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The name Arcturus may refer to Arcturus, the star Arcturus a place in The Hitchhikers Guide to the Galaxy Arcturus in works of fiction Arcturus (band) Arcturus is a computer role-playing game by Gravity Corp. ... Image File history File links Emblem-important. ...

Arcturus (α Boo / α Boötis / Alpha Boötis) (IPA: /ɑrkˈtjʊərəs/) is the brightest star in the constellation Boötes, and the third brightest star in the night sky, with a visual magnitude of −0.05, after Sirius and Canopus, although it is fainter than the combined light of the two main components of Alpha Centauri, which are too close together for the eye to resolve as separate sources of light, making Arcturus appear to be the fourth brightest. It is the second brightest star visible from northern latitudes and the brightest star in the northern celestial hemisphere. The star is in the Local Interstellar Cloud. File links The following pages link to this file: Arcturus Boötes Category:Bootes constellation Categories: GFDL images | Maps of the constellations ... In astronomy, an epoch is a moment in time for which celestial coordinates or orbital elements are specified. ... This article is about the star grouping. ... From the dawn of time, poop observed the sky and grouped stars into patterns or constellations. ... Boötes (IPA: Greek: herdsman) is one of the 88 modern constellations and was also one of the 48 constellations listed by Ptolemy. ... Equatorial Coordinates Right ascension (abbrev. ... In astronomy, declination (abbrev. ... The apparent magnitude (m) of a star, planet or other celestial body is a measure of its apparent brightness as seen by an observer on Earth. ... In astronomy, stellar classification is a classification of stars based initially on photospheric temperature and its associated spectral characteristics, and subsequently refined in terms of other characteristics. ... In astronomy, the color index is a simple numerical expression that determines the color of an object, which in the case of a star gives its temperature. ... In astronomy, the color index is a simple numerical expression that determines the color of an object, which in the case of a star gives its temperature. ... This article or section contains a plot summary that is overly long or excessively detailed. ... Illustration of the use of optical wavelength interferometry to determine precise positions of stars. ... Radial velocity is the velocity of an object in the direction of the line of sight. ... kilometre per second is an SI derived unit of both speed (scalar) and velocity (vector), signified by the symbol km/s or km s-1. ... The proper motion of a star is the motion of the position of the star in the sky (the change in direction in which we see it, as opposed to the radial velocity) after eliminating the improper motions of the stars, which affect their measured coordinates but are not real... A milliarcsecond (m, mas) , or a thoundsanth of an arcsecond. ... A year (from Old English gÄ“r) is the time between two recurrences of an event related to the orbit of the Earth around the Sun. ... A milliarcsecond (m, mas) , or a thoundsanth of an arcsecond. ... A year (from Old English gÄ“r) is the time between two recurrences of an event related to the orbit of the Earth around the Sun. ... For other uses, see Parallax (disambiguation). ... A milliarcsecond (m, mas) , or a thoundsanth of an arcsecond. ... Distance is a numerical description of how far apart objects are at any given moment in time. ... A light-year or lightyear (symbol: ly) is a unit of measurement of length, specifically the distance light travels in vacuum in one year. ... A parsec is the distance from the Earth to an astronomical object which has a parallax angle of one arcsecond. ... In astronomy, absolute magnitude is the apparent magnitude, m, an object would have if it were at a standard luminosity distance away from us, in the absence of interstellar extinction. ... For other uses, see Mass (disambiguation). ... In astronomy, the solar mass is a unit of mass used to express the mass of stars and larger objects such as galaxies. ... This article is about an authentication, authorization, and accounting protocol. ... In astronomy, the solar radius is a unit of length used to express the size of stars and larger objects such as galaxies. ... This article does not cite any references or sources. ... The solar luminosity, , is a unit of luminosity (power emitted in the form of photons) conventionally used by astronomers to give the luminosities of stars. ... For other uses, see Temperature (disambiguation). ... For other uses, see Kelvin (disambiguation). ... The globular cluster M80. ... This article is about the astronomical object. ... A year (from Old English gÄ“r) is the time between two recurrences of an event related to the orbit of the Earth around the Sun. ... A star catalogue, or star catalog, is an astronomical catalog that lists stars. ... The Henry Draper Catalogue is an astronomy catalogue with astrometric and spectroscopic data about more than 225,000 stars. ... In astronomy, many stars are referred to simply by catalogue numbers. ... In astronomy, many stars are referred to simply by catalogue numbers. ... In astronomy, many stars are referred to simply by catalogue numbers. ... In astronomy, many stars are referred to simply by catalogue numbers. ... In astronomy, many stars are referred to simply by catalogue numbers. ... The Hipparcos and Tycho Catalogues (Tycho-1) are the primary products of the European Space Agencys astrometric mission, Hipparcos. ... SIMBAD (the Set of Identifications, Measurements, and Bibliography for Astronomical Data) is a database of astronomical information about objects within the Milky Way. ... Alpha (uppercase Α, lowercase α) is the first letter of the Greek alphabet. ... This article is about the star grouping. ... Boötes (IPA: Greek: herdsman) is one of the 88 modern constellations and was also one of the 48 constellations listed by Ptolemy. ... Bright stars can be bright because they produce more light, because they are closer to us, or both. ... The apparent magnitude (m) of a star, planet or other heavenly body is a measure of its apparent brightness; that is, the amount of light received from the object. ... For other uses, see Sirius (disambiguation). ... Canopus (α Car / α Carinae / Alpha Carinae) is the brightest star in the southern constellation of Carina, and the second brightest star in the sky, with a visual magnitude of −0. ... Alpha Centauri (α Cen / α Centauri, also known as Rigil Kentaurus), is the brightest star system in the southern constellation of Centaurus. ... The Local Interstellar Cloud is the interstellar cloud that our solar system is currently moving through. ...

