List — RadioAstron • Mission Type — Radio telescope • Operator — Russian Astro Space Center • Cospar Id — 2011-037A • Satcat — 37755 • Website — http: www.asc.rssi.ru/radioastron/ • Mission Duration — Planned: 5 years Achieved: 18 July 2011 02:31 • Spacecraft Bus — Navigator • Manufacturer — NPO Lavochkin • Launch Mass — 3660 kg • Payload Mass — 2500 kg • Launch Date — 18 July 2011, 02:31 UTC • Launch Rocket — Zenit-3F • Launch Site — Baikonur Cosmodrome Pad 45/1 • Launch Contractor — Roscosmos • Disposal Type — Equipment failure • Last Contact — 11 January 2019 • Declared — 30 May 2019 • Orbit Reference — Geocentric • Orbit Regime — Highly elliptical • Orbit Semimajor — 180974.7 km • Orbit Eccentricity — 0.905900 • Orbit Periapsis — 10651.6 km • Orbit Apoapsis — 338541.5 km • Orbit Inclination — 42.46° • Orbit Period — 12769.93 min • Orbit Raan — 67.28° • Orbit Arg Periapsis — 244.85° • Orbit Mean Anomaly — 3.07° • Orbit Mean Motion — 0.1126 rev/day • Orbit Epoch — 24 February 2016, 23:21:29 UTC • Orbit Rev Number — 197 • Apsis — gee • Telescope Diameter — 10 m • Telescope Focal Length — 4.22 m • Telescope Wavelength — 92, 18, 6, 1.3 cm • Programme — Spektr program • Next Mission — Spektr-RG

• Illustration — Model of Spektr-R The Spektr-R project was funded by the Astro Space Center of Russia, and was launched into Earth orbit on 18 July 2011, with a perigee of 10000 km and an apogee of 390000 km, about 700 times the orbital height of the Hubble Space Telescope at its highest point and 20 times at its lowest. In comparison, the average distance from Earth to the Moon is 384400 km. As of 2018, the satellite has a much more stable orbit with a perigee of 57000 km and an apogee of 320000 km, 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 an angular resolution up to a few millionths of an arcsecond. This was accomplished by using the satellite in conjunction with ground-based observatories and interferometry techniques. Another purpose of the project was to develop an understanding of fundamental issues of astrophysics and cosmology. This included star formations, the structure of galaxies, interstellar space, black holes and dark matter. Spektr-R was one of the instruments in the RadioAstron program, an international network of observatories led by the Astro Space Center of the Lebedev Physical Institute. 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 high angular resolving power was achieved in conjunction with a ground-based system of radio-telescopes and interferometrical methods, operating at wavelengths of 1.35–6.0, 18.0 and 92.0 cm. Once in space, the flower-like main dish was to open its 27 'petals' within 30 minutes. 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. At launch the mass of the spacecraft was 3660 kg. It was launched from the Baikonur Cosmodrome on 18 July 2011 at 02:31 UTC by a Zenit-3F launch vehicle, which is composed of a Zenit-2M with a Fregat-SB upper stage. 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. With Spektr-R's status unknown and the problems hitting the Mikhailo Lomonosov satellite, the Russian space program had no operational space observatories as of 12 January 2019. This changed with the launch of the Spektr-RG satellite in July 2019. The mission was declared as finished on 30 May 2019. 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.

At the beginning of the 1980s, one of the USSR 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 for space telescopes. In 1982, NPO Lavochkin had completed technical blueprints for RadioAstron, a space-based radio 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 questionable astrophysics missions, even when compared to the older 4V spacecraft bus. Although the attitude control system of the 1F seemed to have little issues navigating planetary probes, its accuracy was much below the standard requirements for a high-precision telescope. To add to 1F's technical issues, the spacecraft seemed to lack electrically driven fly-wheels, which critics believed would have increased its stabilization in space. The spacecraft also failed to have a moveable solar panel system, which could track the position of the Sun without requiring the entire satellite to reposition, eventually disrupting the observations process. It was one of three competing Spectrum missions, the others being Spektr X-Gamma and Spektr-UV On 1 August 1983, VPK, the Soviet Military Industrial Commission commissioned an official decision (number 274) titled, "On works for creation of automated interplanetary vehicles for the exploration of planets of the Solar System, the Moon and cosmic space". This document outlined a new impetus for the development of satellites. The new technical proposals submitted in mid-1984 included a gamma-ray telescope designated to register radio waves in the millimetre range. Both of these satellites incorporated rotating solar 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 current Oko-1 spacecraft model, designed originally to track incoming ballistic missiles. According to this plan, Oko-1 (a missile-watching infrared telescope) would eventually be replaced with scientific instruments where the satellite would be pointed towards space rather than Earth.