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Xi Draconis
Xi Draconis (ξ Draconis, abbreviated Xi Dra, ξ Dra) is a double or binary star in the northern circumpolar constellation of Draco. It has an apparent visual magnitude of 3.75. Based upon parallax measurements, it is located at a distance of from the Sun. At this distance, the apparent magnitude is diminished by 0.03 from extinction caused by intervening gas and dust. The two components are designated Xi Draconis A (officially named Grumium , a traditional name for the system) and B. Nomenclature ''ξ Draconis'' ( Latinised to ''Xi Draconis'') is the system's Bayer designation. The designations of the two components as ''Xi Draconis A'' and ''B'' derive from the convention used by the Washington Multiplicity Catalog (WMC) for multiple star systems, and adopted by the International Astronomical Union (IAU). It bore the traditional names ''Grumium''. This is a graphic corruption of the Latin ''Grunnum'' 'snout', as Ptolemy had described this star as being on the jawbone o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xi Draconis
Xi Draconis (ξ Draconis, abbreviated Xi Dra, ξ Dra) is a double or binary star in the northern circumpolar constellation of Draco. It has an apparent visual magnitude of 3.75. Based upon parallax measurements, it is located at a distance of from the Sun. At this distance, the apparent magnitude is diminished by 0.03 from extinction caused by intervening gas and dust. The two components are designated Xi Draconis A (officially named Grumium , a traditional name for the system) and B. Nomenclature ''ξ Draconis'' ( Latinised to ''Xi Draconis'') is the system's Bayer designation. The designations of the two components as ''Xi Draconis A'' and ''B'' derive from the convention used by the Washington Multiplicity Catalog (WMC) for multiple star systems, and adopted by the International Astronomical Union (IAU). It bore the traditional names ''Grumium''. This is a graphic corruption of the Latin ''Grunnum'' 'snout', as Ptolemy had described this star as being on the jawbone o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Crater-class Cargo Ship
The ''Crater''-class cargo ship were converted EC2-S-C1 type, Liberty cargo ships, constructed by the United States Maritime Commission (USMC) for use by the US Navy during World War II. The designation 'EC2-S-C1': 'EC' for Emergency Cargo, '2' for a ship between long ( Load Waterline Length), 'S' for steam engines, and 'C1' for design C1. The class was named for the lead ship of its type, , with most ships in the class being named for astronomical bodies. Its 65 hulls were among the largest US Navy cargo ship classes. The ships were propelled by a reciprocating steam engine using a single screw with a power of shaft. Notable incidents * USS ''Aludra'' (AK-72) Lost in action from Japanese torpedo on 23 June 1943 south of Makira The island of Makira (also known as San Cristobal and San Cristóbal) is the largest island of Makira-Ulawa Province in the Solomon Islands. It is third most populous island after Malaita and Guadalcanal, with a population of 55,126 as of 2020. .. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Navy
The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage of its active battle fleet alone exceeding the next 13 navies combined, including 11 allies or partner nations of the United States as of 2015. It has the highest combined battle fleet tonnage (4,635,628 tonnes as of 2019) and the world's largest aircraft carrier fleet, with eleven in service, two new carriers under construction, and five other carriers planned. With 336,978 personnel on active duty and 101,583 in the Ready Reserve, the United States Navy is the third largest of the United States military service branches in terms of personnel. It has 290 deployable combat vessels and more than 2,623 operational aircraft . The United States Navy traces its origins to the Continental Navy, which was established during the American Revo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
USS Grumium (AK-112)
USS ''Grumium'' (AK-112/IX-174/AVS-3) was a and aviation supply ship in the service of the US Navy in World War II. Named after the star Grumium in the constellation Draco, it was the only ship of the Navy to bear this name. Construction ''Grumium'' was laid down under a Maritime Commission (MARCOM) contract, MCE hull 443, on 12 November 1942, as the liberty ship SS ''William G. McAdoo'', by the Permanente Metals Corporation, Yard No. 2, in Richmond, California. She was launched on 20 December 1942, sponsored by Mrs. T. Y. Sturtevant. ''William G. McAdoo'' was acquired by the Navy on 5 October 1943. The ship was converted for Navy use by the Todd Shipyards in Seattle, Washington and commissioned on 20 October 1943. Service history ''Grumium'' loaded supplies at San Francisco 9 November, and got underway from San Pedro 19 November 1943, bound for Pago Pago. The ship unloaded drum gas there and at Funafuti 8 to 11 December, after which she proceeded to Kwajalein 6 March, and E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chinese Star Names
Chinese star names (Chinese: , ''xīng míng'') are named according to ancient Chinese astronomy and astrology. The sky is divided into star mansions (, ''xīng xiù'', also translated as "lodges") and asterisms (, ''xīng guān''). The system of 283 asterisms under Three Enclosures and Twenty-eight Mansions was established by Chen Zhuo of the Three Kingdoms period, who synthesized ancient constellations and the asterisms created by early astronomers Shi Shen, Gan De and Wuxian. Since the Han and Jin Dynasties, stars have been given reference numbers within their asterisms in a system similar to the Bayer or Flamsteed designations, so that individual stars can be identified. For example, Deneb (α Cyg) is referred to as (''Tiān Jīn Sì'', the Fourth Star of Celestial Ford). In the Qing Dynasty, Chinese knowledge of the sky was improved by the arrival of European star charts. ''Yixiang Kaocheng'', compiled in mid-18th century by then deputy Minister of Rites Ignaz Kögler, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iota Herculis
