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Ionization Blackout
In telecommunications, communications blackouts are * a cessation of communications or communications capability, caused by a lack of power to a communications facility or to communications equipment. * a total lack of radio communications capability, caused by ionospheric anomalies, e.g., during strong auroral activity or during re-entry of a spacecraft into the Earth's atmosphere. Technical failures Uptime being a key goal of most communications networks, power supplies and backup generators are typically used to ensure high-reliability power. Wireless networks may be subject to radio jamming; wired networks can be physically severed. Network design can also play a role in maintaining communications reliability; depending on the constraints in building a fiber-optic network, a self-healing ring topology may be used. Spacecraft reentry The communications blackouts that affect spacecraft re-entering the Earth's atmosphere, which are also known as radio blackouts, ionizat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunications
Telecommunication, often used in its plural form or abbreviated as telecom, is the transmission of information over a distance using electronic means, typically through cables, radio waves, or other communication technologies. These means of transmission may be divided into communication channels for multiplexing, allowing for a single medium to transmit several concurrent Session (computer science), communication sessions. Long-distance technologies invented during the 20th and 21st centuries generally use electric power, and include the electrical telegraph, telegraph, telephone, television, and radio. Early telecommunication networks used metal wires as the medium for transmitting signals. These networks were used for telegraphy and telephony for many decades. In the first decade of the 20th century, a revolution in wireless communication began with breakthroughs including those made in radio communications by Guglielmo Marconi, who won the 1909 Nobel Prize in Physics. Othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gemini 2
Gemini 2 (Gemini-Titan 2; GT-2) was the second spaceflight of the American human spaceflight program Project Gemini, and was launched and recovered on January 19, 1965. Gemini 2, like Gemini 1, was an uncrewed mission intended as a test flight of the Gemini spacecraft. Unlike Gemini 1, which was placed into orbit, Gemini 2 made a suborbital flight, primarily intended to test the spacecraft's heat shield. It was launched on a Titan II GLV rocket. The spacecraft used for the Gemini 2 mission was later refurbished into the Gemini B configuration, and was subsequently launched on another suborbital flight, along with OPS 0855, as a test for the US Air Force Manned Orbital Laboratory. Gemini spacecraft no. 2 was the first craft to make more than one spaceflight since the X-15, and the only one until Space Shuttle ''Columbia'' flew its second mission in 1981; it would also be the only space capsule to be reused until Crew Dragon ''Endeavour'' was launched a second time i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Oceanic And Atmospheric Administration
The National Oceanic and Atmospheric Administration (NOAA ) is an American scientific and regulatory agency charged with Weather forecasting, forecasting weather, monitoring oceanic and atmospheric conditions, Hydrography, charting the seas, conducting deep-sea exploration, and managing fishing and protection of marine mammals and endangered species in the US exclusive economic zone. The agency is part of the United States Department of Commerce and is headquartered in Silver Spring, Maryland. History NOAA traces its history back to multiple agencies, some of which are among the earliest in the federal government: * United States Coast and Geodetic Survey, formed in 1807 * National Weather Service, Weather Bureau of the United States, formed in 1870 * United States Fish Commission, Bureau of Commercial Fisheries, formed in 1871 (research fleet only) * NOAA Commissioned Corps, Coast and Geodetic Survey Corps, formed in 1917 The most direct predecessor of NOAA was the Enviro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Flare
A solar flare is a relatively intense, localized emission of electromagnetic radiation in the Sun's atmosphere. Flares occur in active regions and are often, but not always, accompanied by coronal mass ejections, solar particle events, and other eruptive solar phenomena. The occurrence of solar flares varies with the 11-year solar cycle. Solar flares are thought to occur when stored magnetic energy in the Sun's atmosphere accelerates charged particles in the surrounding plasma. This results in the emission of electromagnetic radiation across the electromagnetic spectrum. The typical time profile of these emissions features three identifiable phases: a ''precursor phase'', an ''impulsive phase'' when particle acceleration dominates, and a ''gradual phase'' in which hot plasma injected into the corona by the flare cools by a combination of radiation and conduction of energy back down to the lower atmosphere. The extreme ultraviolet and X-ray radiation from solar flares is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Shuttle
The Space Shuttle is a retired, partially reusable launch system, reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. Its official program name was the Space Transportation System (STS), taken from the 1969 plan led by U.S. vice president Spiro Agnew for a system of reusable spacecraft where it was the only item funded for development. The first (STS-1) of four orbital test flights occurred in 1981, leading to operational flights (STS-5) beginning in 1982. Five complete Space Shuttle orbiter vehicles were built and flown on a total of 135 missions from 1981 to 2011. They launched from the Kennedy Space Center (KSC) in Florida. Operational missions launched numerous satellites, interplanetary probes, and the Hubble Space Telescope (HST), conducted science experiments in orbit, participated in the Shuttle–Mir program, Shuttle-''Mir'' program with Russia, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tracking And Data Relay Satellite System
