|
Lunokhod 1
''Lunokhod 1'' (Russian language, Russian: Луноход-1 "Moonwalker 1"), also known as Аппарат 8ЕЛ № 203 ("Device 8EL No. 203") was the first rover (space exploration), robotic rover lunar rover, on the Moon and the first to freely move across the surface of an astronomical object beyond the Earth. Sent by the Soviet Union it was part of the robotic rovers Lunokhod program. The ''Luna 17'' spacecraft carried ''Lunokhod 1'' to the Moon in 1970. Lunokhod programme#Lunokhod 201, Lunokhod 0 (No.201), the previous and first attempt to land a rover, launched in February 1969 but failed to reach Earth orbit. Although only designed for a lifetime of three lunar days (approximately three Earth months), ''Lunokhod 1'' operated on the lunar surface for eleven lunar days (321 Earth days) and traversed a total distance of 10.54 km. Rover description ''Lunokhod 1'' was a lunar vehicle formed of a tub-like compartment with a large convex lid on eight independently powered w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lunar Rover
A lunar rover or Moon rover is a space exploration Rover (space exploration), vehicle designed to move across the surface of the Moon. The Apollo program's Lunar Roving Vehicle was driven on the Moon by members of three American crews, Apollo 15, Apollo 16, 16, and Apollo 17, 17. Other rovers have been partially or fully autonomous robots, such as the Soviet Union's Lunokhods, Chinese ''Yutu (rover), Yutus'', Indian ''Pragyan (Chandrayaan-3), Pragyan'', and Japan's Smart Lander for Investigating Moon#Rovers, LEVs. Five countries have had operating rovers on the Moon: the Soviet Union, the United States, China, India, and Japan. Variations in design Lunar rover designs have varied in several ways. Size and speed Lunokhod rovers were in length. The LRVs were long with a wheelbase, and achieved a top speed of during Apollo 17. Power The Lunokhod rovers, and others, used photovoltaic solar power. The LRV rovers were battery powered. Lunokhod and the Chinese ''Yutu'' rovers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lunar Soil
Lunar regolith is the unconsolidated material found on the selenography, surface of the Moon and in the Lunar atmosphere, Moon's tenuous atmosphere. Sometimes referred to as Lunar soil, Lunar soil specifically refers to the component of regolith smaller than 1 cm. It differs substantially in properties from Soil, terrestrial soil. As the Moon's fine surface layer, lunar regolith is picked up by even weak natural phenomena active at the Moon's surface, allowing it to be part of the Moon's scant atmosphere. It is easily disturbed and poses a significant hazard to exposed equipment and human health. The fine lunar regolith is made of sharp and very adhesive particles, with a distinct gunpowder taste and smell. Lunar regolith is prospected as a Lunar resources, lunar resource, particularly for lunar In situ resource utilization, in situ utilization, such as Lunarcrete, a lunar building material and regolith for Plants in space#Lunar surface, growing plants on the Moon. Lunar rego ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moon Landing
A Moon landing or lunar landing is the arrival of a spacecraft on the surface of the Moon, including both crewed and robotic missions. The first human-made object to touch the Moon was Luna 2 in 1959. In 1969 Apollo 11 was the first crewed mission to land on the Moon. There were List of Apollo missions#Crewed missions, six crewed landings between 1969 and 1972, and numerous uncrewed landings. All crewed missions to the Moon were conducted by the Apollo program, with the last departing the lunar surface in December 1972. After Luna 24 in 1976 there were no Soft landing (aeronautics), soft landings on the Moon until Chang'e 3 in 2013. All soft landings took place on the near side of the Moon until January 2019, when Chang'e 4 made the first landing on the far side of the Moon. Uncrewed landings Government landings Six government space agencies, Interkosmos, NASA, China National Space Administration, CNSA, Department of Space, DOS, JAXA and European Space Agency, ESA, ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lunar Orbit
In astronomy and spaceflight, a lunar orbit (also known as a selenocentric orbit) is an orbit by an object around Earth's Moon. In general these orbits are not circular. When farthest from the Moon (at apoapsis) a spacecraft is said to be at apolune, apocynthion, or aposelene. When closest to the Moon (at periapsis) it is said to be at perilune, pericynthion, or periselene. These derive from names or epithets of the moon goddess. Lunar orbit insertion (LOI) is an orbit insertion maneuver used to achieve lunar orbit. Low lunar orbit (LLO) is an orbit below altitude. These have a period of about 2 hours. They are of particular interest in the exploration of the Moon, but suffer from gravitational perturbations that make most unstable, and leave only a few orbital trajectories possible for indefinite '' frozen orbits''. These would be useful for long-term stays in LLO. Perturbation effects and low orbits Most lunar low orbits below 100 km (60 mi) are unstable. Gravitationa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parking Orbit
A parking orbit is a temporary orbit used during the launch of a spacecraft. A launch vehicle follows a trajectory to the parking orbit, then coasts for a while, then engines fire again to enter the final desired trajectory. An alternative trajectory that is used on some missions is ''direct injection'', where the rocket fires continuously (except during staging) until its fuel is exhausted, ending with the payload on the final trajectory. This technique was first used by the Soviet Venera 1 mission to Venus in 1961. Reasons for use Geostationary spacecraft Geostationary spacecraft require an orbit in the plane of the equator. Getting there requires a geostationary transfer orbit with an apogee directly above the equator. Unless the launch site itself is quite close to the equator, it requires an impractically large amount of fuel to launch a spacecraft directly into such an orbit. Instead, the craft is placed with an upper stage in an inclined parking orbit. When the craft c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operating Temperature