Iota Herculis (ι Herculis, ι Her) is a fourth-magnitude variable star system in the constellation Hercules, consisting of at least four stars all about away. The brightest is a β Cephei variable, a pulsating star. Visibility Iota Herculis is dim enough that in cities with a lot of light pollution it is unlikely to be visible with the naked eye. In rural areas it will usually be visible, and for much of the Northern Hemisphere the star is circumpolar and visible year around. Pole star As a visible star, the proximity of Iota Herculis to the precessional path the Earth's North Pole traces across the celestial sphere makes it a pole star, a title currently held by Polaris. In 10,000 BCE it was the pole star, and in the future it will be again. While Polaris is only 0.5° off the precessional path Iota Herculis is 4° off. Properties Iota Herculis is a B-type subgiant star that is at the end of its hydrogen fusion stage. With a stellar classification B3IV, it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asterism (astronomy)
An asterism is an observed pattern or group of stars in the sky. Asterisms can be any identified pattern or group of stars, and therefore are a more general concept than the formally defined 88 constellations. Constellations are based on asterisms, but unlike asterisms, constellations outline and today completely divide the sky and all its celestial objects into regions around their central asterisms. For example, the asterism known as the Big Dipper comprises the seven brightest stars in the constellation Ursa Major. Another is the asterism of the Southern Cross, within the constellation of Crux. Asterisms range from simple shapes of just a few stars to more complex collections of many stars covering large portions of the sky. The stars themselves may be bright naked-eye objects or fainter, even telescopic, but they are generally all of a similar brightness to each other. The larger brighter asterisms are useful for people who are familiarizing themselves with the night sky. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Purple Forbidden Enclosure
The Purple Forbidden enclosure ( Zǐ wēi yuán) is one of the San Yuan ( Sān yuán) or Three Enclosures Traditional Chinese astronomy has a system of dividing the celestial sphere into asterisms or constellations, known as "officials" ( Chinese ''xīng guān''). The Chinese asterisms are generally smaller than the constellations of Hellenistic .... Stars and constellations of this group lie near the north celestial pole and are visible all year from temperate latitudes in the Northern Hemisphere. Asterisms The asterisms are : See also * Twenty-eight mansions References Chinese constellations Chinese astrology {{china-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chinese Astronomy
Astronomy in China has a long history stretching from the Shang dynasty, being refined over a period of more than 3,000 years. The ancient Chinese people have identified stars from 1300 BCE, as Chinese star names later categorized in the twenty-eight mansions have been found on oracle bones unearthed at Anyang, dating back to the mid-Shang dynasty. The core of the "mansion" (宿 ''xiù'') system also took shape around this period, by the time of King Wu Ding (1250–1192 BCE). Detailed records of astronomical observations began during the Warring States period (fourth century BCE) and flourished from the Han period onward. Chinese astronomy was equatorial, centered on close observation of circumpolar stars, and was based on different principles from those in traditional Western astronomy, where heliacal risings and settings of zodiac constellations formed the basic ecliptic framework. Joseph Needham has described the ancient Chinese as the most persistent and accurate obser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nu Draconis
Nu Draconis (also known as ν Dra, ν Draconis, or traditionally as Kuma ) is a double star in the constellation Draco. The respective components are designated ν1 Draconis and ν2 Draconis. The second component is a spectroscopic binary star system. This star, along with β Dra (Rastaban), γ Dra (Eltanin), μ Dra (Alrakis) and ξ Dra (Grumium) were Al ʽAwāïd, "the Mother Camels", which was later known as the Quinque Dromedarii. In Chinese, (), meaning '' Celestial Flail'', refers to an asterism consisting of ν Draconis, ξ Draconis, β Draconis, γ Draconis and ι Herculis. Consequently, the Chinese name for ν Draconis itself is (, en, the Second Star of Celestial Flail.) , Hong Kong Spac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mu Draconis
Mu Draconis (μ Draconis, abbreviated Mu Dra, μ Dra) is a multiple star system near the head of the constellation of Draco. With a combined magnitude of 4.92, it is visible to the naked eye. Based on parallax estimates by the Hipparcos spacecraft, it is located approximately 89 light-years from the Sun. The system consists of a single primary star (designated Mu Draconis A, officially named Alrakis from the traditional name of the system), a secondary binary pair (Mu Draconis B) and a further single star (C). B's two components are designated Mu Draconis Ba and Bb. Mu Draconis A and Ba are nearly identical F-type main-sequence stars, with masses of and , respectively. Both have the spectral class of F5V, and have similar apparent magnitude, at 5.66 and 5.69, respectively. The secondary, Mu Draconis B, has a drifting radial velocity, and is itself a spectroscopic binary with an orbital period of 2,270 days.SB9 catalog entry The distance between both st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
