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IRS-1A
IRS-1A, Indian Remote Sensing satellite-1A, the first of the series of indigenous state-of-art remote sensing satellites, was successfully launched into a polar Sun-synchronous orbit on 17 March 1988 from the Soviet Cosmodrome at Baikonur. IRS-1A carries two sensors, LISS-1 and LISS-2, with resolutions of and respectively with a swath width of about during each pass over the country. Undertaken by the Indian Space Research Organisation (ISRO). It was a part-operational, part-experimental mission to develop Indian expertise in satellite imagery. History The availability of Landsat imagery created a lot of interest in the science community. The Hyderabad ground station started receiving Landsat data on a regular basis in 1978. The Landsat program with its design and potentials was certainly a great model and yardstick for the IRS programme. IRS-1A was the first remote sensing mission to provide imagery for various land-based applications, such as agriculture, forestry, geolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IRS-1B
IRS-1B, Indian Remote Sensing satellite-1B, the second of the series of indigenous state-of-art remote sensing satellites, was successfully launched into a polar Sun-synchronous orbit on 29 August 1991 from the Soviet Cosmodrome at Baikonur. IRS-1B carries two sensors, LISS-1 and LISS-2, with resolutions of and respectively with a swath width of about during each pass over the country. It was a part-operational, part-experimental mission to develop Indian expertise in satellite imagery. It was a successor to the remote sensing mission IRS-1A, both undertaken by the Indian Space Research Organisation (ISRO). History IRS-1B was the second remote sensing mission to provide imagery for various land-based applications, such as agriculture, forestry, geology, and hydrology. Satellite description Improved features compared to its predecessor (IRS-1A): gyroscope referencing for better orientation sensing, time tagged commanding facility for more flexibility in camera operation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indian Space Research Organization
The Indian Space Research Organisation (ISRO ) is India's national space agency, headquartered in Bengaluru, Karnataka. It serves as the principal research and development arm of the Department of Space (DoS), overseen by the Prime Minister of India, with the Chairman of ISRO also serving as the chief executive of the DoS. It is primarily responsible for space-based operations, space exploration, international space cooperation and the development of related technologies. The agency maintains a constellation of imaging, communications and remote sensing satellites. It operates the GAGAN and IRNSS satellite navigation systems. It has sent three missions to the Moon and one mission to Mars. Formerly known as the Indian National Committee for Space Research (INCOSPAR), ISRO was set up in 1962 by the Government of India on the recommendation of scientist Vikram Sarabhai. It was renamed as ISRO in 1969 and was subsumed into the Department of Atomic Energy (DAE). The establis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indian Remote Sensing Programme
India's remote sensing program was developed with the idea of applying space technologies for the benefit of humankind and the development of the country. The program involved the development of three principal capabilities. The first was to design, build and launch satellites to a Sun-synchronous orbit. The second was to establish and operate ground stations for spacecraft control, data transfer along with data processing and archival. The third was to use the data obtained for various applications on the ground. India demonstrated the ability of remote sensing for societal application by detecting coconut root-wilt disease from a helicopter mounted multispectral camera in 1970. This was followed by flying two experimental satellites, Bhaskara-1 in 1979 and Bhaskara-2 in 1981. These satellites carried optical and microwave payloads. India's remote sensing programme under the Indian Space Research Organization (ISRO) started off in 1988 with the IRS-1A, the first of the series ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indian Space Research Organisation
The Indian Space Research Organisation (ISRO ) is India's national List of government space agencies, space agency, headquartered in Bengaluru, Karnataka. It serves as the principal research and development arm of the Department of Space (DoS), overseen by the Prime Minister of India, with the Chairperson of the Indian Space Research Organisation, Chairman of ISRO also serving as the chief executive of the DoS. It is primarily responsible for space-based operations, space exploration, international space cooperation and the development of related technologies. The agency maintains a constellation of Earth observation satellite, imaging, Communications satellite, communications and remote sensing satellites. It operates the GPS-aided GEO augmented navigation, GAGAN and Indian Regional Navigation Satellite System, IRNSS satellite navigation systems. It has sent Chandrayaan programme, three missions to the Moon and Mars Orbiter Mission, one mission to Mars. Formerly known as the In ... [...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] |
Solar Panels On Spacecraft
Spacecraft operating in the inner Solar System usually rely on the use of power electronics-managed photovoltaic solar panels to derive electricity from sunlight. Outside the orbit of Jupiter, solar radiation is too weak to produce sufficient power within current solar technology and spacecraft mass limitations, so radioisotope thermoelectric generators (RTGs) are instead used as a power source.NASA JPL Publication: Basics of Space Flight, Chapter 11. Typical Onboard Systems, Electrical Power Supply and Distribution Subsystems, History The first practical silicon-based solar cells were introduced by Russell Shoemaker Ohl, a researcher at Bell Labs in 1940. It was only 1% efficient. In April 25, 1954 in Murray Hill, New Jersey. They demonstrated their solar panel by using it to power a small toy Ferris wheel and a solar powered radio transmitter. They were initially about 6% efficient, but improvements began to raise this number almost immediately. Bell had been interested in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spacecraft Attitude Control
