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Aldebaran
Aldebaran (Arabic: “The Follower”, "الدبران") is the brightest star in the zodiac constellation of Taurus. It has the Bayer designation α Tauri, which is Latinized to Alpha Tauri and abbreviated Alpha Tau or α Tau. Aldebaran varies in brightness from an apparent visual magnitude 0.75 down to 0.95, making it (typically) the fourteenth-brightest star in the night sky. It is located at a distance of approximately 65 light-years from the Sun. The star lies along the line of sight to the nearby Hyades cluster. Aldebaran is a giant star that is cooler than the Sun with a surface temperature of , but its radius is about 44 times the Sun's, so it is over 400 times as luminous. It spins slowly and takes 520 days to complete a rotation. Aldebaran is believed to host a planet several times the mass of Jupiter, named . The planetary exploration probe Pioneer 10 is heading in the general direction of the star and should make its closest approach in about two million ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aldebaran B
Aldebaran b is a candidate exoplanet orbiting the orange giant star Aldebaran, 65 light-years away. It was initially detected in 1993, but was considered doubtful until 2015, when researchers came to a conclusion that there is likely an exoplanet orbiting Aldebaran, consistent with the original calculations, but also compatible with stellar activity. However, in 2019, new data placed doubts on its existence again. Physical properties Mass and orbit Aldebaran b is a giant exoplanet with at least 5.8 times the mass of Jupiter. It orbits at a distance about 45% farther than Earth does from the Sun. The equilibrium temperature of this planet is likely to be around , as it is strongly irradiated by its giant host star. Nevertheless, when Aldebaran was a main sequence star, it is likely that the planet had an equilibrium temperature comparable to that of the Earth. Host star The host star, Aldebaran, is an orange giant star, meaning it has moved off from the main sequence a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taurus (constellation)
Taurus (Latin for "the Bull") is one of the constellations of the zodiac and is located in the northern celestial hemisphere. Taurus is a large and prominent constellation in the Northern Hemisphere's winter sky. It is one of the oldest constellations, dating back to the Early Bronze Age at least, when it marked the location of the Sun during the spring equinox. Its importance to the agricultural calendar influenced various bull figures in the mythologies of Ancient Sumer, Akkad, Assyria, Babylon, Egypt, Greece, and Rome. Its old astronomical symbol is (♉︎), which resembles a bull's head. A number of features exist that are of interest to astronomers. Taurus hosts two of the nearest open clusters to Earth, the Pleiades and the Hyades, both of which are visible to the naked eye. At first magnitude, the red giant Aldebaran is the brightest star in the constellation. In the northeast part of Taurus is Messier 1, more commonly known as the Crab Nebula, a supernova remnant co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pioneer 10
''Pioneer 10'' (originally designated Pioneer F) is an American space probe, launched in 1972 and weighing , that completed the first mission to the planet Jupiter. Thereafter, ''Pioneer 10'' became the first of five artificial objects to achieve the escape velocity needed to leave the Solar System. This space exploration project was conducted by the NASA Ames Research Center in California. The space probe was manufactured by TRW Inc. ''Pioneer 10'' was assembled around a hexagonal bus with a diameter parabolic dish high-gain antenna, and the spacecraft was spin stabilized around the axis of the antenna. Its electric power was supplied by four radioisotope thermoelectric generators that provided a combined 155 watts at launch. It was launched on March 3, 1972, at 01:49:00 UTC (March 2 local time), by an Atlas-Centaur expendable vehicle from Cape Canaveral, Florida. Between July 15, 1972, and February 15, 1973, it became the first spacecraft to traverse the asteroid belt. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyades (star Cluster)
The Hyades (; Greek Ὑάδες, also known as Caldwell 41, Collinder 50, or Melotte 25) is the nearest open cluster and one of the best-studied star clusters. Located about away from the Sun, it consists of a roughly spherical group of hundreds of stars sharing the same age, place of origin, chemical characteristics, and motion through space.Bouvier J, Kendall T, Meeus G, Testi L, Moraux E, Stauffer JR, James D, Cuillandre J-C, Irwin J, McCaughrean MJ, Baraffe I, Bertin E. (2008) Brown dwarfs and very low mass stars in the Hyades cluster: a dynamically evolved mass function. ''Astronomy & Astrophysics'', 481: 661-672. Abstract at http://adsabs.harvard.edu/abs/2008A%26A...481..661B. From the perspective of observers on Earth, the Hyades Cluster appears in the constellation Taurus, where its brightest stars form a "V" shape along with the still-brighter Aldebaran. However, Aldebaran is unrelated to the Hyades, as it is located much closer to Earth and merely happens to lie alon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
J Band (infrared)