An easy way to find Arcturus is to follow the arc of the handle of the Big Dipper. By continuing in this path, one can find Spica (α Virginis) as well — leading to the coinage of the popular maxim, "Arc to Arcturus, then speed on to Spica." Big Dipper map A group of the brightest stars of the constellation Ursa Major, the Great Bear, form a well-known asterism that has been recognized as a distinct grouping in many cultures from time immemorial. ... Spica (α Vir / α Virginis / Alpha Virginis) is the brightest star in the constellation Virgo, and one of the brightest stars in the nighttime sky. ... Virgo (pronounced , Latin: , symbol , ) is a constellation of the zodiac. ... Spica (α Vir / α Virginis / Alpha Virginis) is the brightest star in the constellation Virgo, and one of the brightest stars in the nighttime sky. ...

Etymology

The name of the star derives from ancient Greek Αρκτοῦρος (Arktouros) and means "Bear Guard." This is a reference to it being the brightest star in the constellation Boötes (of which it forms the left foot), which is next to the Big and Little Bears, Ursa Major and Ursa Minor. There is also a Greek non-governmental environmental organization named Αρκτούρος that protects wild life. This article is about the constellation. ... Ursa Minor (IPA: ) is a constellation in the northern sky, the name of which means Smaller Bear in Latin. ... Environmental Centre ARCTUROS, commonly known as Arcturos, is a Greek ecological organization which focuses its efforts on saving the brown bear and its habitats. ...

In Arabic, it is called As-Simak ar-Ramih (السماك الرامح) which has been translated as "leg of the lance-bearer" or "the lofty lance-bearer." This name has been variously romanized in the past, leading to obsolete variants such as Aramec and Azimech. Another Arabic name is Al-Harith as-Sama' (الحارس السماء), "the keeper of heaven."^[1][2][3] Arabic redirects here. ... Languages can be romanized in a variety of ways, as shown here with Mandarin Chinese In linguistics, romanization (or Latinization, also spelled romanisation or Latinisation) is the representation of a word or language with the Roman (Latin) alphabet, or a system for doing so, where the original word or language...

