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9 Metis
9 Metis is one of the larger main-belt asteroids. It is composed of silicates and metallic nickel-iron, and may be the core remnant of a large asteroid that was destroyed by an ancient collision. Metis is estimated to contain just under half a percent of the total mass of the asteroid belt. Discovery and naming Metis was discovered by Andrew Graham on 25 April 1848, at Markree Observatory in Ireland; it was his only asteroid discovery. It also has been the only asteroid to have been discovered as a result of observations from Ireland until 7 October 2008, when, 160 years later, Dave McDonald from observatory J65 discovered (281507) 2008 TM9. Its name comes from the mythological Metis, a Titaness and Oceanid, daughter of Tethys and Oceanus. The name ''Thetis'' was also considered and rejected (it would later devolve to 17 Thetis). The historical symbol for Metis was an eye with a star above it. It is in the pipeline for Unicode 17.0 as U+1CEC3 𜻃 (). Characteristic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Metis (moon)
Metis , also known as , is the innermost known moon of Jupiter. It was discovered in 1979 in images taken by ''Voyager 1'', and was named in 1983 after the Titaness Metis, the first wife of Zeus and the mother of Athena. Additional observations made between early 1996 and September 2003 by the ''Galileo'' spacecraft allowed its surface to be imaged. Metis is tidally locked to Jupiter, and its shape is strongly asymmetrical, with the largest diameter being almost twice as large as the smallest one. It is also one of the two moons known to orbit Jupiter in less than the length of Jupiter's day, the other being Adrastea. It orbits within the main ring of Jupiter, and is thought to be a major contributor of ring material. Discovery and observations Metis was discovered in 1979 by Stephen P. Synnott in images taken by the ''Voyager 1'' probe and was provisionally designated as . In 1983, it was officially named after the mythological Metis, a Titaness who was the first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Oceanid
In Greek mythology, the Oceanids or Oceanides ( ; , ) are the nymphs who were the three thousand (a number interpreted as meaning "innumerable") daughters of the Titans Oceanus and Tethys. Description and function The Oceanids' father Oceanus was the great primordial world-encircling river, their mother Tethys was a sea goddess, and their brothers the river gods (also three thousand in number) were the personifications of the great rivers of the world. Like the rest of their family, the Oceanid nymphs were associated with water, as the personification of springs. Hesiod says they are "dispersed far and wide" and everywhere "serve the earth and the deep waters", while in Apollonius of Rhodes' ''Argonautica'', the Argonauts, stranded in the desert of Libya, beg the "nymphs, sacred of the race of Oceanus" to show them "some spring of water from the rock or some sacred flow gushing from the earth". The Oceanids are not easily categorized, nor confined to any single function, no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Iron
Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's outer and inner core. It is the fourth most abundant element in the Earth's crust, being mainly deposited by meteorites in its metallic state. Extracting usable metal from iron ores requires kilns or furnaces capable of reaching , about 500 °C (900 °F) higher than that required to smelt copper. Humans started to master that process in Eurasia during the 2nd millennium BC and the use of iron tools and weapons began to displace copper alloys – in some regions, only around 1200 BC. That event is considered the transition from the Bronze Age to the Iron Age. In the modern world, iron alloys, such as steel, stainless steel, cast iron and special steels, are by far the most common industrial metals, due to their mechan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Nickel
Nickel is a chemical element; it has symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel is a hard and ductile transition metal. Pure nickel is chemically reactive, but large pieces are slow to react with air under standard conditions because a passivation layer of nickel oxide forms on the surface that prevents further corrosion. Even so, pure native nickel is found in Earth's crust only in tiny amounts, usually in ultramafic rocks, and in the interiors of larger nickel–iron meteorites that were not exposed to oxygen when outside Earth's atmosphere. Meteoric nickel is found in combination with iron, a reflection of the origin of those elements as major end products of supernova nucleosynthesis. An iron–nickel mixture is thought to compose Earth's outer and inner cores. Use of nickel (as natural meteoric nickel–iron alloy) has been traced as far back as 3500 BCE. Nickel was first isolated and classifie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Olivine
The mineral olivine () is a magnesium iron Silicate minerals, silicate with the chemical formula . It is a type of Nesosilicates, nesosilicate or orthosilicate. The primary component of the Earth's upper mantle (Earth), upper mantle, it is a common mineral in Earth's subsurface, but weathers quickly on the surface. Olivine has many uses, such as the gemstone peridot (or chrysolite), as well as industrial applications like metalworking processes. The ratio of magnesium to iron varies between the two endmember (mineralogy), endmembers of the solid solution series: forsterite (Mg-endmember: ) and fayalite (Fe-endmember: ). Compositions of olivine are commonly expressed as Mole (unit), molar percentages of forsterite (Fo) and/or fayalite (Fa) (''e.g.'', Fo70Fa30, or just Fo70 with Fa30 implied). Forsterite's melting temperature is unusually high at atmospheric pressure, almost , while fayalite's is much lower – about . Melting temperature varies smoothly between the two end ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Hubble Space Telescope
