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Long March 4C
The Long March 4C, also known as the Chang Zheng 4C, CZ-4C and LM-4C, previously designated Long March 4B-II, is a Chinese orbital launch vehicle. It is launched from the Jiuquan, Taiyuan, and Xichang Satellite Launch Centers, and consists of 3 stages. Long March 4C vehicles have been used to launch the Yaogan-1, Yaogan-3 synthetic-aperture radar (SAR) satellites and the Fengyun-3A polar orbiting meteorological satellite. On 15 December 2009, a Long March 4C was used to launch Yaogan-8. Because it was still designated as Long March 4B-II at the time of its maiden flight, the first launch is often mistaken for a Long March 4B. The Long March 4C is derived from the Long March 4B, but features a restartable upper stage, and a larger payload fairing. On 1 September 2016, the Long March 4C failed for reasons not yet known. A Long March 4C rocket blasted off from the Taiyuan Satellite Launch Center in Shanxi but failed to insert its payload, the Gaofen 10 satellite, into its d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Launch Vehicle
A launch vehicle is typically a rocket-powered vehicle designed to carry a payload (a crewed spacecraft or satellites) from Earth's surface or lower atmosphere to outer space. The most common form is the ballistic missile-shaped multistage rocket, but the term is more general and also encompasses vehicles like the Space Shuttle. Most launch vehicles operate from a launch pad, supported by a missile launch control center, launch control center and systems such as vehicle assembly and fueling. Launch vehicles are engineered with advanced aerodynamics and technologies, which contribute to high operating costs. An orbital spaceflight, 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 spaceflight, Suborbital vehicles launch their payloads to lower velocity or are launched at elevation angles greater than horizontal. Practical orbital launch vehicles use chemical prope ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
YF-40
The YF-40 is a Chinese liquid rocket engine burning N2O4 and UDMH in a gas generator cycle. It has dual gimbaling combustion chambers. Originally it was developed for the Long March 1D The Long March 1D was a member of China's Long March rocket family. During the 1990s China Academy of Launch Vehicle Technology, CALT developed an improved version of the DF-4 to test the Atmospheric entry, reentry vehicle warheads of the DF-31. ... second stage. It is used on the third stage of the Long March 4 family of launch vehicles. References Rocket engines of China Rocket engines using hypergolic propellant Rocket engines using the gas-generator cycle {{rocket-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sun-synchronous Orbit
A Sun-synchronous orbit (SSO), also called a heliosynchronous orbit, is a nearly polar orbit around a planet, in which the satellite passes over any given point of the planet's surface at the same local mean solar time. More technically, it is an orbit arranged so that it Precession, precesses through one complete revolution each year, so it always maintains the same relationship with the Sun. Applications A Sun-synchronous orbit is useful for imaging satellite, imaging, reconnaissance satellite, reconnaissance, and weather satellites, because every time that the satellite is overhead, the surface illumination angle on the planet underneath it is nearly the same. This consistent lighting is a useful characteristic for satellites that image the Earth's surface in visible or infrared wavelengths, such as weather and spy satellites, and for other remote-sensing satellites, such as those carrying ocean and atmospheric remote-sensing instruments that require sunlight. For example, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coordinated Universal Time
Coordinated Universal Time (UTC) is the primary time standard globally used to regulate clocks and time. It establishes a reference for the current time, forming the basis for civil time and time zones. UTC facilitates international communication, navigation, scientific research, and commerce. UTC has been widely embraced by most countries and is the effective successor to Greenwich Mean Time (GMT) in everyday usage and common applications. In specialised domains such as scientific research, navigation, and timekeeping, other standards such as Universal Time, UT1 and International Atomic Time (TAI) are also used alongside UTC. UTC is based on TAI (International Atomic Time, abbreviated from its French name, ''temps atomique international''), which is a weighted average of hundreds of atomic clocks worldwide. UTC is within about one second of mean solar time at 0° longitude, the currently used prime meridian, and is not adjusted for daylight saving time. The coordination of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gaofen (satellite)
Gaofen () is a series of Chinese high-resolution Earth imaging satellites launched as part of the China High-resolution Earth Observation System (CHEOS) program. CHEOS is a state-sponsored, civilian Earth-observation program used for agricultural, disaster, resource, and environmental monitoring. Proposed in 2006 and approved in 2010, the CHEOS program consists of the Gaofen series of space-based satellites, near-space and airborne systems such as airships and UAVs, ground systems that conduct data receipt, processing, calibration, and taskings, and a system of applications that fuse observation data with other sources to produce usable information and knowledge. Although the first seven Gaofen satellites and their payloads have been heavily detailed, little to no details on Gaofen 8 and later satellites have been revealed prompting suggestions that Gaofen satellites may be dual purpose supporting both civilian and military missions. In 2003, the China National Space Admini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shanxi