In Chinese astronomy, Arcturus is called Dah Jyaoo (大角, Great Horn, Pinyin: Dàjiǎo), because it is the brightest star in the Chinese constellation called Jyaoo Shiuh (角宿, Pinyin: Jiǎo Xiǔ). And later, it become a part of Kangh Shiuh (亢宿, Pinyin: Kàng Xiǔ), which is also a Chinese constellation. This article or section is in need of attention from an expert on the subject. ... Pinyin, more formally called Hanyu Pinyin (Simplified Chinese: ; Traditional Chinese: ; Pinyin: ), is the most common variant of Standard Mandarin romanization system in use. ... Chinese constellations are different from the western constellations, due to the independent development of ancient Chinese astronomy. ... Horn Mansion (角宿) is a constellation in Chinese astronomy. ...

Ancient Japanese astronomy adopted the Chinese name Dah Jyaoo (大角, Tai Roku), but its western name, Arcturus (アルクトゥルス), is more common now.^{[citation needed]}

It corresponds to the Hindu astronomy Nakshatra of Svātī. A page from the Hindu calendar 1871-72. ... A nakshatra (Devanagari: नक्षत्र) or lunar mansion is one of the 27 or 28 divisions of the sky, identified by the prominent star(s) in them, that the Moon passes through during its monthly cycle, as used in Hindu astronomy and astrology. ... Svati (pronounced SvātÄ«, with a lengthened a and i) is a Nakshatra in Hindu astronomy, that corresponds to the star Arcturus. ...

Stellar system

Arcturus is a type K1.5 IIIpe red giant star — the letters "pe" stand for "peculiar emission," which indicates that the spectrum of light given off by the star is unusual and full of emission lines. This is not too uncommon in red giants, but Arcturus has a particularly strong case of the phenomenon. It is at least 110 times more luminous than the Sun, but this underestimates its strength as much of the "light" it gives off is in the infrared; total power output is about 180 times that of the Sun. The lower output in visible light is due to a lower efficacy as the star has a lower surface temperature than the Sun. In astronomy, stellar classification is a classification of stars based initially on photospheric temperature and its associated spectral characteristics, and subsequently refined in terms of other characteristics. ... According to the Hertzsprung-Russell diagram, a red giant is a large non-main sequence star of stellar classification K or M; so-named because of the reddish appearance of the cooler giant stars. ... Legend γ = Gamma rays HX = Hard X-rays SX = Soft X-Rays EUV = Extreme ultraviolet NUV = Near ultraviolet Visible light NIR = Near infrared MIR = Moderate infrared FIR = Far infrared Radio waves EHF = Extremely high frequency (Microwaves) SHF = Super high frequency (Microwaves) UHF = Ultra high frequency VHF = Very high frequency HF = High... This article does not cite any references or sources. ... A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from an excess or deficiency of photons in a narrow frequency range, compared with the nearby frequencies. ... Sol redirects here. ... For other uses, see Infrared (disambiguation). ... Luminous efficacy is a property of light sources, which indicates what portion of the emitted electromagnetic radiation is usable for human vision. ...

Arcturus is notable for its high proper motion, larger than any first magnitude star in the stellar neighborhood other than α Centauri. It is now almost ^[4] at its closest point to the Sun, and is moving rapidly (122 km/s) relative to the solar system. Arcturus is thought to be an old disk star, and appears to be moving with a group of 52 other such stars. Its mass is hard to exactly determine, but may be about the same as the Sun, and is no more than 1.5 solar masses. Arcturus is likely to be considerably older than the Sun, and much like what the Sun will be in its red giant phase. Alpha Centauri (α Cen / α Centauri, also known as Rigil Kentaurus), is the brightest star system in the southern constellation of Centaurus. ...

Arcturus' size relative to the Sun

According to the Hipparcos satellite, Arcturus is 36.7 light years (11.3 parsecs) from Earth, relatively close in astronomical terms. Hipparcos also suggested that Arcturus is a binary star, with the companion about twenty times dimmer than the primary and orbiting close enough to be at the very limits of our current ability to make it out. The most recent studies of the issue are generally coming down on the side of it being a single star, however.^[5] Image File history File links Arcturus-star. ... Image File history File links Arcturus-star. ... Hipparcos (for High Precision Parallax Collecting Satellite) was an astrometry mission of the European Space Agency (ESA) dedicated to the measurement of stellar parallax and the proper motions of stars. ... A light-year or lightyear (symbol: ly) is a unit of measurement of length, specifically the distance light travels in vacuum in one year. ... A parsec is the distance from the Earth to an astronomical object which has a parallax angle of one arcsecond. ... This article is about Earth as a planet. ... For the band of the same name, see: Binary Star (band) Hubble image of the Sirius binary system, in which Sirius B can be clearly distinguished (lower left). ...

