Misplaced Pages

#375624

27-642: Resurs-DK No.1 , also called Resurs-DK1 , was a commercial Earth observation satellite capable of transmitting high-resolution imagery (up to 0.9 m) to the ground stations as it passed overhead. The spacecraft was operated by NTs OMZ , the Russian Research Center for Earth Operative Monitoring. The satellite was designed for multi-spectral remote sensing of the Earth's surface aimed at acquiring high-quality visible images in near real-time as well as on-line data delivery via radio link and providing

54-440: A satellite to hover over a constant spot on the earth since the orbital period at this altitude is 24 hours. This allows uninterrupted coverage of more than 1/3 of the Earth per satellite, so three satellites, spaced 120° apart, can cover the whole Earth. This type of orbit is mainly used for meteorological satellites . Herman Potočnik explored the idea of using orbiting spacecraft for detailed peaceful and military observation of

81-571: A wide range of consumers with value-added processed data. The Russian space tracking service, ASPOS OKP, reported that the spacecraft's onboard systems and attitude control had been terminated in February 2016. Tracking of the satellite was discontinued on 1 March 2016. The Resurs-DK spacecraft was built by the Russian space company TsSKB-Progress in Samara , Russia. It was a modified version of

108-562: Is Russian for "Resource". The letters DK are the initials of Dmitry Kozlov , chief designer of the first satellite of the Yantar-2K class. Made by Vavilov State Optical Institute , Russia [1] Archived 3 March 2016 at the Wayback Machine . It was not possible to represent an image in true-color because there was no blue band (0.4 - 0.5 μm). However, it was possible to combine red, green and near infrared in such way that

135-531: Is a type of satellite that is primarily used to monitor the weather and climate of the Earth . These meteorological satellites, however, see more than clouds and cloud systems. City lights, fires , effects of pollution , auroras , sand and dust storms , snow cover, ice mapping, boundaries of ocean currents , energy flows, etc., are other types of environmental information collected using weather satellites. Weather satellite images helped in monitoring

162-519: Is classified in accordance with ITU Radio Regulations (article 1) as follows: Fixed service (article 1.20) The allocation of radio frequencies is provided according to Article 5 of the ITU Radio Regulations (edition 2012). In order to improve harmonisation in spectrum utilisation, the majority of service-allocations stipulated in this document were incorporated in national Tables of Frequency Allocations and Utilisations which

189-461: Is dark blue to black while shallow waters or waters with high sediment concentrations are lighter blue. Urban areas will appear blue towards gray. Clouds and snow are white. Unit featured 4 TDI ( Time Delay and Integration ) sensor arrays, one panchromatic and three multispectral. Each sensor array was composed of 36 "Kruiz" CCD chips. Effective length of the single array was about 36000 pixels. Arrays were grouped in 3 separated lines: This separation

216-421: Is displayed in green, and the green is displayed in blue. This combination is favoured by scientists because near IR is useful for detection of numerous vegetation types. Vegetation appear as redtones, the brighter the red, the healthier the vegetation. Soils with no or sparse vegetation range from white (sand, salt) to greens or browns depending on moisture and organic matter content. Water appears blue, clear water

243-427: Is with-in the responsibility of the appropriate national administration. The allocation might be primary, secondary, exclusive, and shared. However, military usage, in bands where there is civil usage, will be in accordance with the ITU Radio Regulations. Satellite revisit period The satellite revisit period is the time elapsed between observations of the same point on Earth by a satellite . It depends on

270-579: The Cold War prompted the rapid development of Satellite launch systems and camera technology capable of sufficient Earth observation to garner intelligence on enemy military infrastructure and evaluate nuclear posture. Following the U-2 incident in 1960, which highlighted the risks of aerial spying, the U.S. accelerated surveillance satellite programs like CORONA . Satellites largely replaced aircraft overflights for surveillance after 1960. A weather satellite

297-536: The MetOp spacecraft of EUMETSAT are all operated at altitudes of about 800 km (500 mi). The Proba-1 , Proba-2 and SMOS spacecraft of European Space Agency are observing the Earth from an altitude of about 700 km (430 mi). The Earth observation satellites of UAE, DubaiSat-1 & DubaiSat-2 are also placed in Low Earth orbits (LEO) orbits and providing satellite imagery of various parts of

SECTION 10

#1732788093376

324-531: The Earth. To get global coverage with a low orbit, a polar orbit is used. A low orbit will have an orbital period of roughly 100 minutes and the Earth will rotate around its polar axis about 25° between successive orbits. The ground track moves towards the west 25° each orbit, allowing a different section of the globe to be scanned with each orbit. Most are in Sun-synchronous orbits . A geostationary orbit , at 36,000 km (22,000 mi), allows

351-399: The appearance of the displayed image resembles a visible colour photograph, i.e. vegetation in green, water in blue, soil in brown. This was not always possible because two similarly coloured objects can have completely different reactions to near IR light. Green, red and near IR are typically combined to make a traditional false color composite where the near IR is displayed in red, the red

