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Ekspress-MD2
Ekspress-MD2 is a Russian communications satellite which was lost due to a launch failure on 6 August 2012. Equipped with eight C-band transponders and 1 L-band transponder, it was intended to be located in geostationary orbit at a longitude of 145° East. It was the second Ekspress-MD satellite to be launched, following Ekspress-MD1 in 2009. Launch Ekspress-MD2 was launched atop a Proton-M launch vehicle with a Briz-M upper stage on 6 August 2012 at 19:31:00 UTC. The Indonesian Telkom-3 satellite was also carried aboard the launch vehicle. Launch occurred from Site 81/24 at the Baikonur Cosmodrome in Kazakhstan. The first three stages of the Proton launched worked as expected and the satellites were attached to the Briz-M upper stage which would transfer them into geosynchronous orbit. The Briz-M undertakes a series of four burns with coasting stages in order to do this. The third burn was due to be 18 minutes long but the engines cut out after 7 seconds, leaving the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telkom-3
Telkom-3 is an Indonesian communications satellite which failed to reach its target orbit due to a launch failure on 6 August 2012. It was built by ISS Reshetnev for Indonesian telecommunications provider PT Telekomunikasi Indonesia. It was based on the Ekspress-1000H bus and had 32 C band transponders and 16 Ku-band transponders. It was due to be located in geosynchronous orbit at 118° East above the equator. The satellite reentered the atmosphere and was destroyed on 5 February 2021. Launch Telkom-3 was launched along with Ekspress-MD2 by a Proton-M rocket with Briz-M upper stage on 6 August 2012 at 19:31:00 UTC. The satellites were launched from Site 81/24 at Baikonur Cosmodrome in Kazakhstan. The first three stages of the Proton launched worked as expected and the satellites were attached to the Briz-M upper stage which would transfer them into geosynchronous orbit. The Briz-M undertakes a series of four burns with coasting stages to do this. The third burn wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ekspress-MD1
Ekspress-MD1 (Russian: ), was a Russian geostationary communications satellite operated by Russian Satellite Communications Company (RSCC) and designed and manufactured by Khrunichev State Research and Production Space Center on the Yakhta satellite bus for RSCC's Ekspress series. It massed at launch, had a power production capacity of 1300 watts with a C-band and L-band payload. It was successfully launched along Ekspress-AM4 aboard a Proton-M / Briz-M from Baikonur on 11 February 2009. It was commissioned in the 80° East orbital position. The satellite failed on 4 July 2013, well short of its design life, for which RSCC collected the insurance. Satellite description Ekspress-MD1 was a geostationary communications satellite developed by Khrunichev State Research and Production Space Center on the Yakhta setellite bus. It is a small, three axis stabilized, satellite bus designed for direct geostationary orbit and as such it lacked an apogee kick motor. It was design ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Briz (rocket Stage)
The Briz-K, Briz-KM and Briz-M (russian: Бриз-К, КM and M meaning ''Breeze-K, KM and M'') are Russian liquid-propellant rocket orbit insertion upper stages manufactured by Khrunichev State Research and Production Space Center and used on the Proton-M and Angara A5. The upper stages were also used on Rokot, one of Russia's smaller launchers, before its retirement in 2019. Characteristics Briz-K and Briz-KM Briz-K, GRAU index 14S12, is a single-piece structure with a conical tank compartment and the engine located in a recess in the fuel tank. Briz-KM ( GRAU index 14S45) is an improved version of Briz-K. The Briz-K and Briz-KM were used as a third stage of the Rokot launch vehicles. Briz-M Briz-M, GRAU index 14S43, is designed for injecting large payloads into a low, medium-height or high geosynchronous orbit. Briz-M is a twin upper stage consisting of a core module (using Briz-KM as the baseline) and a jettisonable add-on toroidal tank surrounding the core. It ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proton-M
The Proton-M, (Протон-М) GRAU index 8K82M or , is an expendable Russian heavy-lift launch vehicle derived from the Soviet-developed Proton. It is built by Khrunichev, and launched from sites 81 and 200 at the Baikonur Cosmodrome in Kazakhstan. Commercial launches are marketed by International Launch Services (ILS), and generally use Site 200/39. The first Proton-M launch occurred on 7 April 2001. Proton flew its most recent mission on 13 December 2021, launching two Ekspress communication satellites into geostationary orbit. As of August 2020, a number of Roscosmos and other Russian government missions remain on Proton launch manifest. Vehicle description The Proton-M launch vehicle consists of three stages; all of them powered by liquid rocket engines using the hypergolic propellant combination of dinitrogen tetroxide as the oxidizer, and unsymmetrical dimethylhydrazine for fuel. The first stage is unique in that it consists of a central cylindrical oxidizer t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ekspress-AM4
Ekspress-AM4 was a Russian communications satellite placed into the wrong orbit from a faulty Briz-M rocket stage. This satellite was to be part of the Ekspress series of geostationary communications satellites owned by Russian Satellite Communications Company (RSCC). Proposals were made to reposition the satellite to provide broadband services to Antarctica, but ultimately the decision was made to de-orbit the satellite. On 28 March 2012, the satellite splashed into the Pacific Ocean. Satellite description The total mass of the Ekspress-AM4 satellite was , and the satellite had 63 transponders. The onboard antennas were capable of broadcasting in the C-band, Ku-band, L-band, and Ka-band. The satellite's orbit was measured at 695 by 20239 km altitude, with an inclination orbit of 51.1°. Though the satellite was placed in the wrong orbit, there was no damage to the satellite, meaning that it became the subject of numerous reuse proposals. Launch The Ekspress-AM4 sa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ekspress (satellite Constellation)
