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Corona Australis Molecular Cloud
Corona Australis is a constellation in the Southern Celestial Hemisphere. Its Latin name means "southern crown", and it is the southern counterpart of Corona Borealis, the northern crown. It is one of the 48 constellations listed by the 2nd-century astronomer Ptolemy, and it remains one of the 88 modern constellations. The Ancient Greeks saw Corona Australis as a wreath rather than a crown and associated it with Sagittarius (constellation), Sagittarius or Centaurus. Other cultures have likened the pattern to a turtle, ostrich nest, a tent, or even a hut belonging to a rock hyrax. Although fainter than its northern counterpart, the oval- or horseshoe-shaped pattern of its brighter stars renders it distinctive. Alpha Coronae Australis, Alpha and Beta Coronae Australis are the two brightest stars with an apparent magnitude of around 4.1. Epsilon Coronae Australis is the brightest example of a W Ursae Majoris variable in the southern sky. Lying alongside the Milky Way, Corona Australi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South
South is one of the cardinal directions or compass points. The direction is the opposite of north and is perpendicular to both west and east. Etymology The word ''south'' comes from Old English ''sūþ'', from earlier Proto-Germanic ''*sunþaz'' ("south"), possibly related to the same Proto-Indo-European root that the word ''sun'' derived from. Some languages describe south in the same way, from the fact that it is the direction of the sun at noon (in the Northern Hemisphere), like Latin meridies 'noon, south' (from medius 'middle' + dies 'day', ), while others describe south as the right-hand side of the rising sun, like Biblical Hebrew תֵּימָן teiman 'south' from יָמִין yamin 'right', Aramaic תַּימנַא taymna from יָמִין yamin 'right' and Syriac ܬܰܝܡܢܳܐ taymna from ܝܰܡܝܺܢܳܐ yamina (hence the name of Yemen, the land to the south/right of the Levant). South is sometimes abbreviated as S. Navigation By convention, the ''bottom or down ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rock Hyrax
The rock hyrax (; ''Procavia capensis''), also called dassie, Cape hyrax, rock rabbit, and (from some interpretations of a word used in the King James Bible) coney, is a medium-sized terrestrial mammal native to Africa and the Middle East. Commonly referred to in South Africa as the dassie (; ), it is one of the five living species of the order Hyracoidea, and the only one in the genus ''Procavia''. Rock hyraxes weigh and have short ears. Rock hyraxes are found at elevations up to above sea level in habitats with rock crevices, allowing them to escape from predators. They are the only extant terrestrial afrotherians in the Middle East. Hyraxes typically live in groups of 10–80 animals, and forage as a group. They have been reported to use sentries to warn of the approach of predators. Having incomplete thermoregulation, they are most active in the morning and evening, although their activity pattern varies substantially with season and climate. Over most of its range, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Eugène Joseph Delporte
Eugène Joseph Delporte (10 January 1882 – 19 October 1955) was a Belgian astronomer born in Genappe. He discovered a total of sixty-six asteroids. Notable discoveries include 1221 Amor (which lent its name to the Amor asteroids) and the Apollo asteroid 2101 Adonis. He discovered or co-discovered some comets as well, including periodic comet 57P/du Toit-Neujmin-Delporte. He worked in the Observatoire Royal de Belgique (Belgian Royal Observatory), situated in the town of Uccle (after which the asteroid 1276 Ucclia is named). He started there in 1903 after receiving his doctorate that year from the Free University of Brussels. In 1930, he drew the modern boundaries between all of the constellations in the sky, along lines of right ascension and declination In astronomy, declination (abbreviated dec; symbol ''δ'') is one of the two angles that locate a point on the celestial sphere in the equatorial coordinate system, the other being hour angle. The declination ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Astronomical Union
The International Astronomical Union (IAU; , UAI) is an international non-governmental organization (INGO) with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach, education, and development through global cooperation. It was founded on 28 July 1919 in Brussels, Belgium and is based in Paris, France. The IAU is composed of individual members, who include both professional astronomers and junior scientists, and national members, such as professional associations, national societies, or academic institutions. Individual members are organised into divisions, committees, and working groups centered on particular subdisciplines, subjects, or initiatives. the Union had 85 national members and 12,734 individual members, spanning 90 countries and territories. Among the key activities of the IAU is serving as a forum for scientific conferences. It sponsors nine annual symposia and holds a triannual General Assembly that sets policy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TY Coronae Australis
TY Coronae Australis (abbreviated as TY CrA), is a young star system around 3 million years old in the constellation Corona Australis. It is composed of a blue-white B-class star around triple the Sun's mass and a cooler smaller companion around half its mass (or 1.6 times that of the Sun). The system is an eclipsing binary with a period of 2.8 days. Robert T. A. Innes announced his discovery that the star is a variable star A variable star is a star whose brightness as seen from Earth (its apparent magnitude) changes systematically with time. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are ..., in 1916. References Corona Australis Herbig Ae/Be stars Eclipsing binaries Durchmusterung objects Coronae Australis, TY {{var-star-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