The U.S. Tracking and Data Relay Satellite System (TDRSS, pronounced "T-driss") is a network of American communications satellites (each called a tracking and data relay satellite, TDRS) and ground stations used by NASA for space communications. The system was designed to replace an existing network of ground stations that had supported all of NASA's crewed flight missions. The prime design goal was to increase the time spacecraft were in communication with the ground and improve the amount of data that could be transferred. Many Tracking and Data Relay Satellites were launched in the 1980s and 1990s with the Space Shuttle and made use of the Inertial Upper Stage, a two-stage solid rocket booster developed for the shuttle. Other TDRS were launched by Atlas IIa and Atlas V rockets. The most recent generation of satellites provides ground reception rates of 6 Mbit/s in the S-band and 800 Mbit/s in the Ku band, Ku- and Ka band, Ka-bands. This is mainly used by the United S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titan (moon)
Titan is the largest moon of Saturn and the List of Solar System objects by size, second-largest in the Solar System. It is the only Natural satellite, moon known to have an atmosphere denser than the Atmosphere of Earth, Earth's and is the only known object in space—other than Earth—on which there is clear evidence that stable bodies of liquid exist. Titan is one of seven List of gravitationally rounded objects of the Solar System, gravitationally rounded moons of Saturn and the second-most distant among them. Frequently described as a Planetary-mass moon, planet-like moon, Titan is 50% larger in diameter than Earth's Moon and 80% more Mass, massive. It is the second-largest moon in the Solar System after Jupiter's Ganymede (moon), Ganymede and is larger than Mercury (planet), Mercury; yet Titan is only 40% as massive as Mercury, because Mercury is mainly iron and rock while much of Titan is ice, which is less dense. Discovered in 1655 by the Dutch astronomer Christiaan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Huygens Probe
''Huygens'' ( ) was an atmospheric entry robotic space probe that landed successfully on Saturn's moon Titan in 2005. Built and operated by the European Space Agency (ESA), launched by NASA, it was part of the ''Cassini–Huygens'' mission and became the first spacecraft to land on Titan and the farthest landing from Earth a spacecraft has ever made. The probe was named after the 17th-century Dutch astronomer Christiaan Huygens, who discovered Titan in 1655. The combined ''Cassini–Huygens'' spacecraft was launched from Earth on 15 October 1997. ''Huygens'' separated from the ''Cassini'' orbiter on 25 December 2004, and landed on Titan on 14 January 2005 near the Adiri region. ''Huygens''s landing is so far the only one accomplished in the outer Solar System and on a moon other than Earth's. ''Huygens'' touched down on land, although the possibility that it would touch down in an ocean was also taken into account in its design. The probe was designed to gather data for a few ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mars Pathfinder
''Mars Pathfinder'' was an American robotic spacecraft that landed a base station with a rover (space exploration), roving probe on Mars in 1997. It consisted of a Lander (spacecraft), lander, renamed the Carl Sagan Memorial Station, and a lightweight, wheeled robotic Mars rover named ''Sojourner (rover), Sojourner'', the first rover to operate outside the Earth–Moon system. The mission terminated in 1998. Launched on December 4, 1996, by NASA aboard a Delta II booster a month after the ''Mars Global Surveyor'', it landed on July 4, 1997, on Mars's Ares Vallis, in a region called Chryse Planitia in the Oxia Palus quadrangle. The lander (spacecraft), lander then opened, exposing the rover which conducted many experiments on the Martian surface. The mission carried a series of scientific instruments to analyze the Martian Celestial body atmosphere, atmosphere, climate, and geology and the composition of its rock (geology), rocks and soil. It was the second project from NASA's D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smithsonian Institution
The Smithsonian Institution ( ), or simply the Smithsonian, is a group of museums, Education center, education and Research institute, research centers, created by the Federal government of the United States, U.S. government "for the increase and diffusion of knowledge". Founded on August 10, 1846, it operates as a trust instrumentality and is not formally a part of any of the Federal government of the United States#branches, three branches of the federal government. The institution is named after its founding donor, British scientist James Smithson. It was originally organized as the United States National Museum, but that name ceased to exist administratively in 1967. The Smithsonian Institution has historical holdings of over 157 million items, 21 museums, 21 libraries, 14 education and research centers, a zoo, and historical and architectural landmarks, mostly located in Washington, D.C. Additional facilities are located in Maryland, New York (state), New York, and Virg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air & Space
''Air & Space/Smithsonian'' was a quarterly magazine published by the National Air and Space Museum in Washington, D.C. Washington, D.C., formally the District of Columbia and commonly known as Washington or D.C., is the capital city and federal district of the United States. The city is on the Potomac River, across from Virginia, and shares land borders with ..., United States. Its first publication was in April 1986. Articles in the magazine involve topics related to historical and present aviation and space travel. It also covers military aviation and aeronautical technology. References External links * 1986 establishments in Washington, D.C. Aviation magazines published in the United States Bimonthly magazines published in the United States History magazines published in the United States Magazines established in 1986 Magazines published in Washington, D.C. Smithsonian Institution publications {{hist-mag-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