Ekspress (Russian: , ''literally'' Express) is a communication and broadcasting system developed and operated by Russian Satellite Communications Company (RSCC). It is the largest network of Russia and its slots cover an arc in geostationary orbit from 14.0° West to 145.0° East. This allows it to cover the whole territory of Russia, the CIS, Europe, the Middle East, Africa, the Asia-Pacific region, North and South America, and Australia. The only other Russian civilian satellite operator is Gazprom Space Systems with its Yamal constellation. Ekspress satellite series While the Ekspress constellation started with a single model, during the years it has used many suppliers and many models. See also * Telecommunications in Russia * Russian Satellite Communications Company – Satellite communication company of the Ministry of Telecom and Mass Communications of the Russian Federation and owner of the Ekspress satellite series. * Gazprom Space Systems – Satellite com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communications Satellite
A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. Communications satellites are used for television, telephone, radio, internet, and military applications. Many communications satellites are in geostationary orbit above the equator, so that the satellite appears stationary at the same point in the sky; therefore the satellite dish antennas of ground stations can be aimed permanently at that spot and do not have to move to track the satellite. Others form satellite constellations in low Earth orbit, where antennas on the ground have to follow the position of the satellites and switch between satellites frequently. The high frequency radio waves used for telecommunications links travel by line of sight and so are obstructed by the curve of the Earth. The purpose of communications ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C Band (IEEE)
The C band is a designation by the Institute of Electrical and Electronics Engineers (IEEE) for a portion of the electromagnetic spectrum in the microwave range of frequencies ranging from 4.0 to 8.0 gigahertz (GHz). However, the U.S. Federal Communications Commission C band proceeding and auction, designated 3.7–4.2 GHz as C band. The C band is used for many satellite communications transmissions, some Wi-Fi devices, some cordless telephones, as well as some Radar and weather radar systems. Use in satellite communication The communications C band was the first frequency band that was allocated for commercial telecommunications via satellites. The same frequencies were already in use for terrestrial microwave radio relay chains. Nearly all C-band communication satellites use the band of frequencies from 3.7 to 4.2 GHz for their downlinks, and the band of frequencies from 5.925 to 6.425 GHz for their uplinks. Note that by using the band fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multistage Rocket
A multistage rocket or step rocket is a launch vehicle that uses two or more rocket ''stages'', each of which contains its own engines and 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 more easily accelerate the rocket to its final speed and height. In serial or tandem staging schemes, the first stage is at the bottom and is usually the largest, the second stage and subseq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Launch Vehicle
A launch vehicle or carrier rocket is a rocket designed to carry a payload ( spacecraft or satellites) from the Earth's surface to outer space. Most launch vehicles operate from a launch pads, supported by a launch control center and systems such as vehicle assembly and fueling. Launch vehicles are engineered with advanced aerodynamics and technologies, which contribute to large operating costs. An orbital launch vehicle must lift its payload at least to the boundary of space, approximately and accelerate it to a horizontal velocity of at least . Suborbital vehicles launch their payloads to lower velocity or are launched at elevation angles greater than horizontal. Practical orbital launch vehicles are multistage rockets which use chemical propellants such as solid fuel, liquid hydrogen, kerosene, liquid oxygen, or Hypergolic propellants. Launch vehicles are classified by their orbital payload capacity, ranging from small-, medium-, heavy- to super-heavy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ground Track Ekspress Md2 Oct 12
Ground may refer to: Geology * Land, the surface of the Earth not covered by water * Soil, a mixture of clay, sand and organic matter present on the surface of the Earth Electricity * Ground (electricity), the reference point in an electrical circuit from which voltages are measured * Earthing system, part of an electrical installation that connects with the Earth's conductive surface * Ground and neutral, closely related terms Law * Ground (often grounds), in law, a rational motive or basis for a belief, conviction, or action taken, such as a legal action or argument: * Grounds for divorce, regulations specifying the circumstances under which a person will be granted a divorce Music * ''Ground'' (album), the second album by the Nels Cline Trio * "Ground" (song), one of the songs in the debut album of the Filipino rock band Rivermaya * Ground bass, in music, a bass part that continually repeats, while the melody and harmony over it change * ''The Ground'', a 2005 album by No ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geostationary Orbit
A geostationary orbit, also referred to as a geosynchronous equatorial orbit''Geostationary orbit'' and ''Geosynchronous (equatorial) orbit'' are used somewhat interchangeably in sources. (GEO), is a circular geosynchronous orbit in altitude above Earth's equator ( in radius from Earth's center) and following the direction of Earth's rotation. An object in such an orbit has an orbital period equal to Earth's rotational period, one sidereal day, and so to ground observers it appears motionless, in a fixed position in the sky. The concept of a geostationary orbit was popularised by the science fiction writer Arthur C. Clarke in the 1940s as a way to revolutionise telecommunications, and the first satellite to be placed in this kind of orbit was launched in 1963. Communications satellites are often placed in a geostationary orbit so that Earth-based satellite antennas do not have to rotate to track them but can be pointed permanently at the position in the sky where the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
