This system consists of a spectral class B3 star being orbited by a less massive class A4 star. The plane of their orbit lies almost along the line of sight to the Earth. Every 3.953 days the system temporarily decreases in brightness by 1.1 magnitudes as the brighter star is partially eclipsed by the dimmer companion. Sony VAIO VGN-SR290JTJ Battery
The two stars are separated by only 0.1 astronomical units, so their shapes are modified by mutual tidal interaction. This results in a variation of their net magnitude throughout each orbit.[29]
Located about 1.8° west of Epsilon (ε) Tauri is T Tauri, the prototype of a class of variable stars called T Tauri stars. Sony VAIO VGN-SR290JTQ Battery
This star undergoes erratic changes in luminosity, varying between magnitude 9 to 13 over a period of weeks or months.[5] This is a newly formed stellar object that is just emerging from its envelope of gas and dust, but has not yet become a main sequence star.[30] The surrounding reflection nebula NGC 1555 is illuminated by T Tauri, and thus is also variable in luminosity.[31] Sony VAIO VGN-SR290JVB/C Battery
This constellation includes part of the Taurus-Auriga complex, or Taurus dark clouds, a star forming region of sparse, filamentary clouds. This spans a diameter of 98 light-years (30 parsecs) and contains 35,000 solar masses of material, which is both larger and less massive than the Orion Nebula.[32] Sony VAIO VGN-SR290JVH/C Battery
At a distance of 490 light-years (150 parsecs), this is one of the nearest active star forming regions.[33] Located in this region, about 10° to the northeast of Aldebaran, is an open cluster NGC 1746 spanning a width of 45 arcminutes.The identification of the constellation of Taurus with a bull is very old, certainly dating to the Chalcolithic, and perhaps even to the Upper Paleolithic.Sony VAIO VGN-SR290NTB Battery
Michael Rappenglück of the University of Munich believes that Taurus is represented in a cave painting at the Hall of the Bulls in the caves at Lascaux (dated to roughly 15,000 BC), which he believes is accompanied by a depiction of the Pleiades. The name "seven sisters" has been used for the Pleiades in the languages of many cultures, including indigenous groups of Australia, North America and Siberia. Sony VAIO VGN-SR29VN/S Battery
This suggests that the name may have a common ancient origin.[36]
Taurus marked the point of vernal (spring) equinox in the Chalcolithic and the Early Bronze Age (the "Age of Taurus"), from about 4000 BC to 1700 BC, after which it moved into the neighboring constellation Aries.[37] Sony VAIO VGN-SR29XN/S Battery
The Pleiades were closest to the Sun at vernal equinox around the 23rd century BC. In Babylonian astronomy, the constellation was listed in the MUL.APIN as GU4.AN.NA, "The Heavenly Bull".[38] As this constellation marked the vernal equinox, it was also the first constellation in the Babylonian zodiac and they described it as "The Bull in Front".[39] The Akkadian name wasAlu.[40]Sony VAIO VGN-SR2RVN/S Battery
In the Mesopotamian Epic of Gilgamesh, one of the earliest works of literature, the goddess Ishtar sends Taurus, the Bull of Heaven, to kill Gilgamesh for spurning her advances.[41] Gilgamesh is depicted as the neighboring constellation of Orion, and in the sky they face each other as if engaged in combat.[42] Sony VAIO VGN-SR390NAB Battery
In early Mesopotamian art, the Bull of Heaven was closely associated with Inanna, the Sumerian goddess of sexual love, fertility, and warfare. One of the oldest depictions shows the bull standing before the goddess' standard; since it has 3 stars depicted on its back (the cuneiform sign for "star-constellation"), there is good reason to regard this as the constellation later known as Taurus.[40] Sony VAIO VGN-SR390NAH Battery
The same iconic representation of the Heavenly Bull was depicted in the Dendera zodiac, an Egyptian bas-relief carving in a ceiling that depicted the celestial hemisphere using a planisphere. In these ancient cultures, the orientation of the horns was portrayed as upward or backward. Sony VAIO VGN-SR41M/P Battery
This differed from the later Greek depiction where the horns pointed forward.[43] To the Egyptians, the constellation Taurus was a sacred bull that was associated with the renewal of life in spring. When the spring equinox entered Taurus, the constellation would become covered by the Sun in the western sky as spring began. Sony VAIO VGN-SR41M/S Battery
This "sacrifice" led to the renewal of the land.[44] To the early Hebrews, Taurus was the first constellation in their zodiac and consequently it was represented by the first letter in their alphabet, Aleph.[45]
In Greek mythology, Taurus was identified with Zeus, who assumed the form of a magnificent white bull to abduct Europa, a legendary Phoenician princess. Sony VAIO VGN-SR49VN/H Battery
In illustrations of Greek mythology, only the front portion of this constellation are depicted; this was sometimes explained as Taurus being partly submerged as he carried Europa out to sea. A second Greek myth portrays Taurus as Io, a mistress of Zeus. To hide his lover from his wife Hera, Zeus changed Io into the form of a heifer.[46] Sony VAIO VGN-SR51B/P Battery
Greek mythographer Acusilaus marks the bull Taurus as the same that formed the myth of the Cretan Bull, one of The Twelve Labors of Heracles.[47]
Taurus became an important object of worship among the Druids. Their Tauric religious festival was held while the Sun passed through the constellation.[37] Sony VAIO VGN-SR51B/S Battery
In Buddhism, legends hold that Gautama Buddha was born when the Full Moon was inVaisakha, or Taurus.[48] Buddha's birthday is celebrated with the Wesak Festival, or Vesākha, which occurs on the first or second Full Moon when the Sun is in Taurus.
