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Microwave Radiometer (Juno)
Microwave Radiometer (MWR) is an instrument on the Juno (spacecraft), ''Juno'' orbiter sent to planet Jupiter. MWR is a multi-wavelength microwave radiometer for making observations of Jupiter's deep atmosphere. MWR can observe radiation from 1.37 to 50 cm in wavelength, from 600 MHz to 22 GHz in frequencies. This supports its goal of observing the previously unseen atmospheric features and chemical abundances hundreds of miles or kilometers into Jupiter's atmosphere. MWR is designed to detect six different frequencies in that range using separate antennas. MWR views Jupiter's microwave radiation so it can see up to hundreds of miles deep into the planet. In August 2016, as ''Juno'' swung closely by the planet MWR achieved a penetration of 200 to 250 miles (350 to 400 kilometers) below the surface cloud layer. MWR is designed to make observations below the cloud-tops, especially detecting the abundances of certain chemicals and determining dynamic features. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Juno Lifted By Overhead Crane
Juno commonly refers to: *Juno (mythology), the Roman goddess of marriage and queen of the gods * ''Juno'' (film), the 2007 film Juno may also refer to: Arts, entertainment and media Fictional characters *Juno, a character in the book ''Juno of Taris'' by Fleur Beale *Juno, a character in the film '' Jenny, Juno'' *Juno, a character in the film ''Beetlejuice'' *Juno, a character in the manga series ''Beastars'' *Juno, a character in the video game ''Assassin's Creed'' *Juno, a character in the video game '' The Banner Saga'' *Juno, a character in the video game '' Jet Force Gemini'' *Juno, a character in the video game '' Omega Strikers'' game * Juno (''Dune''), a character in the ''Dune'' universe * Juno (''Overwatch''), a character in the video game ''Overwatch 2'' and related franchise media *Juno Boyle, in the play '' Juno and the Paycock'' * Juno Eclipse, a character in the ''Star Wars Legends'' universe *Juno MacGuff, a character from ''Juno'' (film) *Juno Steel, a char ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonia
Ammonia is an inorganic chemical compound of nitrogen and hydrogen with the chemical formula, formula . A Binary compounds of hydrogen, stable binary hydride and the simplest pnictogen hydride, ammonia is a colourless gas with a distinctive pungent smell. It is widely used in fertilizers, refrigerants, explosives, cleaning agents, and is a precursor for numeous chemicals. Biologically, it is a common nitrogenous waste, and it contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to fertilisers. Around 70% of ammonia produced industrially is used to make fertilisers in various forms and composition, such as urea and diammonium phosphate. Ammonia in pure form is also applied directly into the soil. Ammonia, either directly or indirectly, is also a building block for the synthesis of many chemicals. In many countries, it is classified as an List of extremely hazardous substances, extremely hazardous substance. Ammonia is toxic, cau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jupiter's Great Red Spot In Microwave
Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a gas giant with a mass more than 2.5 times that of all the other planets in the Solar System combined and slightly less than one-thousandth the mass of the Sun. Its diameter is 11 times that of Earth and a tenth that of the Sun. Jupiter orbits the Sun at a distance of , with an orbital period of . It is the third-brightest natural object in the Earth's night sky, after the Moon and Venus, and has been observed since prehistoric times. Its name derives from that of Jupiter, the chief deity of ancient Roman religion. Jupiter was the first of the Sun's planets to form, and its inward migration during the primordial phase of the Solar System affected much of the formation history of the other planets. Jupiter's atmosphere consists of 76% hydrogen and 24% helium by mass, with a denser interior. It contains trace elements and compounds like carbon, oxygen, sulfur, neon, ammonia, water vapour, ph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slot Antenna
A slot antenna consists of a metal surface, usually a flat plate, with one or more holes or slots cut out. When the plate is driven element, driven as an antenna (radio), antenna by an applied radio frequency current, the slot radiates electromagnetic waves in a way similar to a dipole antenna. The shape and size of the slot, as well as the driving frequency, determine the radiation pattern. Slot antennas are usually used at Ultrahigh frequency, UHF and microwave frequencies at which wavelengths are small enough that the plate and slot are conveniently small. At these frequencies, the radio waves are often conducted by a waveguide, and the antenna consists of slots in the waveguide; this is called a slotted waveguide antenna. Multiple slots act as a directional antenna, directive array antenna and can emit a narrow fan-shaped beam of microwaves. They are used in standard laboratory microwave sources used for research, UHF television transmitting antennas, antennas on missile ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reflective Array Antenna
