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Solar Eclipses On Jupiter
Solar eclipses on Jupiter occur when any of the natural satellites of Jupiter pass in front of the Sun as seen from the planet Jupiter. For bodies which appear smaller in angular diameter than the Sun, the proper term would be a transit. For bodies which are larger than the apparent size of the Sun, the proper term would be an occultation. There are five satellites capable of completely occulting the Sun: Amalthea, Io, Europa, Ganymede and Callisto. All of the others are too small or too distant to be able to completely occult the Sun, so can only transit the Sun. Most of the more distant satellites also have orbits that are strongly inclined to the plane of Jupiter's orbit, and would rarely be seen to transit. When the four largest satellites of Jupiter, the Galilean satellites, occult the Sun, a ''shadow transit'' can be seen on the surface of Jupiter which can be observed from Earth in telescopes. Eclipses of the Sun from Jupiter are not particularly rare, since Jupi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giovanni Cassini
Giovanni Domenico Cassini, also known as Jean-Dominique Cassini (8 June 1625 – 14 September 1712) was an Italian (naturalised French) mathematician, astronomer and engineer. Cassini was born in Perinaldo, near Imperia, at that time in the County of Nice, part of the Savoyard state. Cassini is known for his work on astronomy and engineering. He discovered four satellites of the planet Saturn (planet), Saturn and noted the division of the rings of Saturn; the Cassini Division was named after him. Giovanni Domenico Cassini was also the first of his family to begin work on the project of creating a topographic map of France. The Cassini–Huygens, ''Cassini'' space probe, launched in 1997, was named after him and became the fourth to visit the planet Saturn and the first to orbit the planet. Life Time in Italy Cassini was the son of Jacopo Cassini, a Tuscan, and Giulia Crovesi. In 1648 Cassini accepted a position at the observatory at Panzano, near Bologna, to work with Marqui ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minute And Second Of Arc
A minute of arc, arcminute (arcmin), arc minute, or minute arc, denoted by the symbol , is a unit of angular measurement equal to of one degree. Since one degree is of a turn (or complete rotation), one minute of arc is of a turn. The nautical mile (nmi) was originally defined as the arc length of a minute of latitude on a spherical Earth, so the actual Earth circumference is very near . A minute of arc is of a radian. A second of arc, arcsecond (arcsec), or arc second, denoted by the symbol , is of an arcminute, of a degree, of a turn, and (about ) of a radian. These units originated in Babylonian astronomy as sexagesimal subdivisions of the degree; they are used in fields that involve very small angles, such as astronomy, optometry, ophthalmology, optics, navigation, land surveying, and marksmanship. To express even smaller angles, standard SI prefixes can be employed; the milliarcsecond (mas) and microarcsecond (μas), for instance, are commonly used in astr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mean
There are several kinds of mean in mathematics, especially in statistics. Each mean serves to summarize a given group of data, often to better understand the overall value (magnitude and sign) of a given data set. For a data set, the ''arithmetic mean'', also known as "arithmetic average", is a measure of central tendency of a finite set of numbers: specifically, the sum of the values divided by the number of values. The arithmetic mean of a set of numbers ''x''1, ''x''2, ..., x''n'' is typically denoted using an overhead bar, \bar. If the data set were based on a series of observations obtained by sampling from a statistical population, the arithmetic mean is the ''sample mean'' (\bar) to distinguish it from the mean, or expected value, of the underlying distribution, the ''population mean'' (denoted \mu or \mu_x).Underhill, L.G.; Bradfield d. (1998) ''Introstat'', Juta and Company Ltd.p. 181/ref> Outside probability and statistics, a wide range of other notions of mean are o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Juno (spacecraft)
''Juno'' is a NASA space probe orbiting the planet Jupiter. It was built by Lockheed Martin and is 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'' will be intentionally deorbited into Jupiter's atmosphere. ''Juno'' mission is to measure Jupiter's composition, gravitational field, magnetic field, and polar magnetosphere. It will also search 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 to . ''Juno'' is the second spacecraft to orbit Jupiter, after the nuclear powered ''Galileo'' orbiter, which orbited from 1995 to 2003. Unlike all earlier spacecr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Horizons
''New Horizons'' is an Interplanetary spaceflight, interplanetary space probe that was launched as a part of NASA's New Frontiers program. Engineered by the Johns Hopkins University Applied Physics Laboratory (APL) and the Southwest Research Institute (SwRI), with a team led by Alan Stern, the spacecraft was launched in 2006 with the primary mission to perform a Planetary flyby, flyby study of the Pluto system in 2015, and a secondary mission to fly by and study one or more other Kuiper belt objects (KBOs) in the decade to follow, which became a mission to 486958 Arrokoth. It is the List of artificial objects leaving the Solar System, fifth space probe to achieve the escape velocity needed to leave the Solar System. On January 19, 2006, ''New Horizons'' was launched from Cape Canaveral Space Force Station by an Atlas V rocket directly into an Earth-and-solar Escape velocity, escape trajectory with a speed of about . It was the fastest (average speed with respect to Earth) man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cassini–Huygens
''Cassini–Huygens'' ( ), commonly called ''Cassini'', was a space research, space-research mission by NASA, the European Space Agency (ESA), and the Italian Space Agency (ASI) to send a space probe to study the planet Saturn and its system, including its Rings of Saturn, rings and Moons of Saturn, natural satellites. The Large Strategic Science Missions, Flagship-class robotic spacecraft comprised both NASA's ''Cassini'' space probe and ESA's Huygens (spacecraft), ''Huygens'' lander (spacecraft), lander, which landed on Saturn's largest moon, Titan (moon), Titan. ''Cassini'' was the fourth space probe to visit Saturn and the first to enter its orbit, where it stayed from 2004 to 2017. The two craft took their names from the astronomers Giovanni Domenico Cassini, Giovanni Cassini and Christiaan Huygens. Launched aboard a Titan IV, Titan IVB/Centaur on October 15, 1997, ''Cassini'' was active in space for nearly 20 years, with 13 years spent orbiting Saturn and studying the pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galileo (spacecraft)
''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 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] |
Voyager 2
''Voyager 2'' is a space probe launched by NASA on August 20, 1977, to study the outer planets and interstellar space beyond the Sun's heliosphere. As a part of the Voyager program, it was launched 16 days before its twin, ''Voyager 1'', on a trajectory that took longer to reach gas giants Jupiter and Saturn but enabled further encounters with ice giants Uranus and Neptune. ''Voyager 2'' remains the only spacecraft to have visited either of the ice giant planets. ''Voyager 2'' was the fourth of five spacecraft to achieve Solar escape velocity, which allowed it to leave the Solar System. ''Voyager 2'' successfully fulfilled its primary mission of visiting the Jovian system in 1979, the Saturnian system in 1981, Uranian system in 1986, and the Neptunian system in 1989. The spacecraft is now in its extended mission of studying interstellar space. It has been operating for as of ; , it has reached a distance of from Earth. The probe entered interstellar space on November 5, 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