Seismology

As one of the brightest stars in the sky, Arcturus has been the subject of a number of studies in the emerging field of astroseismology.

Belmonte et al. (1990) carried out a radial velocity (Doppler shift of spectral lines) study of the star in April and May 1988, which showed variability with a frequency of the order of a few microhertz, the highest peak corresponding to 4.3 μHz (2.7 days) with an amplitude of 60 ms^-1, with a frequency separation of ~5 μHz. They suggested that the most plausible explanation for the variability of Arcuturus is stellar oscillations. The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ...

High precision photometry from the Hipparcos satellite's observations showed Arcturus is now known to be slightly variable, by about 0.04 magnitudes over 8.3 days.^{[citation needed]} It is believed that the surface of the star oscillates slightly, a common feature of red giant stars. In the case of Arcturus, this was an interesting discovery as it is known that the redder (more towards or within the M spectral class) a giant gets, the more variable it will be. Extreme cases like Mira undergo large swings over hundreds of days; Arcturus is not very red and is a borderline case between variability and stability with its short period and tiny range. This article or section contains a plot summary that is overly long or excessively detailed. ... Chandra X-ray Image of Mira Mira (ο Cet / 68 Ceti / HD14386 / HIP10826 / ADS 1778 AP / Omicron Ceti) is a binary star in the constellation Cetus consisting of the red giant, Mira A or just Mira, and a white dwarf, Mira B or VZ Ceti. ...

Cultural significance

Comparison between the Arcturus, red supergiant Antares, and the Sun. The black circle is the size of the orbit of Mars.

Image File history File links Redgiants. ... Image File history File links Redgiants. ... This article or section does not cite its references or sources. ...

Ancient Greece

In Greek mythology, Arcturus is a star created by Zeus to protect the nearby constellations, Arcas and Callisto (Ursa major and Ursa minor). According to the ancient Greek myth, Callisto was the daughter of Lycaon, the king of Arcadia. As a young girl, she vowed to the goddess Artemis to be forever faithful and devoted to her. She was to remain a virgin forever in order to serve and accompany her while hunting animals in the forest. However, one day, Zeus, the father of the gods fell in love with Callisto and forced her to have sexual intercourse with him. Callisto gave birth to a son whom she named Arcas. Zeus knew that if Hera, his wife, learned of his disloyalty she would be angry with Callisto, so in order to protect her he transformed her into a brown bear. Callisto, as a bear, roamed around the forest looking for her son, Arcadian. After years of searching she found Arcas who was now a grown man. She finally ran into him and happy as she was she stood on her back legs and tried to embrace him. Arcas however did not recognize her and thought he was being attacked, so he drew his sword trying to defend himself. Zeus, watching everything, as usual, felt sorry for them and in order to prevent this tragedy he transformed them into constellations (Ursa major and Ursa minor) and placed them near to him in the sky. Hera, who was still furious, asked the Ocean, the river that surrounds the earth, not to permit them to wash themselves in his waters; therefore these two constellations are always seen high in the night sky. Moreover in order to protect them from Hera's jealousy he placed another star near to them, called Arcturus, which means the guardian of Arctos, the bear. It protects and accompanies them for eternity. For other uses, see Zeus (disambiguation). ... This article is about the constellation. ... Ursa Minor (IPA: ) is a constellation in the northern sky, the name of which means Smaller Bear in Latin. ...