An operating temperature is the allowable temperature range of the local ambient environment at which an electrical or mechanical device operates. The device will operate effectively within a specified temperature range which varies based on the device function and application context, and ranges from the minimum operating temperature to the maximum operating temperature (or peak operating temperature). Outside this range of safe operating temperatures the device may fail. It is one component of reliability engineering. Similarly, biological systems have a viable temperature range, which might be referred to as an "operating temperature". Ranges Most semiconductor devices are manufactured in several temperature grades. Broadly accepted grades are: *Commercial: 0 °C to 70 °C () *Industrial: −40 °C to 85 °C () *Military: −55 °C to 125 °C () Nevertheless, each manufacturer defines its own temperature grades so designers must pay attention to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radioisotope Heater Unit
A radioisotope heater unit (RHU) is a small device that provides heat through radioactive decay. They are similar to tiny radioisotope thermoelectric generators (RTG) and normally provide about one watt of heat each, derived from the decay of a few grams of plutonium-238—although other radioactive isotopes could be used. The heat produced by these RHUs is given off continuously for several decades and, theoretically, for up to a century or more. In spacecraft, RHUs are used to keep other components at their operational temperatures, which may be very different to the temperature of other parts of the spacecraft. In the vacuum of space any part of the spacecraft which doesn't receive direct sunlight will cool down so much that electronics or delicate scientific instruments break down. They are simpler and more reliable than other ways of keeping components warm, such as electric heaters. Spacecraft use Most lunar and Martian surface probes use RHUs for heat, including ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polonium-210
Polonium-210 (210Po, Po-210, historically radium F) is an isotope of polonium. It undergoes alpha decay to stable 206Pb with a half-life of 138.376 days (about months), the longest half-life of all naturally occurring polonium isotopes (210–218Po). First identified in 1898, and also marking the discovery of the element polonium, 210Po is generated in the decay chain of uranium-238 and radium-226. 210Po is a prominent contaminant in the environment, mostly affecting seafood and tobacco. Its extreme toxicity is attributed to intense radioactivity, mostly due to alpha particles, which easily cause radiation damage, including cancer in surrounding tissue. The specific activity of is 166 TBq/g, i.e., . At the same time, 210Po is not readily detected by common radiation detectors, because its gamma rays have a very low energy. Therefore, can be considered as a quasi-pure alpha emitter. History In 1898, Marie and Pierre Curie discovered a strongly radioactive substance ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SVT2
SVT2 (SVT Två; commonly referred to as Tvåan), is one of the two main television channels broadcast by Sveriges Television in Sweden. Launched in 1969 by Sveriges Radio, the channel was until the 1990s the most watched in Sweden but now serves as SVT's specialist television network, carrying more highbrow and minority programming compared to the more mainstream SVT1. History TV2 Debate persisted throughout the 1960s over a second Swedish television channel, following the opening of ''Radiotjänst TV'' (later ''Sveriges Radio TV'') in 1956. Some wanted the new channel to be private and funded by advertising, or integrated to the existing channel; but it was decided that the public service broadcaster, Sveriges Radio, would take responsibility, by having two separate structures, one for each channel. Sweden was the second Nordic country to launch a second TV channel, after Finland who did it in March 1965. ''TV2'' began broadcasting on Friday 5 December 1969 - an occasion kn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Cell
A solar cell, also known as a photovoltaic cell (PV cell), is an electronic device that converts the energy of light directly into electricity by means of the photovoltaic effect.Solar Cells chemistryexplained.com It is a type of photoelectric cell, a device whose electrical characteristics (such as Electric current, current, voltage, or Electrical resistance and conductance, resistance) vary when it is exposed to light. Individual solar cell devices are often the electrical building blocks of solar panel, photovoltaic modules, known colloquially as "solar panels". Almost all commercial PV cells consist of crystalline silicon, with a market share of 95%. Cadmium telluride thin-film solar cells account for the remainder. The common single-junction silicon solar cell can produce a maximum open-circuit voltage o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lunar Day
A lunar day is the time it takes for Earth's Moon to complete on its axis one synodic rotation, meaning with respect to the Sun. Informally, a lunar day and a lunar night is each approximately 14 Earth days. The formal lunar day is therefore the time of a full lunar day-night cycle. Due to tidal locking, this equals the time that the Moon takes to complete one synodic orbit around Earth, a synodic lunar month, returning to the same lunar phase. The synodic period is about 29.53 Earth days, which is about 2.2 days longer than its sidereal period. Main definition Relative to the fixed stars on the celestial sphere, the Moon takes 27 Earth days, 7 hours, 43 minutes, 12 seconds to complete one orbit; however, since the Earth–Moon system advances around the Sun at the same time, the Moon must travel farther to return to the same phase. On average, this synodic period lasts 29 days, 12 hours, 44 minutes, 3 seconds, the length of a lunar month on Earth. The exact length ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
