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Gould Belt
The Gould Belt is a local, partial ring of stars in the Milky Way, about 3,000 light-years long, tilted away from the galactic plane by about 16–20 degrees. It contains many O- and B-type stars, amounting to the nearest star-forming regions of the local spiral arm, to which the Sun belongs. It has recently been largely superseded in definition by the Radcliffe wave and ''Split'' linear structures. The Belt, as formed, and traditionally defined, runs for much less than one tenth of the extent of the local circumference of the galaxy, meaning in galactic coordinates it spans a narrow range of galactic longitudes. The coalescence and/or inception of new stars which cluster within it, nearby, are dated to about 30–50 million years ago. Beyond suspected prior nebulosity of many of the younger stars, and the relative concentration of gas mentioned in the Radcliffe Wave, the factors that have led to the Gould Belt's unbroken nature and concentration are far from fully u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rho Ophiuchi
Rho Ophiuchi (ρ Ophiuchi) is a multiple star system in the constellation Ophiuchus. The central system has an apparent magnitude of 4.63. Based on the central system's parallax of 9.03 mas, it is located about 360 light-years (110 parsecs) away. The other stars in the system are slightly farther away. System The central pair is known as Rho Ophiuchi AB. It consists of at least two blue-colored subgiants or main-sequence stars, designated Rho Ophiuchi A and B, respectively. Rho Ophiuchi AB is a visual binary, and the sky-projected distance between the two stars appears to be 3.1″, corresponding to a separation of at least 344 astronomical units (au). However, the actual separation is larger, and the two take about 2,400 years to complete an orbit. The two stars dominate the radiation field around the Rho Ophiuchi cloud complex. Rho Ophiuchi A emits X-rays, and exhibits strong variability in emission over periods of about 1.2 days, corresponding to its rotation per ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lacerta
Lacerta is one of the 88 modern constellations defined by the International Astronomical Union. Its name is Latin for lizard Lizards are a widespread group of squamate reptiles, with over 7,000 species, ranging across all continents except Antarctica, as well as most oceanic island chains. The group is paraphyletic since it excludes the snakes and Amphisbaenia alt .... A small, faint constellation, it was defined in 1687 by the astronomer Johannes Hevelius. Its brightest stars form a "W" shape similar to that of Cassiopeia (constellation), Cassiopeia, and it is thus sometimes referred to as 'Little Cassiopeia'. It is located between Cygnus (constellation), Cygnus, Cassiopeia and Andromeda (constellation), Andromeda on the northern celestial sphere. The northern part lies on the Milky Way. Notable features Lacerta is typical of Milky Way constellations: no bright galaxy, galaxies, nor globular clusters, but instead open clusters, for example NGC 7243, the faint planetary n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orion Nebula
The Orion Nebula (also known as Messier 42, M42, or NGC 1976) is a diffuse nebula situated in the Milky Way, being south of Orion's Belt in the constellation of Orion. It is one of the brightest nebulae and is visible to the naked eye in the night sky with apparent magnitude 4.0. It is away and is the closest region of massive star formation to Earth. The M42 nebula is estimated to be 24 light-years across (so its apparent size from Earth is approximately 1 degree). It has a mass of about 2,000 times that of the Sun. Older texts frequently refer to the Orion Nebula as the Great Nebula in Orion or the Great Orion Nebula. The Orion Nebula is one of the most scrutinized and photographed objects in the night sky and is among the most intensely studied celestial features.Press release,Astronomers Spot The Great Orion Nebula's Successor", Harvard-Smithsonian Center for Astrophysics, 2006. The nebula has revealed much about the process of how stars and planetary systems are form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stellar Kinematics
In astronomy, stellar kinematics is the observational study or measurement of the kinematics or motions of stars through space. Stellar kinematics encompasses the measurement of stellar velocities in the Milky Way and its satellites as well as the internal kinematics of more distant galaxies. Measurement of the kinematics of stars in different subcomponents of the Milky Way including the thin disk, the thick disk, the bulge, and the stellar halo provides important information about the formation and evolutionary history of our Galaxy. Kinematic measurements can also identify exotic phenomena such as hypervelocity stars escaping from the Milky Way, which are interpreted as the result of gravitational encounters of binary stars with the supermassive black hole at the Galactic Center. Stellar kinematics is related to but distinct from the subject of stellar dynamics, which involves the theoretical study or modeling of the motions of stars under the influence of gravity. Stellar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Star-forming Region
Star formation is the process by which dense regions within molecular clouds in The "medium" is present further soon.-->interstellar space, sometimes referred to as "stellar nurseries" or "-forming regions", and form s. As a branch of , star formation includes the study of the |
Orion (constellation)
Orion is a prominent constellation located on the celestial equator and visible throughout the world. It is one of the most conspicuous and recognizable constellations in the night sky. It is named after Orion (mythology), Orion, a hunter in Greek mythology. Its brightest stars are the blue-white Rigel (Beta Orionis) and the red Betelgeuse (Alpha Orionis). Characteristics Orion is bordered by Taurus to the northwest, Eridanus to the southwest, Lepus to the south, Monoceros (constellation), Monoceros to the east, and Gemini to the northeast. Covering 594 square degrees, Orion ranks twenty-sixth of the 88 constellations in size. The constellation boundaries, as set by Belgian astronomer Eugène Joseph Delporte, Eugène Delporte in 1930, are defined by a polygon of 26 sides. In the equatorial coordinate system, the right ascension coordinates of these borders lie between and , while the declination coordinates are between and . The constellation's three-letter abbreviation, as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canis Major
