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Epsilon Crucis
Epsilon Crucis, ε Crucis (abbreviated Eps Cru, ε Cru), also known as Ginan , is a single, orange-hued star in the southern constellation of Crux. Measurements made by the Hipparcos spacecraft showed an annual parallax shift of 14.19 mas, which provides a distance estimate of about 230 light years. The star can be seen with the naked eye, having an apparent visual magnitude of 3.58. It is moving closer to the Sun with a radial velocity of −4.60 km.s−1. This is a giant star of type K with a stellar classification of K3III, indicating that it has exhausted the hydrogen at its core and evolved away from the main sequence. It is about two billion years old with 1.5 times the mass of the Sun and has expanded to 28 times the Sun's radius. The star is shining with around 302 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,294 K. Nomenclature ε Crucis ( Latinised to ''Epsilon Crucis'') is the star's B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
J2000
In astronomy, an epoch or reference epoch is a instant, moment in time used as a reference point for some time-varying astronomical quantity. It is useful for the celestial coordinates or orbital elements of a Astronomical object, celestial body, as they are subject to Perturbation (astronomy), perturbations and vary with time. These time-varying astronomical quantities might include, for example, the mean longitude or mean anomaly of a body, the node of its orbit relative to a reference plane, the direction of the apogee or Perihelion and aphelion, aphelion of its orbit, or the size of the major axis of its orbit. The main use of astronomical quantities specified in this way is to calculate other relevant parameters of motion, in order to predict future positions and velocities. The applied tools of the disciplines of celestial mechanics or its subfield orbital mechanics (for predicting orbital paths and positions for bodies in motion under the gravitational effects of other bodi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mass Of The Sun
The solar mass () is a standard unit of mass in astronomy, equal to approximately . It is often used to indicate the masses of other stars, as well as stellar clusters, nebulae, galaxies and black holes. It is approximately equal to the mass of the Sun. This equates to about two nonillion (short scale), two quintillion (long scale) kilograms or 2000 quettagrams: The solar mass is about times the mass of Earth (), or times the mass of Jupiter (). History of measurement The value of the gravitational constant was first derived from measurements that were made by Henry Cavendish in 1798 with a torsion balance. The value he obtained differs by only 1% from the modern value, but was not as precise. The diurnal parallax of the Sun was accurately measured during the transits of Venus in 1761 and 1769, yielding a value of (9 arcseconds, compared to the present value of ). From the value of the diurnal parallax, one can determine the distance to the Sun from the geometry o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flag Of Papua New Guinea
The flag of Papua New Guinea (Tok Pisin: ''plak bilong Papua Niugini'') was adopted on 1 July 1971. In the hoist, it depicts the Southern Cross; in the fly, a Raggiana bird-of-paradise is silhouetted. The design was chosen through a nationwide design competition in early 1971. The winning designer was Susan Karike, who was 15 at the time. Red and black have long been traditional colours of many Papua New Guinean tribes. Black-white-red was the colour of the German Empire flag, which had colonised New Guinea prior to 1918. The bird-of-paradise is also found on the national coat-of-arms. The Southern Cross shows that it is a country in the Southern Hemisphere and can be seen in Papua New Guinea. Prior to independence, the Australian administration proposed a vertical tricolour flag with blue, yellow and green bands, along with the bird of paradise and southern cross, designed by Hal Holman. The blue was said to represent the sea and islands of New Guinea, the Southern Cross wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flag Of Australia
The flag of Australia, also known as the Australian Blue Ensign, is based on the British Blue Ensign—a blue field with the Union Jack in the upper hoist quarter—augmented with a large white seven-pointed star (the Commonwealth Star) and a representation of the Southern Cross constellation, made up of five white stars (one small five-pointed star and four, larger, seven-pointed stars). Australia also has a number of other official flags representing its people and core functions of government. Its original design (with a six-pointed Commonwealth Star) was chosen in 1901 from entries in a competition held following Federation, and was first flown in Melbourne on 3 September 1901, the date proclaimed in 1996 as Australian National Flag Day. A slightly different design was approved by King Edward VII in 1903. The current seven-pointed Commonwealth Star version was introduced by a proclamation dated 8 December 1908. The dimensions were formally gazetted in 1934, and in 1954 t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Portuguese Language
Portuguese ( or, in full, ) is a western Romance language of the Indo-European language family, originating in the Iberian Peninsula of Europe. It is an official language of Portugal, Brazil, Cape Verde, Angola, Mozambique, Guinea-Bissau and São Tomé and Príncipe, while having co-official language status in East Timor, Equatorial Guinea, and Macau. A Portuguese-speaking person or nation is referred to as " Lusophone" (). As the result of expansion during colonial times, a cultural presence of Portuguese speakers is also found around the world. Portuguese is part of the Ibero-Romance group that evolved from several dialects of Vulgar Latin in the medieval Kingdom of Galicia and the County of Portugal, and has kept some Celtic phonology in its lexicon. With approximately 250 million native speakers and 24 million L2 (second language) speakers, Portuguese has approximately 274 million total speakers. It is usually listed as the sixth-most spoken language, the third-most sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IAU Working Group On Star Names
