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Eta Geminorum
Eta Geminorum (η Geminorum, abbreviated Eta Gem, η Gem), formally named Propus , is a triple star system in the constellation of Gemini. It is a naked-eye variable star around 380 light years from the Sun. Nomenclature ''Eta Geminorum'' is the star's Bayer designation. The traditional names ''Tejat Prior'', ''Propus'' (from the Greek, meaning forward foot) and ''Praepes'' and ''Pish Pai'' (from the Persian Pīshpāy, پیشپای, meaning foreleg). In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN) to catalog and standardize proper names for stars. The WGSN's first bulletin of July 2016 included a table of the first two batches of names approved by the WGSN; which included ''Propus'' for this star. This star, along with γ Gem (Alhena), μ Gem (Tejat Posterior), ν Gem and ξ Gem (Alzirr) were ''Al Han'ah'', "the brand" (on the neck of the camel). They also were associated in ''Al Nuḥātai'', the dual form of ''Al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gemini (constellation)
Gemini is one of the constellations of the zodiac and is located in the northern celestial hemisphere. It was one of the 48 constellations described by the 2nd century AD astronomer Ptolemy, and it remains one of the 88 modern constellations today. Its name is Latin for ''twins'', and it is associated with the twins Castor and Pollux in Greek mythology. Its old astronomical symbol is (♊︎). Location Gemini lies between Taurus to the west and Cancer to the east, with Auriga and Lynx to the north, Monoceros and Canis Minor to the south and Orion to the south-west. In classical antiquity, Cancer was the location of the Sun on the first day of summer (June 21). During the first century AD, axial precession shifted it into Gemini. In 1990, the location of the Sun on the first day of summer moved from Gemini into Taurus, where it will remain until the 27th century AD and then move into Aries. The Sun will move through Gemini from June 21 to July 20 through 2062. Gemini i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Persian Language
Persian (), also known by its endonym Farsi (, ', ), is a Western Iranian language belonging to the Iranian branch of the Indo-Iranian subdivision of the Indo-European languages. Persian is a pluricentric language predominantly spoken and used officially within Iran, Afghanistan, and Tajikistan in three mutually intelligible standard varieties, namely Iranian Persian (officially known as ''Persian''), Dari Persian (officially known as ''Dari'' since 1964) and Tajiki Persian (officially known as ''Tajik'' since 1999).Siddikzoda, S. "Tajik Language: Farsi or not Farsi?" in ''Media Insight Central Asia #27'', August 2002. It is also spoken natively in the Tajik variety by a significant population within Uzbekistan, as well as within other regions with a Persianate history in the cultural sphere of Greater Iran. It is written officially within Iran and Afghanistan in the Persian alphabet, a derivation of the Arabic script, and within Tajikistan in the Tajik alphabet, a der ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Messier 35
Messier 35 or M35, also known as NGC 2168, is a relatively close open cluster of stars in the west of Gemini, at about the declination of the sun when the latter is at June solstice. It was discovered by Philippe Loys de Chéseaux around 1745 and independently discovered by John Bevis before 1750. It is scattered over part of the sky almost the size of the full moon and is away. The compact open cluster NGC 2158 lies directly southwest of it. Leonard & Merritt (1989) computed the mass of M35 using a statistical technique based on proper motion velocities of its stars. The mass within the central was found to be between 1600 and 3200 solar masses, consistent with the mass of a realistic stellar population within the same radius. Bouy et al. in 2015 found a mass of around within the central . There are 305 stars that can be intrinsically shown to be extremely likely to be members, and up to 4,349 averaging the 50% membership probability, from the kinematic (such as paralla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Open Cluster
An open cluster is a type of star cluster made of up to a few thousand stars that were formed from the same giant molecular cloud and have roughly the same age. More than 1,100 open clusters have been discovered within the Milky Way galaxy, and many more are thought to exist. They are loosely bound by mutual gravity, gravitational attraction and become disrupted by close encounters with other clusters and clouds of gas as they orbit the Galactic Center. This can result in a migration to the main body of the galaxy and a loss of cluster members through internal close encounters. Open clusters generally survive for a few hundred million years, with the most massive ones surviving for a few billion years. In contrast, the more massive globular clusters of stars exert a stronger gravitational attraction on their members, and can survive for longer. Open clusters have been found only in spiral galaxy, spiral and irregular galaxy, irregular galaxies, in which active star formation is o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Castor (star)
Castor is the second-brightest object in the zodiac constellation of Gemini. It has the Bayer designation α Geminorum, which is Latinised to Alpha Geminorum and abbreviated Alpha Gem or α Gem. With an apparent visual magnitude of 1.93, it is one of the brightest stars in the night sky. Castor appears singular to the naked eye, but it is actually a sextuple star system organized into three binary pairs. Although it is the 'α' (alpha) member of the constellation, it is fainter than 'β' (beta) Geminorum, Pollux. Stellar system Hierarchy of orbits in the Castor system Castor is a multiple star system made up of six individual stars; there are three visual components, all of which are spectroscopic binaries. Appearing to the naked eye as a single star, Castor was first recorded as a double star in 1718 by James Pound, but it may have been resolved into at least two sources of light by Cassini as early as 1678. The separation between the binar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chinese Language
Chinese (, especially when referring to written Chinese) is a group of languages spoken natively by the ethnic Han Chinese majority and many minority ethnic groups in Greater China. About 1.3 billion people (or approximately 16% of the world's population) speak a variety of Chinese as their first language. Chinese languages form the Sinitic branch of the Sino-Tibetan languages family. The spoken varieties of Chinese are usually considered by native speakers to be variants of a single language. However, their lack of mutual intelligibility means they are sometimes considered separate languages in a family. Investigation of the historical relationships among the varieties of Chinese is ongoing. Currently, most classifications posit 7 to 13 main regional groups based on phonetic developments from Middle Chinese, of which the most spoken by far is Mandarin (with about 800 million speakers, or 66%), followed by Min (75 million, e.g. Southern Min), Wu (74 million, e.g. Shangh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pinyin
Hanyu Pinyin (), often shortened to just pinyin, is the official romanization system for Standard Mandarin Chinese in China, and to some extent, in Singapore and Malaysia. It is often used to teach Mandarin, normally written in Chinese form, to learners already familiar with the Latin alphabet. The system includes four diacritics denoting tones, but pinyin without tone marks is used to spell Chinese names and words in languages written in the Latin script, and is also used in certain computer input methods to enter Chinese characters. The word ' () literally means "Han language" (i.e. Chinese language), while ' () means "spelled sounds". The pinyin system was developed in the 1950s by a group of Chinese linguists including Zhou Youguang and was based on earlier forms of romanizations of Chinese. It was published by the Chinese Government in 1958 and revised several times. The International Organization for Standardization (ISO) adopted pinyin as an international standard ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chinese Constellations
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 tradition. The Song dynasty (13th-century) Suzhou planisphere shows a total of 283 asterisms, comprising a total of 1,565 individual stars. The asterisms are divided into four groups, the Twenty-Eight Mansions (, ''Èrshíbā Xiù'') along the ecliptic, and the Three Enclosures of the northern sky. The southern sky was added as a fifth group in the late Ming Dynasty based on European star charts, comprising an additional 23 asterisms. The Three Enclosures (, ''Sān Yuán'') include the Purple Forbidden Enclosure, which is centered on the north celestial pole and includes those stars which could be seen year-round,Needham, J.Astronomy in Ancient and Medieval China. ''Philosophical Transactions of the Royal Society of London''. Series A, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xi Geminorum
Xi Geminorum (ξ Geminorum, abbreviated Xi Gem, ξ Gem), formally named Alzirr , is a star in the zodiac constellation of Gemini. It forms one of the four feet of the outline demarcating the Gemini twins. The star has an apparent visual magnitude of 3.35, which is bright enough for it to be seen with the naked eye. From stellar parallax measurements, its distance from the Sun can be estimated as . Nomenclature ''ξ Geminorum'' ( Latinised to ''Xi Geminorum'') is the star's Bayer designation. It bore the traditional name of ''Al Zirr'' or ''Alzirr'', from the Arabic الزِرّ ''al-zirr'' "the button". In 2016, the IAU organized a Working Group on Star Names (WGSN) to catalog and standardize proper names for stars. The WGSN approved the name ''Alzirr'' for this star on 30 June 2017 and it is now so included in the List of IAU-approved Star Names. This star, along with Gamma Geminorum (Alhena), Mu Geminorum, Nu Geminorum and Eta Geminorum were ''al-hanʽah'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nu Geminorum
Nu Geminorum, Latinized from ν Geminorum, is a triple star system in the constellation Gemini. It has an apparent visual magnitude of 4.16, which is bright enough to be visible to the naked eye on a dark night. Based upon an annual parallax shift of 5.99 mas, it is located at a distance of roughly 540 light years from the Sun. The position of this system near the ecliptic means it is subject to lunar occultations. The inner components of this multiple star system have an orbital period of about 54 days and a nearly circular orbit with an eccentricity of 0.056. There is some uncertainty in the spectral type, with classifications ranging from a main sequence star to a giant. Orbiting the inner pair is a classical Be star, with an orbital period of 19.1 years and an eccentricity of 0.24. The two orbits are co-directional and roughly coplanar. The system is overall dynamically stable, and shows no signs of Kozai-Lidov cycles In celestial mechanics ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mu Geminorum
Mu Geminorum or μ Geminorum, formally named Tejat (), is a single star in the northern constellation of Gemini. From parallax measurements obtained during the Hipparcos mission, it is roughly distant from the Sun. The position of the star near the ecliptic means that it is subject to lunar occultations. Mu Geminorum forms the primary or 'A' component of a double star system designated WDS J06230+2231 along with UCAC2 39641417 (also designated WDS J06230+2231BC), itself a binary pair. Nomenclature ''μ Geminorum'' ( Latinised to ''Mu Geminorum'') is the star's Bayer designation. WDS J06230+2231 is the double star's designation in the Washington Double Star Catalog. The designations of the double star's components as WDS J06230+2231A and BC derive from the convention used by the Washington Multiplicity Catalog (WMC) for multiple star systems, and adopted by the International Astronomical Union (IAU). Mu Geminorum bore the traditional name of ''Tejat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
