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32-413: WorldView-4 , previously known as GeoEye-2 , was a third generation commercial Earth observation satellite launched on 11 November 2016, at 18:30:33 UTC . The spacecraft was operated by DigitalGlobe . With a maximum resolution of 31 cm (12 in), WorldView-4 provided similar imagery as WorldView-3 , the highest resolution commercially available at the time of its launch. The spacecraft suffered

64-523: A failure in one of its control moment gyroscopes in January 2019, and operations were unable to be recovered. It reentered over New Zealand on 30 November 2021. Work on GeoEye-2 began in October 2007 when commercial imagery company GeoEye selected ITT Corporation to begin work on long lead-time items for the satellite camera system. In March 2010, an initial contract for construction of the spacecraft

96-421: A highest resolution of 31 cm/px between 450 and 800 nanometres , and multispectral images at 124 cm/ px in blue, green, red and near-infrared channels (450-510 nm, 510-580 nm, 655-690 nm and 780-920 nm, respectively). Earth observation satellite The first occurrence of satellite remote sensing can be dated to the launch of the first artificial satellite, Sputnik 1 , by

128-466: A moderate rate of spread. As the fire continued to spread, firefighters were faced with a number of unique challenges. Base officials warned that there was possibly unexploded ordnance that was left over from the days when the base was used during World War II and the Korean War . By the morning of September 20, the fire had been estimated at 10,542 acres (42.7 km ) in size with only 18% of

160-540: 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 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

192-399: A remote canyon on the southern half of the base, access was difficult for fire crews. On September 18 the fire jumped to over 2,200 acres (8.9 km ) prompting evacuation warnings for homes on San Miguelito Canyon south of Lompoc and east of the base. By mid-afternoon on September 19 the fire had grown to over 4,528 acres (18.3 km ) and with no containment was continuing to burn with

224-519: 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

256-488: Is estimated at US$ 835 million. The first public image from WorldView-4 was taken on 26 November 2016 and released on 2 December 2016. In January 2019, WorldView-4 was announced to have suffered a failure in one of its control moment gyroscopes , and was considered no longer usable. WorldView-4 was insured against satellite failure, and in spring 2019 the company owning the satellite, Maxar Technologies , which had acquired DigitalGlobe in 2017, announced that they had received

288-509: 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. Canyon Fire (2016) The Canyon Fire was a wildfire that burned on Vandenberg Space Force Base in Santa Barbara County , California during September 2016. By

320-708: The InSight Mars lander, which was delayed until 2018. The launch vehicle had been erected at the Vandenberg launch pad on 16 December 2015 for the InSight mission; after the WorldView-4 mission took the place of InSight , the launch vehicle was allowed to remain vertical at the pad protected by its mobile service tower . The WorldView-4 payload was fixed atop the rocket during the second week of September 2016. Originally scheduled for launch on 29 June 2016,

352-655: The WorldView-4 earth observation satellite that was set to launch on September 18 from Vandenberg AFB Space Launch Complex 3 had to be delayed. According to the Emergency Operations Center commander, base procedures require firefighting crews to be standing by for every launch, thus the launch was delayed so that all resources could concentrate on the growing fire. While all fires at Vandenberg were contained by September 27, facilities and instrumentation needed to be surveyed for damage and, due to

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384-610: 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 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

416-604: 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 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

448-605: The company announced the completion of the system's critical design review on 1 March 2011. The system was delivered to Lockheed Martin in April 2012, and was mated to the satellite bus the following month. DigitalGlobe agreed to purchase GeoEye in July 2012, and finalized the merger in January 2013. At the time, each company had a satellite being prepared for launch: WorldView-3 and GeoEye-2 . Because WorldView-3 offered multiple short-wavelength infrared channels in addition to

480-647: 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

512-434: The fire contained. On September 21, a Ventura County OES water tender assigned to the fire crashed on Highway 246 just outside Lompoc. The crash killed one firefighter and sent the second to the hospital with minor injuries. The individual was identified as engineer Ryan Osler. The fire was fully contained on September 24 after burning 12,742 acres (51.6 km ). A United Launch Alliance Atlas V carrying

544-455: 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 the largest number of satellites operated by US-based company Planet Labs . Most Earth observation satellites carry instruments that should be operated at

576-400: The flight was rescheduled to 15 September 2016 and then to 16 September 2016. During countdown on 16 September 2016, the launch was scrubbed due to a liquid hydrogen leak in the ground support equipment resulting in an ice ball forming on an umbilical cable . The launch was rescheduled for 18 September 2016 to allow for the replacement of a fill-and-drain valve, determined to be the cause of

608-412: The full US$ 183 million insurance payment. WorldView-4 was launched on 11 November 2016 at 18:30:33 UTC from Vandenberg Air Force Base Space Launch Complex 3E aboard an Atlas V launch vehicle . The launch vehicle launched in the 401 configuration with serial number AV-062, and was provided and administered by United Launch Alliance . This was the same launch vehicle that had been scheduled to launch

640-460: 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

672-525: The ground using radio, but fell short of the idea of using satellites for mass broadcasting and as telecommunications relays. The onset of 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

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704-554: The launch date was reset to 6 November 2016. The date was later pushed back to 11 November 2016 as ULA worked to fix "minor Atlas V booster issues" found during preparations. The spacecraft's telescope was called the GeoEye Imaging System-2, also known as SpaceView 110, which was designed and built by ITT Corporation (later ITT Exelis and Harris Corporation ). The telescope mirror was 1.1 m (3 ft 7 in) in diameter. It provided panchromatic images at

736-435: The launch to no earlier than October 2016. Four additional fires of varying sizes broke out between 22 and 27 September 2016; while all were contained by the end of the 27th, base commander John Moss stated that until all facilities and instrumentation could be surveyed, no preliminary launch date could be determined. Repairs were made to the base's infrastructure affected by the wildfire, including power and communications, and

768-566: The leak. The Canyon Fire , a wildfire that burned over 5,157 ha (12,742 acres) on the southern section of Vandenberg , resulted in a further launch delay so that the base could "concentrate [their] resources on the situation at hand". As a result of scheduling availability on the Western Range , the flight was rescheduled for 26 September 2016. Continued efforts in fighting the Canyon Fire caused an indeterminate delay of

800-728: 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 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

832-445: The standard panchromatic and multiwavelength channels, the company chose to proceed with its launch and to place GeoEye-2 into storage. In July 2014, DigitalGlobe announced that GeoEye-2 had been renamed to WorldView-4 to better match the company's branding, and that, due to a projected increase in product demand, the spacecraft's launch had been scheduled for mid-2016. The total cost of the spacecraft, including insurance and launch,

864-469: The time the fire was contained on September 24, it had burned 12,742 acres (51.6 km ) of land. Due to the nature of the activities that take place on the Base, there were a number of unique challenges posed during the fire including the presence of potentially hazardous materials. The fire broke out September 17 and quickly grew to over 500 acres (2.0 km ). Due to the location of the fire, burning in

896-740: 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

928-478: 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

960-445: 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 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

992-552: 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 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

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1024-695: Was awarded to Lockheed Martin Space Systems , which previously built the Ikonos imaging satellite. At the time, GeoEye-2 was planned for launch in late 2012. The spacecraft's preliminary design review was completed in November 2010, while its critical design review (CDR) was completed in June 2011. Lockheed Martin issued a contract to ITT Corporation in August 2010 to continue work on the camera system, and

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