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Pioneer 11
''Pioneer 11'' (also known as ''Pioneer G'') is a NASA robotic space probe launched on April 5, 1973, to study the asteroid belt, the environment around Jupiter and Saturn, the solar wind, and cosmic rays. It was the first probe to Exploration of Saturn, encounter Saturn, the second to fly through the Asteroid belt#Exploration, asteroid belt, and the second to fly by Jupiter. Later, ''Pioneer 11'' became the List of artificial objects leaving the Solar System, second of five artificial objects to achieve an escape velocity allowing it to Solar System#Farthest regions, leave the Solar System. Due to power constraints and the vast distance to the probe, the last routine contact with the spacecraft was on September 30, 1995, and the last good engineering data was received on November 24, 1995. Mission background History Approved in February 1969, ''Pioneer 11'' and its twin probe, ''Pioneer 10'', were the first to be designed for exploring the outer Solar System. Yielding to multip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States's civil list of government space agencies, space program, aeronautics research and outer space, space research. National Aeronautics and Space Act, Established in 1958, it succeeded the National Advisory Committee for Aeronautics (NACA) to give the American space development effort a distinct civilian orientation, emphasizing peaceful applications in space science. It has since led most of America's space exploration programs, including Project Mercury, Project Gemini, the 1968–1972 Apollo program missions, the Skylab space station, and the Space Shuttle. Currently, NASA supports the International Space Station (ISS) along with the Commercial Crew Program and oversees the development of the Orion (spacecraft), Orion spacecraft and the Sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Asteroid Belt
The asteroid belt is a torus-shaped region in the Solar System, centered on the Sun and roughly spanning the space between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies called asteroids or minor planets. The identified objects are of many sizes, but much smaller than planets, and, on average, are about one million kilometers (or six hundred thousand miles) apart. This asteroid belt is also called the main asteroid belt or main belt to distinguish it from other asteroid populations in the Solar System. The asteroid belt is the smallest and innermost circumstellar disc in the Solar System. Classes of Small Solar System body, small Solar System bodies in other regions are the near-Earth objects, the Centaur (minor planet), centaurs, the Kuiper belt objects, the scattered disc objects, the sednoids, and the Oort cloud objects. About 60% of the main belt mass is contained in the four largest asteroids: Ceres (dwarf planet), C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Pioneer H
Pioneer H was a proposed space probe for the US Pioneer program. If it had been approved, it would have been launched in 1974 and have been designated Pioneer 12; that designation was later applied to the ''Pioneer Venus Orbiter''. History As planning for the ''Pioneer 10'' and '' 11'' missions progressed, mission scientists found themselves desiring a third probe. In 1971, a formal mission study was proposed for a spacecraft to be launched to Jupiter in 1974, where it would use the gas giant as a gravitational slingshot to travel outside the ecliptic. This was the first Out-Of-The-Ecliptic mission (OOE) proposed, for Jupiter and solar (Sun) observations. NASA/Ames Research Center would have managed the project. The NASA contractor TRW Systems Group (formerly Space Technology Laboratories) would have constructed the Pioneer H probe from the flight-qualified spare components intended for the Pioneer F and G probes (designated ''Pioneer 10'' and ''Pioneer 11'' after launch) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
NASA Ames Research Center
The Ames Research Center (ARC), also known as NASA Ames, is a major NASA research center at Moffett Federal Airfield in California's Silicon Valley. It was founded in 1939 as the second National Advisory Committee for Aeronautics (NACA) laboratory. That agency was dissolved and its assets and personnel transferred to the newly created National Aeronautics and Space Administration (NASA) on October 1, 1958. NASA Ames is named in honor of Joseph Sweetman Ames, a physicist and one of the founding members of NACA. At last estimate NASA Ames had over US$3 billion in capital equipment, 2,300 research personnel and a US$750 million annual budget. Ames was founded to conduct wind-tunnel research on the aerodynamics of propeller-driven aircraft; however, its role has expanded to encompass spaceflight and information technology. Ames plays a role in many NASA missions. It provides leadership in astrobiology; small satellites; robotic lunar exploration; the search for habitable planets; s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Voyager Program
The Voyager program is an American scientific program that employs two interstellar probes, ''Voyager 1'' and ''Voyager 2''. They were launched in 1977 to take advantage of a favorable planetary alignment to explore the two gas giants Jupiter and Saturn and potentially also the ice giants, Uranus and Neptune—to Flyby (spaceflight), fly near them while collecting data for transmission back to Earth. After ''Voyager 1'' successfully completed its flyby of Saturn and its moon Titan (moon), Titan, it was decided to send ''Voyager 2'' on flybys of Uranus and Neptune. After the planetary flybys were complete, decisions were made to keep the probes in operation to explore Outer space, interstellar space and the outer regions of the Solar System. On 25 August 2012, data from ''Voyager 1'' indicated that it had entered interstellar space. On 5 November 2019, data from ''Voyager 2'' indicated that it also had entered interstellar space. On 4 November 2019, scientists reported that on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Saturnian System