Polynesia

Prehistoric Polynesian navigators knew Arcturus as Hokule'a, the "Star of Joy." Arcturus is the Zenith Star of the Hawaiian Islands. Using Hokule'a and other stars, the Polynesians launched their double-hulled canoes from Tahiti and the Marquesas Islands. Traveling east and north they eventually crossed the equator and reached the latitude where Arcturus would appear directly overhead in the summer night sky. Knowing they had arrived at the exact latitude of the island chain, they sailed due west on the trade winds until making landfall. If Hokule'a could be kept directly overhead, they landed on the southeastern shores of the Big Island of Hawaii. For a return trip to Tahiti the navigators could use Sirius, the zenith star of that island. Carving from the ridgepole of a Māori house, ca 1840 Polynesia (from Greek: πολύς many, νῆσος island) is a large grouping of over 1,000 islands scattered over the central and southern Pacific Ocean. ... Table of geography, hydrography, and navigation, from the 1728 Cyclopaedia. ... HōkÅ«leÊ»a is a full-scale replica of a wooden sailing vessel (Polynesian voyaging canoe) used in ancient HawaiÊ»i. ... Map of the Hawaiian Islands, a chain of islands that stretches 2,400 km in a northwesterly direction from the southern tip of the Island of Hawai‘i. ... It has been suggested that Canadian canoe be merged into this article or section. ... Tahiti is the largest island in the Windward group of the French Polynesia, located in the archipelago of Society Islands in the southern Pacific Ocean. ... National motto: Mau‘u‘u ha‘e iti Official languages French, Tahitian Political status Dependent territory, administrative division of French Polynesia Capital Tai o Hae Largest City Tai o Hae Area 1,274 km² ( 492 sq. ... World map showing the equator in red In tourist areas, the equator is often marked on the sides of roads The equator marked as it crosses Ilhéu das Rolas, in São Tomé and Príncipe. ... This article is about the geographical term. ... Amateur astronomy, often called back yard astronomy, is a hobby whose participants enjoy observing celestial objects. ... Image:Atmospheric circulatlion. ... The Island of Hawaii (called the Big Island or Hawaii Island) is a volcanic island in the Pacific Ocean and one of the eight main islands that comprise the U.S. state of Hawaii. ... Official language(s) English, Hawaiian Capital Honolulu Largest city Honolulu Area  Ranked 43rd  - Total 10,931 sq mi (29,311 km²)  - Width n/a miles (n/a km)  - Length 1,522 miles (2,450 km)  - % water 41. ... For other uses, see Sirius (disambiguation). ...

1933 World's Fair

The star achieved fame when its light was used to open the 1933 Chicago World's Fair. The star was chosen as it was thought that light from Arcturus had started its journey at about the time of the previous Chicago World's Fair in 1893. Technically the star is 36.7 light years away so the light would have started its journey in 1896. A 1933 Century of Progress worlds fair poster The Century of Progress International Exposition was a Worlds Fair held in Chicago, Illinois from 1933-1934 to celebrate Chicagos centennial. ... One-third scale replica of Daniel Chester Frenchs Republic, which stood in the great basin at the exposition, Chicago, 2004 The Worlds Columbian Exposition (also called The Chicago Worlds Fair), a Worlds Fair, was held in Chicago in 1893, to celebrate the 400th anniversary of Christopher... Year 1893 (MDCCCXCIII) was a common year starting on Sunday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Tuesday of the 12-day slower Julian calendar). ... Year 1896 (MDCCCXCVI) was a leap year starting on Wednesday (link will display calendar). ...

Edgar Cayce

In a reading in which the 'sleeping prophet' describes philosophical concepts as they relate to religious tenets, Edgar Cayce mentions Arcturus. Edgar Cayce (March 18, 1877 – January 3, 1945) (pronounced or like Casey) was an American who claimed psychic abilities. ...

(Q) The sixth problem concerns interplanetary and inter-system dwelling, between earthly lives. It was given through this source that the entity Edgar Cayce, after the experience as Uhjltd, went to the system of Arcturus, and then returned to earth. Does this indicate a usual or an unusual step in soul evolution?

(A) As indicated, or as has been indicated in other sources besides this as respecting this very problem, - Arcturus is that which may be called the center of this universe, through which individuals pass and at which period there comes the choice of the individual as to whether it is to return to complete there - that is, in this planetary system, our sun, the earth sun and its planetary system - or to pass on to others. This was an unusual step, and yet a usual one. (5749-14)

Biblical

In the King James Version of the Bible, Arcturus is mentioned twice in the Book of Job: This page is about the version of the Bible; for the Harvey Danger album, see King James Version (album). ... This Gutenberg Bible is displayed by the United States Library. ... The Book of Job (איוב) is one of the books of the Hebrew Bible. ...