Shanxi; Chinese postal romanization, formerly romanised as Shansi is a Provinces of China, province in North China. Its capital and largest city of the province is Taiyuan, while its next most populated prefecture-level cities are Changzhi and Datong. Its one-character abbreviation is (), after the Jin (Chinese state), state of Jin that existed there during the Spring and Autumn period (). The name ''Shanxi'' means 'west of the mountains', a reference to its location west of the Taihang Mountains. Shanxi borders Hebei to the east, Henan to the south, Shaanxi to the west and Inner Mongolia to the north. Shanxi's terrain is characterised by a plateau bounded partly by mountain ranges. Shanxi's culture is largely dominated by the ethnic Han Chinese, Han majority, who make up over 99% of its population. Jin Chinese is considered by some linguists to be a distinct language from Mandarin and its geographical range covers most of Shanxi. Both Jin and Mandarin are spoken in Shanxi. ... [...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 velocity and height. In serial or tandem staging schemes, the first stage is at the bottom and is usually the largest, the second stage and subse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Long March 4B
The Long March 4B (), also known as the Chang Zheng 4B, CZ-4B, and LM-4B, is a Chinese expendable orbit, orbital launch vehicle. Launched from Launch Complex 1 at the Taiyuan Satellite Launch Center, it is a 3-stage launch vehicle, used mostly to place satellites into low Earth orbit and Sun-synchronous orbits. It was first launched on 10 May 1999, with the FY-1C weather satellite, which would later be the target in the 2007 Chinese anti-satellite missile test. The Chang Zheng 4B experienced its only launch failure on 9 December 2013, with the loss of the CBERS-3 satellite. Launch statistics Number of launches, by year. List of launches See also * Long March 4C * Long March (rocket family) * Medium-lift launch vehicle References {{Long March rockets Long March (rocket family) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weather Satellite
A weather satellite or meteorological satellite is a type of Earth observation satellite that is primarily used to monitor the weather and climate of the Earth. Satellites are mainly of two types: polar orbiting (covering the entire Earth asynchronously) or geostationary (hovering over the same spot on the equator). While primarily used to detect the development and movement of storm systems and other cloud patterns, meteorological satellites can also detect other phenomena such as city lights, fires, effects of pollution, auroras, sand and dust storms, snow cover, ice mapping, boundaries of ocean currents, and energy flows. Other types of environmental information are collected using weather satellites. Weather satellite images helped in monitoring the volcanic ash cloud from Mount St. Helens and activity from other volcanoes such as Mount Etna. Smoke from fires in the western United States such as Colorado and Utah have also been monitored. El Niño and its effects on wea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fengyun
Fēngyún (FY, ) are China's meteorological satellites. Launched since 1988 into polar Sun-synchronous and geosynchronous orbit, each three-axis stabilized Fengyun satellite is built by the Shanghai Academy of Spaceflight Technology ( SAST) and operated by the China Meteorological Administration ( CMA). To date, China has launched twenty-one Fengyun satellites in four classes (FY-1 through FY-4). Fengyun 1 and Fengyun 3 satellites are in polar, Sun-synchronous orbit and Low Earth orbit while Fengyun 2 and 4 are geosynchronous orbit. On 11 January 2007, China destroyed one of these satellites (FY-1C, COSPAR 1999-025A) in a test of an anti-satellite missile. According to NASA, the intentional destruction of FY-1C created more than 3,000 high-velocity debris items, a larger amount of dangerous space debris than any other space mission in history. Classes Fengyun 1 The four satellites of the Fengyun 1 (or FY-1) class were China's first meteorological satellites placed in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synthetic-aperture Radar
Synthetic-aperture radar (SAR) is a form of radar that is used to create two-dimensional images or three-dimensional reconstructions of objects, such as landscapes. SAR uses the motion of the radar antenna over a target region to provide finer spatial resolution than conventional stationary beam-scanning radars. SAR is typically mounted on a moving platform, such as an aircraft or spacecraft, and has its origins in an advanced form of side looking airborne radar (SLAR). The distance the SAR device travels over a target during the period when the target scene is illuminated creates the large ''synthetic'' antenna aperture (the ''size'' of the antenna). Typically, the larger the aperture, the higher the image resolution will be, regardless of whether the aperture is physical (a large antenna) or synthetic (a moving antenna) – this allows SAR to create high-resolution images with comparatively small physical antennas. For a fixed antenna size and orientation, objects which are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