Spacecraft attitude control is the process of controlling the orientation of a spacecraft (vehicle or satellite) with respect to an inertial frame of reference or another entity such as the celestial sphere, certain fields, and nearby objects, etc. Controlling vehicle attitude requires actuators to apply the torques needed to orient the vehicle to a desired attitude, and algorithms to command the actuators based on the current attitude and specification of a desired attitude. Before and during attitude control can be performed, spacecraft attitude determination must be performed, which requires sensors for absolute or relative measurement. The broader integrated field that studies the combination of sensors, actuators and algorithms is called ''guidance, navigation and control'', which also involves non-attitude concepts, such as position determination and navigation. Motivation A spacecraft's attitude must typically be stabilized and controlled for a variety of reasons. It ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reaction Wheel
A reaction wheel (RW) is an electric motor attached to a flywheel, which, when its rotation speed is changed, causes a counter-rotation proportionately through conservation of angular momentum. A reaction wheel can rotate only around its center of mass; it is not capable of moving from one place to another ( translational force). Reaction wheels are used primarily by spacecraft for three-axis attitude control, and do not require rockets or external applicators of torque, which reduces the mass fraction needed for fuel. They provide a high pointing accuracy, and are particularly useful when the spacecraft must be rotated by very small amounts, such as keeping a telescope pointed at a star. A reaction wheel is sometimes operated at a constant (or near-constant) rotation speed, to provide a satellite with a large amount of stored angular momentum. Doing so alters the spacecraft's rotational dynamics so that disturbance torques perpendicular to one axis of the satellite (the axis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth Observation Satellite
An Earth observation satellite or Earth remote sensing satellite is a satellite used or designed for Earth observation (EO) from orbit, including spy satellites and similar ones intended for non-military uses such as environmental monitoring, meteorology, cartography and others. The most common type are Earth imaging satellites, that take satellite images, analogous to aerial photographs; some EO satellites may perform remote sensing without forming pictures, such as in GNSS radio occultation. The first occurrence of satellite remote sensing can be dated to the launch of the first artificial satellite, Sputnik 1, by the Soviet Union on October 4, 1957. Sputnik 1 sent back radio signals, which scientists used to study the ionosphere. The United States Army Ballistic Missile Agency launched the first American satellite, Explorer 1, for NASA's Jet Propulsion Laboratory on January 31, 1958. The information sent back from its radiation detector led to the discovery of the Earth's Van ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Moment
In electromagnetism, the magnetic moment or magnetic dipole moment is the combination of strength and orientation of a magnet or other object or system that exerts a magnetic field. The magnetic dipole moment of an object determines the magnitude of torque the object experiences in a given magnetic field. When the same magnetic field is applied, objects with larger magnetic moments experience larger torques. The strength (and direction) of this torque depends not only on the magnitude of the magnetic moment but also on its orientation relative to the direction of the magnetic field. Its direction points from the south pole to the north pole of the magnet (i.e., inside the magnet). The magnetic moment also expresses the magnetic force effect of a magnet. The magnetic field of a magnetic dipole is proportional to its magnetic dipole moment. The dipole component of an object's magnetic field is symmetric about the direction of its magnetic dipole moment, and decreases as the inverse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Three-axis Stabilisation
Spacecraft attitude control is the process of controlling the orientation of a spacecraft (vehicle or satellite) with respect to an inertial frame of reference or another entity such as the celestial sphere, certain fields, and nearby objects, etc. Controlling vehicle attitude requires actuators to apply the torques needed to orient the vehicle to a desired attitude, and algorithms to command the actuators based on the current attitude and specification of a desired attitude. Before and during attitude control can be performed, spacecraft attitude determination must be performed, which requires sensors for absolute or relative measurement. The broader integrated field that studies the combination of sensors, actuators and algorithms is called '' guidance, navigation and control'', which also involves non-attitude concepts, such as position determination and navigation. Motivation A spacecraft's attitude must typically be stabilized and controlled for a variety of reasons. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Push Broom Scanner
A push broom scanner, also known as an along-track scanner, is a device for obtaining images with spectroscopic sensors. The scanners are regularly used for passive remote sensing from space, and in spectral analysis on production lines, for example with near-infrared spectroscopy used to identify contaminated food and feed. The moving scanner line in a traditional photocopier (or a scanner or facsimile machine) is also a familiar, everyday example of a push broom scanner. Push broom scanners and the whisk broom scanners variant (also known as across-track scanners) are often contrasted with staring arrays (such as in a digital camera), which image objects without scanning, and are more familiar to most people. In orbital push broom sensors, a line of sensors arranged perpendicular to the flight direction of the spacecraft is used. Different areas of the surface are imaged as the spacecraft flies forward. A push broom scanner can gather more light than a whisk broom scanner beca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