"Which maketh Arcturus, Orion, and Pleiades, and the chambers of the south."

Job 9:9

"Canst thou bring forth Mazzaroth in his season?

or canst thou guide Arcturus with his sons?"

Job 38:32

The Hebrew word thus translated is עיש Ash or 'Ayish. Due to the obscurity of ancient terminology, some scholars dispute this identification, instead equating it with Aldebaran, Canopus, Ursa Major, or the Pleiades, among other celestial objects.^[6] Orion (IPA: ), a constellation often referred to as The Hunter, is a prominent constellation, one of the largest and perhaps the best-known and most conspicuous in the sky[1]. Its brilliant stars are found on the celestial equator and are visible throughout the world, making this constellation globally recognized. ... The Pleiades, also called Open cluster M45, visible from both the northern and southern hemispheres, consists of many bright, hot stars that were all formed at the same time within a large cloud of interstellar dust and gas. ... The word Mazzaroth is mentioned only once in the King James Version of the Old Testament of the Bible: it is found in the Book of Job 38:32 It raises several issues: 1. ... “Hebrew” redirects here. ... Aldebaran from the Arabic (الدبران al-dabarān) meaning the follower, (α Tau / α Tauri / Alpha Tauri) is the brightest star in the constellation Taurus and one of the brightest stars in the nighttime sky. ... Canopus (α Car / α Carinae / Alpha Carinae) is the brightest star in the southern constellation of Carina, and the second brightest star in the sky, with a visual magnitude of −0. ...

Occult traditions

In the astrology of the Middle Ages, Arcturus was one of the 15 Behenian fixed stars, associated with jasper and the plantain herb. Cornelius Agrippa lists its symbol under the alternate name Alchameth. Hand-coloured version of the anonymous Flammarion woodcut (1888). ... The Middle Ages formed the middle period in a traditional schematic division of European history into three ages: the classical civilization of Antiquity, the Middle Ages, and modern times, beginning with the Renaissance. ... List of Behenian Stars Caput Algol (Algols head, associated with the head of Gorgona), Pleiades (actually, several stars), Aldebaran, Alhayhoch, Canis Maior (actually, a constellation, like the next one), Canis Minor, Cor Leonis (Hearth of the Lion), Cauda Urse (Tail of the Bear), Ala Corvi (Wing of the crow... Polished jasper pebble, one inch (2. ... Subgenus There are 5 subgenera in Plantago. ... Cornelius Agrippa, as portrayed in Libri tres de occulta philosophia Heinrich Cornelius Agrippa von Nettesheim (born in Köln September 14, 1486 - died in Grenoble February 18, 1535) was a magician and occult writer, astrologer, and alchemist. ... Image File history File links after Agrippa File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...

See also

• Arcturus in fiction
• Arcturus stream

The planetary systems of stars other than the Sun and its Solar System are a staple element in much science fiction. ... In astronomy, the Arcturus Stream is a stream of stars, including the nearby bright star Arcturus which share similar proper motion. ...

References

1. ^ List of the 25 brightest stars, website of the Jordanian Astronomical Society, accessed March 28, 2007.
2. ^ Richard Hinckley Allen, Star-names and their meanings (1936), p. 100-101.
3. ^ Hans Wehr (J.M. Cowan ed.), A dictionary of modern written Arabic (1994).
4. ^ "Almost" on an astronomical timescale. Closest approach will happen in about 4000 years, at a distance of 99.9% the current distance.
5. ^ Anonymous (2007). Arcturus. SolStation Co.. Retrieved on 2007-06-01.
6. ^ Hirsch, Emil G. (1906). Constellations. In The Jewish Encyclopedia. New York: Funk & Wagnall's. Retrieved July 11, 2005.

Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 152nd day of the year (153rd in leap years) in the Gregorian calendar. ...

External links

• Illustration comparing the size of Arcturus with other stars
• SolStation.com entry