In infrared astronomy, the J band refers to an atmospheric transmission window (1.1 to 1.4 um) centred on 1.25 micrometres (in the near-infrared). Betelgeuse is the brightest near-IR source in the sky with a J band magnitude of −2.99. The next brightest stars in the J band are Antares (−2.7), R Doradus (−2.6), Arcturus (−2.2), and Aldebaran (−2.1). In the J band Sirius Sirius is the list of brightest stars, brightest star in the night sky. Its name is derived from the Ancient Greek language, Greek word , or , meaning 'glowing' or 'scorching'. The star is designated α Canis Majoris, Latinisation ... is the 9th brightest star. References Electromagnetic spectrum Infrared imaging {{astronomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slow Irregular Variable
A slow irregular variable (ascribed the GCVS types L, LB and LC) is a variable star that exhibit no or very poorly defined periodicity in their slowly changing light emissions. These stars have often been little-studied, and once more is learnt about them, they are reclassified into other categories such as semiregular variables. Nomenclature Irregular variable stars were first given acronyms based on the letter "I": ''Ia'', ''Ib''. and ''Ic''. These were later refined so that the I codes were used "nebular" or "rapidly irregular" variable stars such as T Tauri and Orion variables. The remaining irregular stars, cool slowly varying giants and supergiants of type Ib or Ic were reassigned to Lb and Lc. When the General Catalogue of Variable Stars standardised its acronyms to be all uppercase, the codes LB and LC were used. Type Lb ''Slow irregular variables of late spectral types ( K, M, C, S); as a rule, they are giants'' The GCVS also claims to give this type to slow irregular ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zodiac
The zodiac is a belt-shaped region of the sky that extends approximately 8° north or south (as measured in celestial latitude) of the ecliptic, the Sun path, apparent path of the Sun across the celestial sphere over the course of the year. The paths of the Moon and visible planets are within the belt of the zodiac. In Western astrology, and formerly astronomy, the zodiac is divided into astrological sign, twelve signs, each occupying 30° of celestial longitude and roughly corresponding to the following star constellations: Aries (astrology), Aries, Taurus (astrology), Taurus, Gemini (astrology), Gemini, Cancer (astrology), Cancer, Leo (astrology), Leo, Virgo (astrology), Virgo, Libra (astrology), Libra, Scorpio (astrology), Scorpio, Sagittarius (astrology), Sagittarius, Capricorn (astrology), Capricorn, Aquarius (astrology), Aquarius, and Pisces (astrology), Pisces. These astrological signs form a celestial coordinate system, or more specifically an ecliptic coordinate sys ... [...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] |
Giant Star
A giant star is a star with substantially larger radius and luminosity than a main sequence, main-sequence (or ''dwarf'') star of the same effective temperature, surface temperature.Giant star, entry in ''Astronomy Encyclopedia'', ed. Patrick Moore, New York: Oxford University Press, 2002. . They lie above the main sequence (luminosity class V in the Spectral classification#Yerkes spectral classification, Yerkes spectral classification) on the Hertzsprung–Russell diagram and correspond to luminosity classes II and III.giant, entry in ''The Facts on File Dictionary of Astronomy'', ed. John Daintith and William Gould, New York: Facts On File, Inc., 5th ed., 2006. . The terms ''giant'' and ''dwarf'' were coined for stars of quite different luminosity despite similar temperature or spectral type by Ejnar Hertzsprung about 1905. Giant stars have radii up to a few hundred times the solar radii, Sun and luminosities between 10 and a few thousand times that of the Sun. Stars still mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Brightest Stars
This is a list of stars arranged by their apparent magnitude – their brightness as observed from Earth. It includes all stars brighter than magnitude +2.50 in visible light, measured using a ''V''-band filter in the UBV photometric system. Stars in binary systems (or other multiples) are listed by their ''total'' or ''combined'' brightness if they appear as a single star to the naked eye, or listed separately if they do not. As with all magnitude systems in astronomy, the scale is logarithmic and inverted i.e. lower/more negative numbers are brighter. Most stars on this list appear bright from Earth because they are nearby, not because they are intrinsically luminous. For a list which compensates for the distances, converting the ''apparent'' magnitude to the ''absolute'' magnitude, see the list of most luminous stars. Measurement The Sun is the brightest star as viewed from Earth, at −26.74 mag. The second brightest is Sirius at −1.46 mag. For c ... [...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] |
Flamsteed Designation
A Flamsteed designation is a combination of a number and constellation name that uniquely identifies most naked eye stars in the modern constellations visible from southern England. They are named for John Flamsteed who first used them while compiling his '' Historia Coelestis Britannica''. (Flamsteed used a telescope, and the catalog also includes some stars which are relatively bright but not necessarily visible with the naked eye.) Description Flamsteed designations for stars are similar to Bayer designations, except that they use numbers instead of Greek and Roman letters. Each star is assigned a number and the Latin genitive of the constellation it lies in (see 88 modern constellations for a list of constellations and the genitive forms of their names). Flamsteed designations were assigned to 2554 stars. The numbers were originally assigned in order of increasing right ascension within each constellation, but due to the effects of precession they are now slightly out of o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
