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Flyby Anomaly
The flyby anomaly is a discrepancy between current scientific models and the actual increase in speed (i.e. increase in ''kinetic energy'') observed during a planetary flyby (usually of Earth) by a spacecraft. In multiple cases, spacecraft have been observed to gain greater speed than scientists had predicted, but thus far no convincing explanation has been found. This anomaly has been observed as shifts in the S-band and X-band Doppler and ranging telemetry. The largest discrepancy noticed during a flyby is tiny, 13.46 mm/s. Observations Gravitational assists are valuable techniques for Solar System exploration. Because the success of such flyby maneuvers depends on the exact geometry of the trajectory, the position and velocity of a spacecraft during its encounter with a planet is continually tracked with great precision by earth telemetry, e.g. via the Deep Space Network (DSN). The flyby anomaly was first noticed during a careful inspection of DSN Doppler data s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acceleration
In mechanics, acceleration is the Rate (mathematics), rate of change of the velocity of an object with respect to time. Acceleration is one of several components of kinematics, the study of motion. Accelerations are Euclidean vector, vector quantities (in that they have Magnitude (mathematics), magnitude and Direction (geometry), direction). The orientation of an object's acceleration is given by the orientation of the ''net'' force acting on that object. The magnitude of an object's acceleration, as described by Newton's second law, is the combined effect of two causes: * the net balance of all external forces acting onto that object — magnitude is Direct proportionality, directly proportional to this net resulting force; * that object's mass, depending on the materials out of which it is made — magnitude is Inverse proportionality, inversely proportional to the object's mass. The International System of Units, SI unit for acceleration is metre per second squared (, \ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goddard Space Flight Center
The Goddard Space Flight Center (GSFC) is a major NASA space research laboratory located approximately northeast of Washington, D.C., in Greenbelt, Maryland, United States. Established on May 1, 1959, as NASA's first space flight center, GSFC employs about 10,000 civil servants and contractors. Named for American rocket propulsion pioneer Robert H. Goddard, it is one of ten major NASA field centers. GSFC is partially within the former Goddard, Maryland, Goddard census-designated place; it has a Greenbelt, Maryland, Greenbelt mailing address.CENSUS 2000 BLOCK MAP: GODDARD CDP (PDF). U.S. Census Bureau. Retrieved September 1, 2018. 1990 Census map of Prince George's County [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hayabusa2
is an asteroid sample-return mission operated by the Japanese state space agency JAXA. It is a successor to the ''Hayabusa'' mission, which returned asteroid samples for the first time in June 2010. ''Hayabusa2'' was launched on 3 December 2014 and rendezvoused in space with near-Earth asteroid 162173 Ryugu on 27 June 2018. It surveyed the asteroid for a year and a half and took samples. It left the asteroid in November 2019 and returned the samples to Earth on 5 December 2020 UTC. Its mission has now been extended through at least 2031, when it will rendezvous with the small, rapidly-rotating asteroid . ''Hayabusa2'' carries multiple science payloads for remote sensing and sampling, and four small rovers to investigate the asteroid surface and analyze the environmental and geological context of the samples collected. Mission overview Asteroid 162173 Ryugu (formerly designated ) is a primitive carbonaceous near-Earth asteroid. Carbonaceous asteroids are thought to p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NEAR Shoemaker
''Near Earth Asteroid Rendezvous – Shoemaker'' (''NEAR Shoemaker''), renamed after its 1996 launch in honor of planetary scientist Eugene Merle Shoemaker, Eugene Shoemaker, was a Robotic spacecraft, robotic space probe designed by the Johns Hopkins University Applied Physics Laboratory for NASA to study the near-Earth asteroid 433 Eros, Eros from close orbit over a period of a year. It was the first spacecraft to orbit an asteroid and land on it successfully. In February 2000, the mission closed in on the asteroid and orbited it. On February 12, 2001, Shoemaker touched down on the asteroid and was terminated just over two weeks later. The primary scientific objective of ''NEAR'' was to return data on the bulk properties, composition, mineralogy, morphology, internal mass distribution, and magnetic field of Eros. Secondary objectives include studies of regolith properties, interactions with the solar wind, possible current activity as indicated by dust or gas, and the asteroi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galileo (spacecraft)
''Galileo'' was an American robotic space probe that studied the planet Jupiter and Moons of Jupiter, its moons, as well as the asteroids 951 Gaspra, Gaspra and 243 Ida, 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 Gravity assist, 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 project, ''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 main ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ʻOumuamua
Oumuamua is the first confirmed interstellar object detected passing through the Solar System. Naming of comets#Current system, Formally designated 1I/2017 U1, it was discovered by Robert Weryk using the Pan-STARRS telescope at Haleakalā Observatory, Hawaii, on 19 October 2017, approximately 40 days after it passed its Apsis#Perihelion and aphelion, closest point to the Sun on 9 September. When it was first observed, it was about 33 million km (21 million mi; 0.22 Astronomical unit, AU) from Earth (about 85 times as far away as the Moon) and already heading away from the Sun. Oumuamua is a small object estimated to be between long, with its width and thickness both estimated between . It has a red color, like objects in the outer Solar System. Despite its close approach to the Sun, it showed no signs of having a Coma (comet), coma, the usual nebula around comets formed when they pass near the Sun. Further, it exhibited Gravitational acceleration, nongravitational accelera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jupiter
Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a Jupiter mass, 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 List of brightest natural objects in the sky, 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 (god), 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Juno (spacecraft)
''Juno'' is a NASA space probe orbiting the planet Jupiter. Built by Lockheed Martin Space Systems, Lockheed Martin and operated by NASA Jet Propulsion Laboratory, the spacecraft was launched from Cape Canaveral Air Force Station on August 5, 2011 UTC, as part of the New Frontiers program. ''Juno'' entered a polar orbit of Jupiter on July 5, 2016, UTC, to begin a scientific investigation of the planet. After completing its mission, ''Juno'' was originally planned to be intentionally deorbited into Jupiter's atmosphere, but has since been approved to continue orbiting until contact is lost with the spacecraft. ''Juno'' mission is to measure Jupiter's composition, gravity field, gravitational field, magnetic field, and Magnetosphere of Jupiter, polar magnetosphere. It also searches for clues about how the planet formed, including whether it has a rocky core, the amount of water present within the deep atmosphere, mass distribution, and its deep winds, which can reach speeds up ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rosetta (spacecraft)
''Rosetta'' was a space probe built by the European Space Agency that launched on 2 March 2004. Along with ''Philae'', its lander module, ''Rosetta'' performed a detailed study of comet 67P/Churyumov–Gerasimenko (67P). During its journey to the comet, the spacecraft performed flybys of Earth, Mars, and the asteroids 21 Lutetia and 2867 Šteins. It was launched as the third cornerstone mission of the ESA's Horizon 2000 programme, after ''SOHO' Cluster'' and '' XMM-Newton''. On 6 August 2014, the spacecraft reached the comet and performed a series of manoeuvers to eventually orbit the comet at distances of . On 12 November, its lander module ''Philae'' performed the first successful landing on a comet, though its battery power ran out two days later. Communications with ''Philae'' were briefly restored in June and July 2015, but due to diminishing solar power, ''Rosetta'' communications module with the lander was turned off on 27 July 2016. On 30 September 2016, the ''Rosett ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury (planet)
Mercury is the first planet from the Sun. It is a rocky planet with a trace atmosphere. While it is the List of Solar System objects by size, smallest and least massive planet of the Solar System, its surface gravity is slightly higher than that of Mars. The surface of Mercury is similar to Earth's Moon, heavily Impact crater, cratered, with expansive rupes system, generated from thrust faults, and bright ray systems, formed by ejecta. Its largest crater, Caloris Planitia, has a diameter of , which is about one-third the diameter of the planet (). Being the most inferior planet, inferior orbiting planet it appears in Earth's sky, always close to the Sun, either as a "morning star" or an "evening star". It stays most of the time the closest to all other planets and is the planet with the highest delta-v needed to travel to from all other planets of the Solar System. Mercury's sidereal year (88.0 Earth days) and sidereal day (58.65 Earth days) are in a 3:2 ratio. This relation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MESSENGER
Messenger, Messengers, The Messenger or The Messengers may refer to: People * Courier, a person or company that delivers messages, packages, or mail * Messenger (surname) * Bicycle messenger, a bicyclist who transports packages through cities * Messenger-at-arms, an officer of the Scottish Court of Session * Messenger of the Court, a court officer responsible for carrying communications and executing other orders * Prophets and messengers in Islam * Muhammad and other prophets in Islam, who were known as Messengers of Allah (God) Science and technology Biology and chemistry * Chemical messenger, such as a hormone or neurotransmitter, a molecule used for cellular signalling * Messenger RNA (mRNA), RNA that carries information from DNA to the ribosome sites of protein synthesis in a cell Electronics and computing *Instant messenger, a tool for online text communication **Facebook Messenger, an instant messaging service by Meta (Facebook) **Microsoft Messenger service, an instant me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rosetta Space Probe
''Rosetta'' was a space probe built by the European Space Agency that launched on 2 March 2004. Along with ''Philae (spacecraft), Philae'', its lander module, ''Rosetta'' performed a detailed study of comet 67P/Churyumov–Gerasimenko (67P). During its journey to the comet, the spacecraft performed planetary flyby, flybys of Earth, Mars, and the asteroids 21 Lutetia and 2867 Šteins. It was launched as the third cornerstone mission of the ESA's Horizon 2000 programme, after ''Solar and Heliospheric Observatory, SOHO'Cluster II (spacecraft), Cluster'' and ''XMM-Newton''. On 6 August 2014, the spacecraft reached the comet and performed a series of manoeuvers to eventually orbit the comet at distances of . On 12 November, its lander module ''Philae'' performed the first successful landing on a comet, though its battery power ran out two days later. Communications with ''Philae'' were briefly restored in June and July 2015, but due to diminishing solar power, ''Rosetta'' communicat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