The moons of Saturn are numerous and diverse, ranging from tiny moonlets only tens of meters across to the enormous Titan (moon), Titan, which is larger than the planet Mercury (planet), Mercury. There are 274 natural satellite, moons with confirmed orbits, the most of any planet in the Solar System. This number does not include the many thousands of moonlets embedded within Rings of Saturn, Saturn's dense rings, nor hundreds of possible kilometer-sized distant moons that have been observed on single occasions. Three moons are particularly notable. Titan is the second-List of natural satellites, largest moon in the Solar System (after Jupiter's Ganymede (moon), Ganymede), with a Atmosphere of Titan#Composition, nitrogen-rich Earth-like Atmosphere of Titan, atmosphere and a landscape featuring river networks and lakes of Titan, hydrocarbon lakes. Enceladus emits jets of ice from its south-polar region and is covered in a deep layer of snow. Iapetus (moon), Iapetus has contrasting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Radio Occultation
Radio occultation (RO) is a remote sensing technique used for measuring the physical properties of a planetary atmosphere or ring system. Satellites carrying onboard GNSS-Radio occultation instruments include CHAMP, GRACE and GRACE-FO, MetOp and the recently launched COSMIC-2. Atmospheric radio occultation Atmospheric radio occultation relies on the detection of a change in a radio signal as it passes through a planet's atmosphere, i.e. as it is occulted by the atmosphere. When electromagnetic radiation passes through the atmosphere, it is refracted (or bent). The magnitude of the refraction depends on the gradient of refractivity normal to the path, which in turn depends on the density gradient. The effect is most pronounced when the radiation traverses a long atmospheric limb path. At radio frequencies the amount of bending cannot be measured directly; instead, the bending can be calculated using the Doppler shift of the signal given the geometry of the emitter and receiver. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Atmosphere Of Saturn
Saturn is the sixth planet from the Sun and the second largest in the Solar System, after Jupiter. It is a gas giant, with an average radius of about 9 times that of Earth. It has an eighth the average density of Earth, but is over 95 times more massive. Even though Saturn is almost as big as Jupiter, Saturn has less than a third its mass. Saturn orbits the Sun at a distance of , with an orbital period of 29.45 years. Saturn's interior is thought to be composed of a rocky core, surrounded by a deep layer of metallic hydrogen, an intermediate layer of liquid hydrogen and liquid helium, and an outer layer of gas. Saturn has a pale yellow hue, due to ammonia crystals in its upper atmosphere. An electrical current in the metallic hydrogen layer is thought to give rise to Saturn's planetary magnetic field, which is weaker than Earth's, but has a magnetic moment 580 times that of Earth because of Saturn's greater size. Saturn's magnetic field strength is about a twentie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Magnetic Field
A magnetic field (sometimes called B-field) is a physical field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular to its own velocity and to the magnetic field. A permanent magnet's magnetic field pulls on ferromagnetic materials such as iron, and attracts or repels other magnets. In addition, a nonuniform magnetic field exerts minuscule forces on "nonmagnetic" materials by three other magnetic effects: paramagnetism, diamagnetism, and antiferromagnetism, although these forces are usually so small they can only be detected by laboratory equipment. Magnetic fields surround magnetized materials, electric currents, and electric fields varying in time. Since both strength and direction of a magnetic field may vary with location, it is described mathematically by a function (mathematics), function assigning a Euclidean vector, vector to each point of space, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Atmosphere Of Jupiter
The atmosphere of Jupiter is the largest planetary atmosphere in the Solar System. It is mostly made of molecular hydrogen and helium in roughly solar proportions; other chemical compounds are present only in small amounts and include methane, ammonia, hydrogen sulfide, and water. Although water is thought to reside deep in the atmosphere, its directly-measured concentration is very low. The nitrogen, sulfur, and noble gas abundances in Jupiter's atmosphere exceed solar values by a factor of about three. The atmosphere of Jupiter lacks a clear lower boundary and gradually transitions into the liquid interior of the planet. From lowest to highest, the atmospheric layers are the troposphere, stratosphere, thermosphere and exosphere. Each layer has characteristic temperature gradients. The lowest layer, the troposphere, has a complicated system of clouds and hazes composed of layers of ammonia, ammonium hydrosulfide, and water. The upper ammonia clouds visible at Jupiter's surfac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Interplanetary Medium
The interplanetary medium (IPM) or interplanetary space consists of the mass and energy which fills the Solar System, and through which all the larger Solar System bodies, such as planets, dwarf planet A dwarf planet is a small planetary-mass object that is in direct orbit around the Sun, massive enough to be hydrostatic equilibrium, gravitationally rounded, but insufficient to achieve clearing the neighbourhood, orbital dominance like the ...s, asteroids, and comets, move. The IPM stops at the Heliopause (astronomy), heliopause, outside of which the interstellar medium begins. Before 1950, interplanetary space was widely considered to either be an empty vacuum, or consisting of "Aether theories, aether". Composition and physical characteristics The interplanetary medium includes Interplanetary dust cloud, interplanetary dust, cosmic rays, and hot Plasma (physics), plasma from the solar wind. The density of the interplanetary medium is very low, decreasing in inverse pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Outer Solar System
The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar System" and "solar system" structures in theinaming guidelines document. The name is commonly rendered in lower case ('solar system'), as, for example, in the ''Oxford English Dictionary'' an''Merriam-Webster's 11th Collegiate Dictionary''. is the gravitationally bound system of the Sun and the objects that orbit it. It formed about 4.6 billion years ago when a dense region of a molecular cloud collapsed, forming the Sun and a protoplanetary disc. The Sun is a typical star that maintains a balanced equilibrium by the fusion of hydrogen into helium at its core, releasing this energy from its outer photosphere. Astronomers classify it as a G-type main-sequence star. The largest objects that orbit the Sun are the eight planets. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
