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DU Crucis
DU Crucis is a red supergiant and slow irregular variable star in the open cluster NGC 4755, which is also known as the Kappa (κ) Crucis Cluster or Jewel Box Cluster. Location DU Crucis is one of the brighter members of the Jewel Box Cluster and the brightest red supergiant, strongly contrasting with the other bright members which are blue supergiants. It is part of the central bar of the prominent letter "A"-shaped asterism at the centre of the cluster. The cluster is part of the larger Centaurus OB1 association and lies about 8,500 light years away. The cluster is just to the south-east of β Crucis, the lefthand star of the Southern Cross. Properties DU Crucis is an M2 intermediate luminosity supergiant Supergiants are among the most massive and most luminous stars. Supergiant stars occupy the top region of the Hertzsprung–Russell diagram with absolute visual magnitudes between about −3 and −8. The temperature range of supergiant stars spa ... (luminosity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
A Hubble Gem - The Jewel Box
A, or a, is the first Letter (alphabet), letter and the first vowel of the Latin alphabet, Latin alphabet, used in the English alphabet, modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is English alphabet#Letter names, ''a'' (pronounced ), plural English alphabet#Letter names, ''aes''. It is similar in shape to the Greek alphabet#History, Ancient Greek letter alpha, from which it derives. The Letter case, uppercase version consists of the two slanting sides of a triangle, crossed in the middle by a horizontal bar. The lowercase version can be written in two forms: the double-storey a and single-storey ɑ. The latter is commonly used in handwriting and fonts based on it, especially fonts intended to be read by children, and is also found in italic type. In English grammar, "English articles, a", and its variant "English articles#Indefinite article, an", are Article (grammar)#Indefinite article, indefinite arti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blue Supergiant
A blue supergiant (BSG) is a hot, luminous star, often referred to as an OB supergiant. They have luminosity class I and spectral class B9 or earlier. Blue supergiants are found towards the top left of the Hertzsprung–Russell diagram, above and to the right of the main sequence. They are larger than the Sun but smaller than a red supergiant, with surface temperatures of 10,000–50,000 K and luminosities from about 10,000 to a million times that of the Sun. Formation Supergiants are evolved high-mass stars, larger and more luminous than main-sequence stars. O class and early B class stars with initial masses around evolve away from the main sequence in just a few million years as their hydrogen is consumed and heavy elements start to appear near the surface of the star. These stars usually become blue supergiants, although it is possible that some of them evolve directly to Wolf–Rayet stars. Expansion into the supergiant stage occurs when hydrogen in the core of the sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slow Irregular Variables
In everyday use and in kinematics, the speed (commonly referred to as ''v'') of an object is the magnitude of the change of its position over time or the magnitude of the change of its position per unit of time; it is thus a scalar quantity. The average speed of an object in an interval of time is the distance travelled by the object divided by the duration of the interval; the instantaneous speed is the limit of the average speed as the duration of the time interval approaches zero. Speed is not the same as velocity. Speed has the dimensions of distance divided by time. The SI unit of speed is the metre per second (m/s), but the most common unit of speed in everyday usage is the kilometre per hour (km/h) or, in the US and the UK, miles per hour (mph). For air and marine travel, the knot is commonly used. The fastest possible speed at which energy or information can travel, according to special relativity, is the speed of light in a vacuum ''c'' = metres per second (approx ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2MASS Objects
Mass is an intrinsic property of a body. It was traditionally believed to be related to the quantity of matter in a physical body, until the discovery of the atom and particle physics. It was found that different atoms and different elementary particles, theoretically with the same amount of matter, have nonetheless different masses. Mass in modern physics has multiple definitions which are conceptually distinct, but physically equivalent. Mass can be experimentally defined as a measure of the body's inertia, meaning the resistance to acceleration (change of velocity) when a net force is applied. The object's mass also determines the strength of its gravitational attraction to other bodies. The SI base unit of mass is the kilogram (kg). In physics, mass is not the same as weight, even though mass is often determined by measuring the object's weight using a spring scale, rather than balance scale comparing it directly with known masses. An object on the Moon would weigh less t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Durchmusterung Objects