Canis Major is a constellation in the Southern Celestial Hemisphere, southern celestial hemisphere. In the second century, it was included in Ptolemy's 48 constellations, and is counted among the 88 modern constellations. Its name is Latin for "greater dog" in contrast to Canis Minor, the "lesser dog"; both figures are commonly represented as following the constellation of Orion (constellation), Orion the hunter through the sky. The Milky Way passes through Canis Major and several open clusters lie within its borders, most notably Messier 41, M41. Canis Major contains Sirius, the List of brightest stars, brightest star in the night sky, known as the "dog star". It is bright because of its proximity to the Solar System. In contrast, the other bright stars of the constellation are stars of great distance and high luminosity. At magnitude 1.5, Epsilon Canis Majoris (Adhara) is the second-brightest star of the constellation and the brightest source of extreme ultraviolet radiation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Puppis
Puppis is a constellation in the southern sky. Puppis, the Latin translation of "poop deck", was originally part of an over-large constellation Argo Navis (the ship of Jason and the Argonauts), which centuries after its initial description, was divided into three parts, the other two being Carina (the keel and hull), and Vela (the sails of the ship). Puppis is the largest of the three constellations in square degrees. It is one of the 88 modern constellations recognized by the International Astronomical Union. Features Argo Navis was sub-divided into three sections in 1752 by the French astronomer Nicolas Louis de Lacaille, including Argûs in puppi. Despite the division, Lacaille kept a single set of Bayer designations for the whole constellation, Argo. Therefore, Carina has the α, β, and ε, Vela has γ and δ, Puppis has ζ, and so on. In the 19th century, these three sections of Argo became established as separate constellations and were formally included in the list of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vela (constellation)
Vela is a constellation in the southern sky, which contains the Vela Supercluster. Its name is Latin for the sails of a ship, and it was originally part of a larger constellation, the ship ''Argo Navis'', which was later divided into three parts, the others being Carina (constellation), Carina and Puppis. With an apparent magnitude of 1.8, its brightest star is the hot blue multiple star Gamma Velorum, one component of which is the brightest Wolf–Rayet star, Wolf-Rayet star in the sky. Delta Velorum, Delta and Kappa Velorum, together with Epsilon Carinae, Epsilon and Iota Carinae, form the asterism (astronomy), asterism known as the False Cross. 1.95-magnitude Delta is actually a triple or quintuple star system. History Argo Navis was one of the 48 classical constellations listed by the 2nd-century astronomer Ptolemy, and represented the ship ''Argo'', used by Jason and the Argonauts on their quest for the Golden Fleece in Greek mythology. German cartographer Johann Bayer depic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carina (constellation)
Carina ( ) is a constellation in the southern sky. Its name is Latin for the keel of a ship, and it was the southern foundation of the larger constellation of Argo Navis (the ship ''Argo'') until it was divided into three pieces, the other two being Puppis (the poop deck), and Vela (the sails of the ship). History and mythology Carina was once a part of Argo Navis, the great ship of Jason and the Argonauts who searched for the Golden Fleece. The constellation of Argo was introduced in ancient Greece. However, due to the massive size of Argo Navis and the sheer number of stars that required separate designation, Nicolas-Louis de Lacaille divided Argo into three sections in 1763, including Carina (the hull or keel). In the 19th century, these three became established as separate constellations, and were formally included in the list of 88 modern IAU constellations in 1930. Lacaille kept a single set of Greek letters for the whole of Argo, and separate sets of Latin letter designa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scorpius–Centaurus Association
The Scorpius–Centaurus association (sometimes called Sco–Cen or Sco OB2) is the nearest OB association to the Sun. This stellar association is composed of three subgroups (Upper Scorpius, Upper Centaurus–Lupus, and Lower Centaurus–Crux) and its distance is about 130 parsecs or 420 light-years. Using improved Hipparcos data, Rizzuto and colleagues analysed nearby stars more closely, bringing the number of known members to 436. They doubt the need to add a subclassification because they found a more continuous spread of stars. The Sco–Cen subgroups range in age from 11 million years (Upper Scorpius) to roughly 15 million years (Upper Centaurus–Lupus and Lower Centaurus–Crux). Many of the bright stars in the constellations Scorpius, Lupus, Centaurus, and Crux are members of the Sco–Cen association, including Antares (the most massive member of Upper Scorpius), and most of the stars in the Southern Cross. Hundreds of stars have been identified as members of Sco-Cen, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crux (constellation)
Crux () is a constellation of the southern sky that is centred on four bright stars in a cross-shaped asterism commonly known as the Southern Cross. It lies on the southern end of the Milky Way's visible band. The name ''Crux'' is Latin for cross. Even though it is the smallest of all 88 modern constellations, Crux is among the most easily distinguished as its four main stars each have an apparent visual magnitude brighter than +2.8. It has attained a high level of cultural significance in many Southern Hemisphere states and nations. Blue-white α Crucis (Acrux) is the most southerly member of the constellation and, at magnitude 0.8, the brightest. The three other stars of the cross appear clockwise and in order of lessening magnitude: β Crucis (Mimosa), γ Crucis (Gacrux), and δ Crucis (Imai). ε Crucis (Ginan) also lies within the cross asterism. Many of these brighter stars are members of the Scorpius–Centaurus association, a large but loose group of hot blue-whit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