The International Astronomical Union (IAU) established a Working Group on Star Names (WGSN) in May 2016 to catalog and standardize proper names for stars for the international astronomical community. It operates under Division C – Education, Outreach and Heritage. The IAU states that it is keen to make a distinction between the terms ''name'' and ''designation''. To the IAU, ''name'' refers to the (usually colloquial) term used for a star in everyday conversation, while ''designation'' is solely alphanumerical, and used almost exclusively in official catalogues and for professional astronomy. (The WGSN notes that transliterated Bayer designations (e.g., Tau Ceti) are considered a special historical case and are treated as designations.) Terms of reference The terms of reference for the WGSN for the period 2016–2018 were approved by the IAU Executive Committee at its meeting on 6 May 2016. In summary, these are to: * establish IAU guidelines for the proposal and a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, smaller islands. With an area of , Australia is the largest country by area in Oceania and the world's List of countries and dependencies by area, sixth-largest country. Australia is the oldest, flattest, and driest inhabited continent, with the least fertile soils. It is a Megadiverse countries, megadiverse country, and its size gives it a wide variety of landscapes and climates, with Deserts of Australia, deserts in the centre, tropical Forests of Australia, rainforests in the north-east, and List of mountains in Australia, mountain ranges in the south-east. The ancestors of Aboriginal Australians began arriving from south east Asia approximately Early human migrations#Nearby Oceania, 65,000 years ago, during the Last Glacial Period, last i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northern Territory
The Northern Territory (commonly abbreviated as NT; formally the Northern Territory of Australia) is an states and territories of Australia, Australian territory in the central and central northern regions of Australia. The Northern Territory shares its borders with Western Australia to the west (129th meridian east), South Australia to the south (26th parallel south), and Queensland to the east (138th meridian east). To the north, the territory looks out to the Timor Sea, the Arafura Sea and the Gulf of Carpentaria, including Western New Guinea and other islands of the Indonesian archipelago. The NT covers , making it the third-largest Australian federal division, and List of country subdivisions by area, the 11th-largest country subdivision in the world. It is sparsely populated, with a population of only 249,000 – fewer than half as many people as in Tasmania. The largest population center is the capital city of Darwin, Northern Territory, Darwin. The archaeological hist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wardaman People
The Wardaman people are a small group of Aboriginal Australians living about South-West of Katherine, on Menngen Aboriginal Land Trust in the Northern Territory of Australia. Language Wardaman is a non Pama-Nyungan language. Though close to being a moribund language, it was, as late as the early 1990s, one of the most widely spoken Aboriginal languages in Katherine, with an estimated 30 speakers and perhaps 200 or more people who could understand it if spoken. Country The Wardaman controlled, according to Norman Tindale, some of territory from the headwaters of the southern branches of the upper Flora River, and westwards as far as the Victoria River Depot, Their southern limits lay around Jasper Gorge. The Wardaman presence, attested in post-contact times, at Delamere is historically recent. History of contact European contact with Wardaman and related peoples like the Dagoman and Yangman, was characterized from the outset by considerable violence. Eventually, as th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bayer Designation
A Bayer designation is a stellar designation in which a specific star is identified by a Greek or Latin letter followed by the genitive form of its parent constellation's Latin name. The original list of Bayer designations contained 1,564 stars. The brighter stars were assigned their first systematic names by the German astronomer Johann Bayer in 1603, in his star atlas ''Uranometria''. Bayer catalogued only a few stars too far south to be seen from Germany, but later astronomers (including Nicolas-Louis de Lacaille and Benjamin Apthorp Gould) supplemented Bayer's catalog with entries for southern constellations. Scheme Bayer assigned a lowercase Greek letter (alpha (α), beta (β), gamma (γ), etc.) or a Latin letter (A, b, c, etc.) to each star he catalogued, combined with the Latin name of the star's parent constellation in genitive (possessive) form. The constellation name is frequently abbreviated to a standard three-letter form. For example, Aldebaran in the constellation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latinisation Of Names
Latinisation (or Latinization) of names, also known as onomastic Latinisation, is the practice of rendering a ''non''-Latin name in a Latin style. It is commonly found with historical proper names, including personal names and toponyms, and in the standard binomial nomenclature of the life sciences. It goes further than romanisation, which is the transliteration of a word to the Latin alphabet from another script (e.g. Cyrillic). For authors writing in Latin, this change allows the name to function grammatically in a sentence through declension. In a scientific context, the main purpose of Latinisation may be to produce a name which is internationally consistent. Latinisation may be carried out by: * transforming the name into Latin sounds (e.g. for ), or * adding Latinate suffixes to the end of a name (e.g. for '' Meibom),'' or * translating a name with a specific meaning into Latin (e.g. for Italian ; both mean 'hunter'), or * choosing a new name based on some attribut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Effective Temperature
The effective temperature of a body such as a star or planet is the temperature of a black body that would emit the same total amount of electromagnetic radiation. Effective temperature is often used as an estimate of a body's surface temperature when the body's emissivity curve (as a function of wavelength) is not known. When the star's or planet's net emissivity in the relevant wavelength band is less than unity (less than that of a black body), the actual temperature of the body will be higher than the effective temperature. The net emissivity may be low due to surface or atmospheric properties, including greenhouse effect. Star The effective temperature of a star is the temperature of a black body with the same luminosity per ''surface area'' () as the star and is defined according to the Stefan–Boltzmann law . Notice that the total (bolometric) luminosity of a star is then , where is the stellar radius. The definition of the stellar radius is obviously not straightf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