R Coronae Australis
R Coronae Australis (R CrA) is a variable binary system in the constellation Corona Australis. It has varied between magnitudes 10 and 14.36. A small reflection/ emission nebula NGC 6729 extends from the star towards SE. It is also the brightest feature of the Coronet Cluster, therefore sometimes called R CrA Cluster. This star is moving toward the Solar System with a radial velocity of . It was previously believed that in roughly 222,000 years, this system could have approached within of the Sun. However, the estimate had a considerable margin of error in it. With the release of Gaia DR2, the star was determined to be 4 times further from the Sun than initially believed, constraining the approach to only . Examination of other objects known to be in the same star-forming region gives a distance of , suggesting an error in the Gaia parallax for R CrA itself. Johann Friedrich Julius Schmidt discovered that R Coronae Australis is a variable star, in 1865. It app ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corona Australis Molecular Cloud
Corona Australis is a constellation in the Southern Celestial Hemisphere. Its Latin name means "southern crown", and it is the southern counterpart of Corona Borealis, the northern crown. It is one of the 48 constellations listed by the 2nd-century astronomer Ptolemy, and it remains one of the 88 modern constellations. The Ancient Greeks saw Corona Australis as a wreath rather than a crown and associated it with Sagittarius (constellation), Sagittarius or Centaurus. Other cultures have likened the pattern to a turtle, ostrich nest, a tent, or even a hut belonging to a rock hyrax. Although fainter than its northern counterpart, the oval- or horseshoe-shaped pattern of its brighter stars renders it distinctive. Alpha Coronae Australis, Alpha and Beta Coronae Australis are the two brightest stars with an apparent magnitude of around 4.1. Epsilon Coronae Australis is the brightest example of a W Ursae Majoris variable in the southern sky. Lying alongside the Milky Way, Corona Australi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dark Nebula
A dark nebula or absorption nebula is a type of interstellar cloud, particularly molecular clouds, that is so dense that it obscures the visible wavelengths of light from objects behind it, such as background stars and emission or reflection nebulae. The extinction of the light is caused by interstellar dust grains in the coldest, densest parts of molecular clouds. Clusters and large complexes of dark nebulae are associated with Giant Molecular Clouds. Isolated small dark nebulae are called Bok globules. Like other interstellar dust or material, the things it obscures are visible only using radio waves in radio astronomy or infrared in infrared astronomy. Dark clouds appear so because of sub-micrometre-sized dust particles, coated with frozen carbon monoxide and nitrogen, which effectively block the passage of light at visible wavelengths. Also present are molecular hydrogen, atomic helium, C18O (CO with oxygen as the 18O isotope), CS, NH3 (ammonia), H2CO (formaldehyde), c- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 Planetary system, system of the Sun and the objects that orbit it. It Formation and evolution of the Solar System, 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 hydrostatic equilibrium, balanced equilibrium by the thermonuclear fusion, fusion of hydrogen into helium at its stellar core, core, releasing this energy from its outer photosphere. As ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Star Formation
Star formation is the process by which dense regions within molecular clouds in interstellar space—sometimes referred to as "stellar nurseries" or "star-forming regions"—Jeans instability, collapse and form stars. As a branch of astronomy, star formation includes the study of the interstellar medium (ISM) and giant molecular clouds (GMC) as precursors to the star formation process, and the study of protostars and young stellar objects as its immediate products. It is closely related to planet formation, another branch of astronomy. Star formation theory, as well as accounting for the formation of a single star, must also account for the statistics of binary stars and the initial mass function. Most stars do not form in isolation but as part of a group of stars referred as star clusters or stellar associations. First stars Star formation is divided into three groups called "Populations". Population III stars formed from primordial hydrogen after the Big Bang. These stars are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Milky Way
The Milky Way or Milky Way Galaxy is the galaxy that includes the Solar System, with the name describing the #Appearance, galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars in other arms of the galaxy, which are so far away that they cannot be individually distinguished by the naked eye. The Milky Way is a barred spiral galaxy with a Galaxy#Isophotal diameter, D25 isophotal diameter estimated at , but only about 1,000 light-years thick at the spiral arms (more at the bulge). Recent simulations suggest that a dark matter area, also containing some visible stars, may extend up to a diameter of almost 2 million light-years (613 kpc). The Milky Way has several List of Milky Way's satellite galaxies, satellite galaxies and is part of the Local Group of galaxies, forming part of the Virgo Supercluster which is itself a component of the Laniakea Supercluster. It is estimated to contain 100–400 billion stars and at least that number of pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
