Fregat-M
Fregat () is an upper stage developed by NPO Lavochkin for universal compatibility with a wide range of medium- and heavy-lift launch vehicles. Fregat has been used primarily with Soyuz and Zenit rockets, and entered operational service in February 2000. Fregat uses a liquid-propellant engine burning unsymmetrical dimethylhydrazine (UDMH) fuel and dinitrogen tetroxide () oxidizer, a pair of hypergolic propellants that ignite on contact. With a success rate of 97.3%, including two failures and one partial failure, Fregat is among the most reliable upper stages in operation. It has deployed more than 300 payloads into a variety of orbits and is capable of placing three or more spacecraft into distinct orbits during a single mission, owing to its ability to restart up to seven times and operate for a total burn duration of up to 1,350 seconds. Description The Fregat upper stage is a versatile and autonomous vehicle designed to inject large payloads into a range of orbits, inc ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Soyuz-ST
The Soyuz-ST-A and ST-B were modified versions of the Soyuz-2 rocket, designed to launch from the Guiana Space Centre (CSG) in French Guiana. Developed as part of a European Space Agency (ESA) programme to add a medium-lift launch vehicle to complement the light-lift Vega and heavy-lift Ariane 5 rockets. A collaborative effort between Russia and Europe, the project involved constructing the Ensemble de Lancement Soyouz (ELS; ) at the CSG and adapting the Soyuz 2 to the tropical climate. The first launch of a Soyuz ST-B occurred on 21 October 2011, while the first ST-A launch occurred on 17 December 2011. The Soyuz-ST-A and ST-B were four-stage rockets designed for low Earth orbit missions. Notably, their stage numbering differs from that of some rockets, with the boosters considered the first stage and the central core the second. Unlike the standard Soyuz-2, the Fregat upper stage was mandatory for the ST variants. Between 2011 and 2022, 27 Soyuz-ST rockets were launched f ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Meridian (satellite)
Meridian (Russian: Меридиан) is a family of telecommunications satellites for civil and military use developed by Russia in the 2000s, placed in a Molniya Orbit, and intended to replace the two last series of Molniya satellites still in activity, as well as the old Parus satellites. The first launch took place on 24 December 2006, aboard a Soyuz 2.1a. Seven satellites were launched between 2006 and 2014, six of which reached orbit. A second generation of satellite, Meridian-M, was ordered, and the first unit was launched on 30 July 2019. Technical characteristics This family of satellites was developed in the mid-2000s by the main Russian satellite manufacturer, ISS Reshetnev, who had already built the Molniya satellites. According to unofficial sources, the satellite uses 3 axes stabilized pressurized platform. Certain components, like the on-board computer and the propulsion, would be common with the Uragan-M satellites of the Glonass satellite navigation system. The ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Soyuz-2
Soyuz2 (; GRAU index: 14A14) is a Russian expendable medium-lift launch vehicle and the seventh major iteration of the Soyuz rocket family. Compared to its predecessors, Soyuz-2 features significant upgrades, including improved engines and a digital flight control system that enables launches from fixed platforms and supports larger payload fairings. Developed by the Progress Rocket Space Centre (RKTs Progress) in Samara, Soyuz-2 is used to place payloads into low Earth orbit in standard configuration but can also support missions to higher orbits using an additional upper stage, most commonly the Fregat, though the smaller Volga is available as a less expensive option. Since its introduction in 2004, Soyuz-2 has gradually replaced earlier Soyuz variants and is launched from the facilities of its R-7 derived predecessors: Site 31/6 at the Baikonur Cosmodrome in Kazakhstan and Sites 43/3 and 43/4 at the Plesetsk Cosmodrome in northwestern Russia, and, since 2016, Site ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Upper Stage
A multistage rocket or step rocket is a launch vehicle that uses two or more rocket ''stages'', each of which contains its own Rocket engine, engines and Rocket propellant, propellant. A ''tandem'' or ''serial'' stage is mounted on top of another stage; a ''parallel'' stage is attached alongside another stage. The result is effectively two or more rockets stacked on top of or attached next to each other. Two-stage rockets are quite common, but rockets with as many as five separate stages have been successfully launched. By jettisoning stages when they run out of propellant, the mass of the remaining rocket is decreased. Each successive stage can also be optimized for its specific operating conditions, such as decreased atmospheric pressure at higher altitudes. This ''staging'' allows the thrust of the remaining stages to Newton's First Law of Motion, more easily accelerate the rocket to its final velocity and height. In serial or tandem staging schemes, the first stage is at th ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Mars Express
''Mars Express'' is a space exploration mission by the European Space Agency, European Space Agency (ESA) exploring the planet Mars and its moons since 2003, and the first planetary mission attempted by ESA. ''Mars Express'' consisted of two parts, the ''Mars Express Orbiter'' and ''Beagle 2'', a Lander (spacecraft), lander designed to perform exobiology and geochemistry research. Although the lander failed to fully deploy after it landed on the Martian surface, the orbiter has been successfully performing scientific measurements since early 2004, namely, image resolution, high-resolution imaging and mineralogical mapping of the surface, radar sounding of the subsurface structure down to the permafrost, precise determination of the atmospheric circulation and composition, and study of the interaction of the Atmosphere of Mars, atmosphere with the interplanetary medium. Due to the valuable science return and the highly flexible mission profile, ''Mars Express'' has been granted ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Low Earth Orbit