378-583: The current vegetation state to its long term average. For example, the 2002 oil spill off the northwest coast of Spain was watched carefully by the European ENVISAT , which, though not a weather satellite, flies an instrument (ASAR) which can see changes in the sea surface. Anthropogenic emissions can be monitored by evaluating data of tropospheric NO 2 and SO 2 . These types of satellites are almost always in Sun-synchronous and "frozen" orbits. A Sun-synchronous orbit passes over each spot on

405-495: The discovery of the Earth's Van Allen radiation belts . The TIROS-1 spacecraft, launched on April 1, 1960, as part of NASA's Television Infrared Observation Satellite (TIROS) program, sent back the first television footage of weather patterns to be taken from space. In 2008, more than 150 Earth observation satellites were in orbit, recording data with both passive and active sensors and acquiring more than 10 terabits of data daily. By 2021, that total had grown to over 950, with

432-460: The ground at the same time of day, so that observations from each pass can be more easily compared, since the Sun is in the same spot in each observation. A "frozen" orbit is the closest possible orbit to a circular orbit that is undisturbed by the oblateness of the Earth , gravitational attraction from the Sun and Moon, solar radiation pressure , and air drag . Terrain can be mapped from space with

459-494: The ground in his 1928 book, The Problem of Space Travel . He described how the special conditions of space could be useful for scientific experiments. The book described geostationary satellites (first put forward by Konstantin Tsiolkovsky ) and discussed communication between them and the ground using radio, but fell short of the idea of using satellites for mass broadcasting and as telecommunications relays. The onset of

486-461: The largest number of satellites operated by US-based company Planet Labs . Most Earth observation satellites carry instruments that should be operated at a relatively low altitude. Most orbit at altitudes above 500 to 600 kilometers (310 to 370 mi). Lower orbits have significant air-drag , which makes frequent orbit reboost maneuvers necessary. The Earth observation satellites ERS-1, ERS-2 and Envisat of European Space Agency as well as

513-465: 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

540-430: The military reconnaissance satellite Yantar-4KS1 (Terilen). The spacecraft was three-axis stabilized. The design lifetime was no less than three years, with an expected lifetime of five years. Ground location accuracy was 100 m (330 ft). Onboard storage was 768 gigabits. Data link speed to the ground station was 300 Mbit/s . Maximum daily productivity was 1,000,000 km (390,000 sq mi). Resurs

567-425: The satellite's orbit , target location, and swath of the sensor. "Revisit" is related to the same ground trace , a projection of the satellite's orbit on to the Earth. Revisit requires a very close repeat of the ground trace. In the case of polar orbit or highly inclined low-Earth-orbit reconnaissance satellites , the sensor must have the variable swath, to look longitudinally (east-west, or sideways) at

SECTION 20

#1732788093376

594-740: The use of satellites, such as Radarsat-1 and TerraSAR-X . According to the International Telecommunication Union (ITU), Earth exploration-satellite service (also: Earth exploration-satellite radiocommunication service ) is – according to Article 1.51 of the ITU Radio Regulations (RR) – defined as: A radiocommunication service between earth stations and one or more space stations , which may include links between space stations, in which: This service may also include feeder links necessary for its operation. This radiocommunication service

621-478: 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. Other environmental satellites can assist environmental monitoring by detecting changes in the Earth's vegetation, atmospheric trace gas content, sea state, ocean color, and ice fields. By monitoring vegetation changes over time, droughts can be monitored by comparing

648-412: Was 5 to 7 days off-nadir. Swath width at the altitude of 350 km: Russian research hardware for detection of high-energy electrons and protons, their identification, detection of high-energy particle bursts – earthquake signs. PAMELA, Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics was an attached module built by Italian researchers with international partners. Its purpose

675-425: Was basic physics research of primary cosmic rays . The satellite was initially placed in a 355 km × 573 km (221 mi × 356 mi) orbit in 2006. On 10 September 2010, its orbit was circularised to 567 km × 573 km (352 mi × 356 mi), with an inclination of 69.9°. Earth observation satellite The first occurrence of satellite remote sensing can be dated to

702-416: Was causing a time delay of the colour images combined from green, red and near infrared, so fast-moving objects were shown in triplets. Moving object speed and direction could be calculated. All 4 arrays could work simultaneously, so it was possible to combine panchromatic and 3 multispectral images in one pansharpened color composite. The system used 10-bit analog-to-digital converters . Focal Plane Unit

729-424: Was made by NPO Opteks, Russia [2] . The CCD "Kruiz" was a 1024 pixel x 128 line, high speed TDI sensor. The active imaging area was organized as 1024 vertical columns and 128 horizontal TDI rows. [3] Designed jointly by NPO Opteks and ELECTRON-OPTRONIC. Produced by ELECTRON-OPTRONIC (now is ELAR [4] ) At the altitude of 360 km: At the altitude of 604 km: 1.5–2.0 m [5] The revisit rate

#375624