In astronomy, Durchmusterung or Bonner Durchmusterung (BD) is an astrometric star catalogue of the whole sky, compiled by the Bonn Observatory in Germany from 1859 to 1903. The name comes from ('run-through examination'), a German word used for a systematic survey of objects or data. The term has sometimes been used for other astronomical surveys, including not only stars, but also the search for other celestial objects. Special tasks include celestial scanning in electromagnetic wavelengths shorter or longer than visible light waves. Original catalog The 44 years of work on the Bonner Durchmusterung (abbreviated BD), initiated by Friedrich Argelander and largely carried out by his assistants, resulted in a catalogue of the positions and apparent magnitudes of approximately 325,000 stars to apparent magnitude 9–10. The catalogue was accompanied by charts plotting the positions of the stars, and was the basis for the ''Astronomische Gesellschaft Katalog'' (AGK) and ''Smithsonia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hipparcos Objects
''Hipparcos'' was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993. It was the first space experiment devoted to precision astrometry, the accurate measurement of the positions of celestial objects on the sky. This permitted the first high-precision measurements of the intrinsic brightnesses (compared to the less precise apparent brightness), proper motions, and parallaxes of stars, enabling better calculations of their distance and tangential velocity. When combined with radial velocity measurements from spectroscopy, astrophysicists were able to finally measure all six quantities needed to determine the motion of stars. The resulting ''Hipparcos Catalogue'', a high-precision catalogue of more than 118,200 stars, was published in 1997. The lower-precision ''Tycho Catalogue'' of more than a million stars was published at the same time, while the enhanced Tycho-2 Catalogue of 2.5 million stars was published in 2000. ''Hipparcos'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
M-type Supergiants
Type M or M type may refer to: Science and technology * Type M, a xD-Picture Card * Type M, a name for the 15 amp BS 546 electrical plug * Vaio Type M, a kind of Vaio computer from Sony * M-type asteroid * m-type filter, an electronic filter * M-type star * M-types, an implementation of inductive type Other uses * Audi Type M, a 1920s car * Beretta 92FS Compact Type M, a pistol * MG M-type, a sports car See also * M class (other) M class or M-class may refer to: Military * M-class cruiser, a planned German light cruiser class * M-class destroyer, several classes of destroyer ** Admiralty M-class destroyer, a class of British destroyers built 1913–1916 and served in World ... * Class M (other) {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hipparcos
''Hipparcos'' was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993. It was the first space experiment devoted to precision astrometry, the accurate measurement of the positions of celestial objects on the sky. This permitted the first high-precision measurements of the intrinsic brightnesses (compared to the less precise apparent brightness), proper motions, and parallaxes of stars, enabling better calculations of their distance and tangential velocity. When combined with radial velocity measurements from spectroscopy, astrophysicists were able to finally measure all six quantities needed to determine the motion of stars. The resulting ''Hipparcos Catalogue'', a high-precision catalogue of more than 118,200 stars, was published in 1997. The lower-precision ''Tycho Catalogue'' of more than a million stars was published at the same time, while the enhanced Tycho-2 Catalogue of 2.5 million stars was published in 2000. ''Hipparcos' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supergiant
Supergiants are among the most massive and most luminous stars. Supergiant stars occupy the top region of the Hertzsprung–Russell diagram with absolute visual magnitudes between about −3 and −8. The temperature range of supergiant stars spans from about 3,400 K to over 20,000 K. Definition The title supergiant, as applied to a star, does not have a single concrete definition. The term ''giant star'' was first coined by Hertzsprung when it became apparent that the majority of stars fell into two distinct regions of the Hertzsprung–Russell diagram. One region contained larger and more luminous stars of spectral types A to M and received the name ''giant''. Subsequently, as they lacked any measurable parallax, it became apparent that some of these stars were significantly larger and more luminous than the bulk, and the term ''super-giant'' arose, quickly adopted as ''supergiant''. Spectral luminosity class Supergiant stars can be identified on the basis of thei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southern Cross
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] |
Beta Crucis
Mimosa is the second-brightest object in the southern constellation of Crux (after Acrux), and the 20th-brightest star in the night sky. It has the Bayer designation β Crucis, which is Latinised to Beta Crucis and abbreviated Beta Cru or β Cru. Mimosa forms part of the prominent asterism called the Southern Cross. It is a binary star or a possible triple star system. Nomenclature ''β Crucis'' (Latinised to ''Beta Crucis'') is the system's Bayer designation. Although Mimosa is at roughly −60° declination, and therefore not visible north of 30° latitude, in the time of the ancient Greeks and Romans it was visible north of 40° due to the precession of equinoxes, and these civilizations regarded it as part of the constellation of Centaurus. It bore the traditional names ''Mimosa'' and the historical name ''Becrux'' . ''Mimosa'', which is derived from the Latin for 'actor', may come from the flower of the same name. ''Becrux'' is a modern contraction of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