In telecommunications and radar, a reflective array antenna is a class of directive antennas in which multiple driven elements are mounted in front of a flat surface designed to reflect the radio waves in a desired direction. They are a type of array antenna. They are often used in the VHF and UHF frequency bands. VHF examples are generally large and resemble a highway billboard, so they are sometimes called billboard antennas. Other names are bedspring array and bowtie array depending on the type of elements making up the antenna. The curtain array is a larger version used by shortwave radio broadcasting stations. Reflective array antennas usually have a number of identical driven elements, fed in phase, in front of a flat, electrically large reflecting surface to produce a unidirectional beam of radio waves, increasing antenna gain and reducing radiation in unwanted directions. The larger the number of elements used, the higher the gain; the narrower the beam is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horn Antenna
A horn antenna or microwave horn is an antenna (radio), antenna that consists of a flaring metal waveguide shaped like a horn (acoustic), horn to direct radio waves in a beam. Horns are widely used as antennas at Ultrahigh frequency, UHF and microwave frequencies, above 300 MHz. They are used as Antenna feed, feed antennas (called feed horns) for larger antenna structures such as parabolic antennas, as standard calibration antennas to measure the Antenna gain, gain of other antennas, and as directive antennas for such devices as radar guns, Sliding door operator, automatic door openers, and microwave radiometers. Their advantages are moderate directivity, broad Bandwidth (signal processing), bandwidth, low losses, and simple construction and adjustment. One of the first horn antennas was constructed in 1897 by Bengali-Indian radio researcher Jagadish Chandra Bose in his pioneering experiments with microwaves. reprinted in The modern horn antenna was invented indepe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antenna Array
An antenna array (or array antenna) is a set of multiple connected antenna (radio), antennas which work together as a single antenna, to transmit or receive radio waves. The individual antennas (called ''elements'') are usually connected to a single radio receiver, receiver or transmitter by feedlines that feed the power to the elements in a specific phase (waves), phase relationship. The radio waves radiated by each individual antenna combine and Superposition principle, superpose, adding together (constructive interference, interfering constructively) to enhance the power radiated in desired directions, and cancelling (destructive interference, interfering destructively) to reduce the power radiated in other directions. Similarly, when used for receiving, the separate radio frequency currents from the individual antennas combine in the receiver with the correct phase relationship to enhance signals received from the desired directions and cancel signals from undesired directi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Patch Antenna
A patch antenna is a type of antenna with a low profile, usually consisting of a printed circuit board. It consists of a planar rectangular or circular sheet or "patch" of metal, mounted over a larger sheet of metal called a ground plane. It is the original type of microstrip antenna described by Howell in 1972. The two metal sheets together form a resonant piece of microstrip transmission line with a length of approximately one-half wavelength of the radio waves. The radiation mechanism arises from fringing fields along the radiating edges."Radiation from Microstrip Radiators," IEEE Transactions on Microwave Theory and Techniques, April 1969, Vol. 17, No. 4 pp.235-236 The radiation at the edges causes the antenna to act slightly larger electrically than its physical dimensions, so in order for the antenna to be resonant, a length of microstrip transmission line slightly shorter than one-half the wavelength at the frequency is used. The patch antenna is mainly practical at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spin-stabilisation
In aerospace engineering, spin stabilization is a method of stabilizing a satellite or launch vehicle by means of spin, i.e. rotation along the longitudinal axis. The concept originates from conservation of angular momentum as applied to ballistics, where the spin is commonly obtained by means of rifling. For most satellite applications this approach has been superseded by three-axis stabilization. Use Spin-stabilization is used on rockets and spacecraft where attitude control is required without the requirement for on-board 3-axis propulsion or mechanisms, and sensors for attitude control and pointing. On rockets with a solid motor upper stage, spin stabilization is used to keep the motor from drifting off course as they don't have their own thrusters. Usually small rockets are used to spin up the spacecraft and rocket then fire the rocket and send the craft off. Rockets and spacecraft that use spin stabilization: * The Jupiter-C and Minotaur V launch vehicles used spin-stab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galileo Probe
''Galileo'' was an American robotic space probe that studied the planet Jupiter and its moons, as well as the asteroids Gaspra and Ida. Named after the Italian astronomer Galileo Galilei, it consisted of an orbiter and an entry probe. It was delivered into Earth orbit on October 18, 1989, by , during STS-34. ''Galileo'' arrived at Jupiter on December 7, 1995, after gravitational assist flybys of Venus and Earth, and became the first spacecraft to orbit an outer planet. The Jet Propulsion Laboratory built the ''Galileo'' spacecraft and managed the ''Galileo'' program for NASA. West Germany's Messerschmitt-Bölkow-Blohm supplied the propulsion module. NASA's Ames Research Center managed the atmospheric probe, which was built by Hughes Aircraft Company. At launch, the orbiter and probe together had a mass of and stood tall. Spacecraft are normally stabilized either by spinning around a fixed axis or by maintaining a fixed orientation with reference to the Sun and a star. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