A low Earth orbit (LEO) is an geocentric orbit, orbit around Earth with a orbital period, period of 128 minutes or less (making at least 11.25 orbits per day) and an orbital eccentricity, eccentricity less than 0.25. Most of the artificial objects in outer space are in LEO, peaking in number at an altitude around , while the farthest in LEO, before medium Earth orbit (MEO), have an altitude of 2,000 km, about one-third of the Earth radius, radius of Earth and near the beginning of the Van Allen radiation belt#Inner belt, inner Van Allen radiation belt. The term ''LEO region'' is used for the area of space below an altitude of (about one-third of Earth's radius). Objects in orbits that pass through this zone, even if they have an apogee further out or are sub-orbital spaceflight, sub-orbital, are carefully tracked since they present a collision risk to the many LEO satellites. No human spaceflights other than the lunar missions of the Apollo program (1968-1972) have gone beyond L ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Medium Earth Orbit
A medium Earth orbit (MEO) is an geocentric orbit, Earth-centered orbit with an altitude above a low Earth orbit (LEO) and below a high Earth orbit (HEO) – between above sea level.''Catalog of Earth Satellite Orbits'' NASA Earth Observatory. 4 September 2009. Accessed 2 May 2021. The boundary between MEO and LEO is an arbitrary altitude chosen by accepted convention, whereas the boundary between MEO and HEO is the particular altitude of a geosynchronous orbit, in which a satellite takes 24 hours to circle the Earth, the same period as the Earth’s own rotation. All satellites in MEO have an orbital period of less than 24 hours, with the minimum period (for a circular orbit at the lowest MEO altitude) about 2 hours. Satellites in MEO or ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Geosynchronous Orbit
A geosynchronous orbit (sometimes abbreviated GSO) is an Earth-centered orbit with an orbital period that matches Earth's rotation on its axis, 23 hours, 56 minutes, and 4 seconds (one sidereal day). The synchronization of rotation and orbital period means that, for an observer on Earth's surface, an object in geosynchronous orbit returns to exactly the same position in the sky after a period of one sidereal day. Over the course of a day, the object's position in the sky may remain still or trace out a path, typically in a figure-8 form, whose precise characteristics depend on the orbit's inclination and eccentricity. A circular geosynchronous orbit has a constant altitude of . A special case of geosynchronous orbit is the geostationary orbit (often abbreviated ''GEO''), which is a circular geosynchronous orbit in Earth's equatorial plane with both inclination and eccentricity equal to 0. A satellite in a geostationary orbit remains in the same position in the sky to observers ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Venus Express
''Venus Express'' (VEX) was the first Venus exploration mission of the European Space Agency (ESA). Launched in November 2005, it arrived at Venus in April 2006 and began continuously sending back science data from its polar orbit around Venus. Equipped with seven scientific instruments, the main objective of the mission was the long term observation of the Venusian atmosphere. The observation over such long periods of time had never been done in previous missions to Venus, and was key to a better understanding of the atmospheric dynamics. ESA concluded the mission in December 2014. History The mission was proposed in 2001 to reuse the design of the ''Mars Express'' mission. However, some mission characteristics led to design changes: primarily in the areas of thermal control, communications and electrical power. For example, since Mars is approximately twice as far from the Sun as Venus, the radiant heating of the spacecraft is four times greater for ''Venus Express'' than '' ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Satellite Bus
A satellite bus (or spacecraft bus) is the main body and structural component of a satellite or spacecraft, in which the payload and all scientific instruments are held. Bus-derived satellites are less customized than specially-produced satellites, but have specific equipment added to meet customer requirements, for example with specialized sensors or transponders, in order to achieve a specific mission. They are commonly used for geosynchronous satellites, particularly communications satellites, but are most commonly used in spacecraft which occupy low Earth orbit missions. Examples Some satellite bus examples include: * Boeing DS&S 702 * Lockheed Martin Space Systems A2100 * Moog Inc. SL-OMV, Meteor, Meteorite * * INVAP ARSAT-3K * Airbus D&S Eurostar * ISRO's I-1K, I-2K, I-3K, I-4K, I-6K, and Indian Mini Satellite bus * NASA Ames MCSB * SSL 1300 * family * Orbital ATK Star Bus family, inc GEOStar * Mitsubishi Electric DS2000 * Spacecraft bus of the Jam ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Starsem
Starsem is a French-Russian company that was created in 1996 to commercialise the Soyuz launcher internationally. Starsem is headquartered in Évry, France (near Paris) and has the following shareholders: * ArianeGroup (35%) * Arianespace (15%) * Roscosmos (25%) * Progress Rocket Space Centre Rocket and Space Centre "Progress" (), commonly known as RKTs Progress (), is a Russian joint-stock company under Roscosmos. It is responsible for building and operating the Soyuz (rocket family), Soyuz family of rockets, which serve as the pri ... (25%) References External links Starsem, the Soyuz company website Commercial launch service providers Space industry companies of Russia {{rocket-stub ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Dinitrogen Tetroxide
Dinitrogen tetroxide, commonly referred to as nitrogen tetroxide (NTO), and occasionally (usually among ex-USSR/Russian rocket engineers) as amyl, is the chemical compound N2O4. It is a useful reagent in chemical synthesis. It forms an equilibrium mixture with nitrogen dioxide. Its molar mass is 92.011 g/mol. Dinitrogen tetroxide is a powerful oxidizer that is hypergolic (spontaneously reacts) upon contact with various forms of hydrazine, which has made the pair a common bipropellant for rockets. Structure and properties Dinitrogen tetroxide could be regarded as two nitro groups (-NO2) bonded together. It forms an equilibrium mixture with nitrogen dioxide. The molecule is planar with an N-N bond distance of 1.78Å and N-O distances of 1.19Å. The N-N distance corresponds to a weak bond, since it is significantly longer than the average N-N single bond length of 1.45Å. This exceptionally weak σ bond (amounting to overlapping of the ''sp''2 hybrid orbitals of the two NO2 uni ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |