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Chi Sagittarii
The Bayer designation Chi Sagittarii (χ Sagittarii) is shared by three star systems in the zodiac constellation of Sagittarius. The brightest of these, χ1 Sagittarii and χ3 Sagittarii, are separated by 0.56° on the sky. The dimmer star χ2 Sagittarii is located between them, 0.10° from χ1, and is too faint to be seen with the naked eye. In 1977, the Wow! signal came from the direction of these stars. * χ1 Sagittarii, 47 Sgr, HR 7362 * χ2 Sagittarii, 48 Sgr * χ3 Sagittarii, 49 Sgr, HR 7363 Name and etymology These three χ star, together with φ Sgr, σ Sgr, ζ Sgr and τ Sgr were ''Al Naʽām al Ṣādirah'' (النعم السادرة), the Returning Ostriches. According to the catalogue of stars in the ''Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars'', ''Al Naʽām al Ṣādirah'' or ''Namalsadirah'' was originally the title for four stars: φ Sgr as ''Namalsadirah I'', τ Sgr as ''Namalsadirah II'', χ1 Sgr as ''Namalsadira ... [...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] |
Sigma Sagittarii
Sigma Sagittarii, Latinized from σ Sagittarii; formally named Nunki , is the second-brightest star in the constellation of Sagittarius. It has an apparent magnitude of +2.05, making it readily visible to the naked eye. The distance to this star, determined using parallax measurements from the Hipparcos astrometry satellite, yields a value of approximately from the Sun. Properties Sigma Sagittarii has a spectrum matching a stellar classification of B2.5 V, which indicates this is a B-type main-sequence star. Its total luminosity is 3300 times that of the Sun while it has a surface temperature of 18,890 K. X-ray emission has been detected from this star, which has an estimated X-ray luminosity of . It has a 10th magnitude optical companion located 5.2 arcminutes away. It is 3.45 degrees south of the ecliptic, so it can be occulted by the Moon and rarely by planets. The last occultation by a planet took place on November 17, 1981, when it was occulted by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jet Propulsion Laboratory
The Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center in the City of La Cañada Flintridge, California, United States. Founded in the 1930s by Caltech researchers, JPL is owned by NASA and managed by the nearby California Institute of Technology (Caltech). The laboratory's primary function is the construction and operation of planetary robotic spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating the NASA Deep Space Network. Among the laboratory's major active projects are the Mars 2020 mission, which includes the ''Perseverance'' rover and the '' Ingenuity'' Mars helicopter; the Mars Science Laboratory mission, including the ''Curiosity'' rover; the InSight lander (''Interior Exploration using Seismic Investigations, Geodesy and Heat Transport''); the ''Mars Reconnaissance Orbiter''; the ''Juno'' spacecraft orbiting Jupiter; the ''SMAP'' satellite for earth surface s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
52 Sagittarii
52 Sagittarii is a binary star system in the southern constellation of Sagittarius. It has the Bayer designation h2 Sagittarii, while ''52 Sagittarii'' is the Flamsteed designation. This system is visible to the naked eye as a faint, blue-white hued point of light with an apparent visual magnitude of 4.59. It is located approximately 190 light years away based on parallax, but is drifting closer with a radial velocity of −19 km/s. The primary component is a B-type main-sequence star with a stellar classification of B8/9V. Garrison and Gray (1994) assigned it a class of , displaying the calcium K line of a B8 class star, the hydrogen lines of a B9 star, and the helium lines of an A0 star, along with overabundances of strontium and iron. It is around 57 million years old with three times the mass of the Sun and about 2.1 times the Sun's radius. It is radiating 60.5 times the luminosity of the Sun from its photosphere at an effective temperature of 10,592 K. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dipper (Chinese Constellation)
The Dipper mansion (斗宿, pinyin: Dǒu Xiù) is one of the Twenty-eight mansions of the Chinese constellations. It is one of the northern mansions of the Black Tortoise. In Taoism, it is known as the "Six Stars of the Southern Dipper" (南斗六星, Nándǒu liù xīng), in contrast to the Big Dipper The Big Dipper ( US, Canada) or the Plough ( UK, Ireland) is a large asterism consisting of seven bright stars of the constellation Ursa Major; six of them are of second magnitude and one, Megrez (δ), of third magnitude. Four define a "bowl" ... north to this mansion. Asterisms Stars * ζ Sgr * τ Sgr * σ Sgr * φ Sgr * λ Sgr * μ Sgr {{DEFAULTSORT:Dipper (Chinese Constellation) Chinese constellations ... [...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] |
Tau Sagittarii
Tau Sagittarii (Tau Sgr, τ Sagittarii, τ Sgr) is a star in the southern zodiac constellation of Sagittarius. Description With an apparent visual magnitude of +3.3, this is one of the brighter members of the constellation. The distance of this star from Earth is roughly , based upon parallax measurements. This is a spectral type K1 giant star with about . The stellar envelope is slightly cooler than the Sun with an effective temperature of 4,459 K, giving the star a light orange color. The interferometry-measured angular diameter of this star, after correcting for limb darkening, is , which, at its estimated distance, equates to a physical radius of about 16 times the radius of the Sun. τ Sagittarii is a suspected double star although no companion has been confirmed yet. A lower metal content (Fe to H ratio is 54% lower than the sun's) and a high peculiar velocity (64 km/s, four times the local average) relative to the Sun suggest the star is a vis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zeta Sagittarii
Zeta Sagittarii (ζ Sagittarii, abbreviated Zeta Sgr, ζ Sgr) is a triple star system and the third-brightest star in the constellation of Sagittarius. Based upon parallax measurements, it is about from the Sun. The three components are designated Zeta Sagittarii A (officially named Ascella , the traditional name for the entire system) and B, themselves forming a binary pair, and a smaller companion star, C. Nomenclature ''ζ Sagittarii'' ( Latinised to ''Zeta Sagittarii'') is the system's Bayer designation. The designations of the two components as ''ζ Sagittarii A'', ''B'' and ''C'' 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 name ''Ascella'', from a Late Latin word meaning ''armpit''. In the catalogue of stars in the ''Calendarium'' of Al Achsasi al Mouakket, this star was designated ''Thalath al Sadirah'', w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phi Sagittarii
Phi Sagittarii, Latinized from φ Sagittarii, is a star in the southern constellation of Sagittarius. With an apparent visual magnitude of 3.17, it is the ninth-brightest star in the constellation and is readily visible to the naked eye. Parallax measurements place it at a distance of roughly from the Earth. It is receding with a radial velocity of +21.5 km/s. The stellar classification of this star has been rated at B8.5 III, with the luminosity class of III indicating it is a giant star evolved away from the main sequence after it has exhausted the hydrogen at its core. This energy is being radiated from the star's outer envelope at an effective temperature of , which produces the blue-white hue typical of B-type stars. In the past, this star catalogued as a spectroscopic binary and a companion was apparently detected through lunar occultation. However, it is most likely a solitary star and any nearby stars are merely optical companions. Name and ety ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Star System
A star system or stellar system is a small number of stars that orbit each other, bound by gravitational attraction. A large group of stars bound by gravitation is generally called a '' star cluster'' or '' galaxy'', although, broadly speaking, they are also star systems. Star systems are not to be confused with planetary systems, which include planets and similar bodies (such as comets). A star system of two stars is known as a '' binary star'', ''binary star system'' or ''physical double star''. If there are no tidal effects, no perturbation from other forces, and no transfer of mass from one star to the other, such a system is stable, and both stars will trace out an elliptical orbit around the barycenter of the system indefinitely. ''(See Two-body problem)''. Examples of binary systems are Sirius, Procyon and Cygnus X-1, the last of which probably consists of a star and a black hole. Multiple star systems A multiple star system consists of three or more stars that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chi3 Sagittarii
Chi3 Sagittarii (χ3 Sagittarii) is a solitary, orange-hued star in the zodiac constellation of Sagittarius. It is faintly visible to the naked eye with an apparent visual magnitude of +5.45. Based upon an annual parallax shift of 6.53 mas as seen from Earth, it is located roughly 500 light years from the Sun. It is receding from the Earth with a radial velocity of 39.6 km/s. This is an evolved, K-type giant star with a stellar classification of K3 III. It is a suspected optical variable star with a magnitude range of 5.42 to 5.46. At infrared wavelengths, it shows large amplitude variation with a period of 505 days. The star has expanded to about 37 times the Sun's radius and is radiating 301 times the solar luminosity from its photosphere at an 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. Effec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chi1 Sagittarii
Chi1 Sagittarii (χ1 Sagittarii) is a binary star system in the zodiac constellation of Sagittarius. The pair have a combined apparent visual magnitude of +5.03, which is bright enough to be seen with the naked eye. Based upon an annual parallax shift of 12.95 mas as seen from Earth, it is located around 252 light years from the Sun. It is advancing through space in the general direction of the Earth with a radial velocity of −43.4 km/s. This is a visual binary with an orbital period of 5.72 years, an eccentricity of 0.710, and an angular semimajor axis of 69 mas. The primary, component A, is an A-type star showing a mixed spectrum that matches a stellar classification of A3/5 IV/V. Helmut Abt classified it as an Am star with a spectral type of kA5hF0VmF0. This notation indicates it has the calcium K-lines of an A5 star, and the hydrogen and metal lines of an F0 star. It is around 393 million years old and is spinning with a proje ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