The Hubble Space Telescope (HST or Hubble) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the Orbiting Solar Observatory, first space telescope, but it is one of the largest and most versatile, renowned as a vital research tool and as a public relations boon for astronomy. The Hubble Space Telescope is named after astronomer Edwin Hubble and is one of NASA's Great Observatories program, Great Observatories. The Space Telescope Science Institute (STScI) selects Hubble's targets and processes the resulting data, while the Goddard Space Flight Center (GSFC) controls the spacecraft. Hubble features a mirror, and its five main instruments observe in the ultraviolet, visible spectrum, visible, and near-infrared regions of the electromagnetic spectrum. Hubble's orbit outside the distortion of atmosphere of Earth, Earth's atmosphere allows it to capture extremely high-resolution images with substantially lower background lig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Axial Tilt
In astronomy, axial tilt, also known as obliquity, is the angle between an object's rotational axis and its orbital axis, which is the line perpendicular to its orbital plane; equivalently, it is the angle between its equatorial plane and orbital plane. It differs from orbital inclination. At an obliquity of 0 degrees, the two axes point in the same direction; that is, the rotational axis is perpendicular to the orbital plane. The rotational axis of Earth, for example, is the imaginary line that passes through both the North Pole and South Pole, whereas the Earth's orbital axis is the line perpendicular to the imaginary plane through which the Earth moves as it revolves around the Sun; the Earth's obliquity or axial tilt is the angle between these two lines. Over the course of an orbital period, the obliquity usually does not change considerably, and the orientation of the axis remains the same relative to the background of stars. This causes one pole to be pointed mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Equatorial Coordinate System
The equatorial coordinate system is a celestial coordinate system widely used to specify the positions of astronomical object, celestial objects. It may be implemented in spherical coordinate system, spherical or Cartesian coordinate system, rectangular coordinates, both defined by an origin (mathematics), origin at the centre of Earth, a fundamental plane (spherical coordinates), fundamental plane consisting of the projective geometry, projection of Earth's equator onto the celestial sphere (forming the celestial equator), a primary direction towards the March equinox, March equinox (celestial coordinates), equinox, and a right-hand rule, right-handed convention. The origin at the centre of Earth means the coordinates are ''geocentric model, geocentric'', that is, as seen from the centre of Earth as if it were transparency and translucency, transparent. The fundamental plane and the primary direction mean that the coordinate system, while aligned with Earth's equator and geograp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Ecliptic Coordinate System
In astronomy, the ecliptic coordinate system is a celestial coordinate system commonly used for representing the apparent positions, orbits, and pole orientations of Solar System objects. Because most planets (except Mercury) and many small Solar System bodies have orbits with only slight inclinations to the ecliptic, using it as the fundamental plane is convenient. The system's origin can be the center of either the Sun or Earth, its primary direction is towards the March equinox, and it has a right-hand convention. It may be implemented in spherical or rectangular coordinates. Primary direction The celestial equator and the ecliptic are slowly moving due to perturbing forces on the Earth, therefore the orientation of the primary direction, their intersection at the March equinox, is not quite fixed. A slow motion of Earth's axis, precession, causes a slow, continuous turning of the coordinate system westward about the poles of the ecliptic, completing one circ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Metis Symbol (fixed Width)
Metis or Métis, meaning "mixed" in French, may refer to: Ethnic groups * Métis, recognized Indigenous communities in Canada and the United States whose distinct culture and language emerged after early intermarriage between First Nations peoples and early European settlers, primarily French fur trappers * Métis (Belgian Congo), mixed-race children born in the Congo during Belgian colonial rule Places * Grand-Métis, Quebec, Canada * Métis-sur-Mer, Quebec, Canada * Saint-Paul-des-Métis, now St. Paul, Alberta, Canada * Metis Shoal, the tip of a submarine volcano in Tonga * Metiş, a village in Mihăileni, Sibiu, Romania * Metis Island in Antarctica Other uses * 9 Metis, an asteroid * 9K115 Metis, a Russian anti–tank missile system * 9K115-2 Metis-M, a Russian anti–tank missile system * Metis (American musician) (fl. 21st century), American rapper * Metis (theorem prover), an automated theorem prover * Metis (Japanese musician) (born 1984), Japanese reggae singer * M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Unicode
Unicode or ''The Unicode Standard'' or TUS is a character encoding standard maintained by the Unicode Consortium designed to support the use of text in all of the world's writing systems that can be digitized. Version 16.0 defines 154,998 Character (computing), characters and 168 script (Unicode), scripts used in various ordinary, literary, academic, and technical contexts. Unicode has largely supplanted the previous environment of a myriad of incompatible character sets used within different locales and on different computer architectures. The entire repertoire of these sets, plus many additional characters, were merged into the single Unicode set. Unicode is used to encode the vast majority of text on the Internet, including most web pages, and relevant Unicode support has become a common consideration in contemporary software development. Unicode is ultimately capable of encoding more than 1.1 million characters. The Unicode character repertoire is synchronized with Univers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