Gemini is one of the constellations of the zodiac. Sony VAIO VGN-SR51MF Battery
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 symbol is (Unicode ♊).Sony VAIO VGN-SR51MF/P Battery
Gemini lies between Taurus to the west and Cancer to the east, with Aurigaand Lynx to the north and Monoceros and Canis Minor to the south.
The Sun resides in the astrological sign of Gemini from 21 June to 21 July each year. By mid August, Gemini will appear along the eastern horizon in the morning sky prior to sunrise. Sony VAIO VGN-SR51MF/S Battery
The best time to observe Gemini at night is overhead during the months of January and February. By April and May, the constellation will be visible soon after sunset in the west.
The easiest way to locate the constellation is to find its two brightest stars Castor and Pollux eastward from the familiar “V” shaped asterism ofTaurus and the three stars of Orion’s belt. Sony VAIO VGN-SR51MF/W Battery
Another way is to mentally draw a line from the Pleiades star cluster located in Taurus and the brightest star in Leo, Regulus. In doing so, you are drawing an imaginary line that is relatively close to the ecliptic, a line which intersects Gemini roughly at the midpoint of the constellation, just below Castor and Pollux. Sony VAIO VGN-SR51MR Battery
The brightest stars in Gemini are Castor and Pollux. Although Castor has the Bayer designation "Alpha," it is actually the second brightest in the constellation after Pollux. Castor is a sextuple star system 52 light-years from Earth, which appears as a magnitude 1.6 blue-white star to the unaided eye. Sony VAIO VGN-SR59VG Battery
Two spectroscopic binaries are visible at magnitudes 1.9 and 3.0 with a period of 470 years. A wide-set red dwarf star is also a part of the system; this star is an Algol-typeeclipsing binary star with a period of 19.5 hours; its minimum magnitude is 9.8 and its maximum magnitude is 9.3. Sony VAIO VGN-SR59VG/H Battery
Beta Geminorum, named for Pollux, is, despite its designation, the brightest star in Gemini. It is an orange-hued giant starof magnitude 1.2, 34 light-years from Earth. The discrepancy in brightness and designation with Castor and Pollux is attributable to a mistake by Johann Bayer, who gave his eponymous designations in 1603.[4] Sony VAIO VGN-SR70B/S Battery
There are several other bright stars, including multiple stars, in Gemini. Gamma Geminorum, called Alhena, is a blue-white hued star of magnitude 1.9, 105 light-years from earth. Delta Geminorum, traditionally named Wasat, is a long-period binary star 59 light-years from Earth. Sony VAIO VGN-SR72B/P Battery
The primary is a white star of magnitude 3.5, and the secondary is anorange dwarf star of magnitude 8.2. The period is over 1000 years; it is divisible in medium amateur telescopes. Epsilon Geminorum is a double star. The primary is a yellow supergiant of magnitude 3.1, 900 light-years from Earth. Sony VAIO VGN-SR72B/S Battery
The optical companion, of magnitude 9.2, is visible in binoculars and small telescopes.[4]
Zeta Geminorum is a double star. The primary is a Cepheid variable star with a period of 10.2 days; its minimum magnitude is 4.2 and its maximum magnitude is 3.6. It is a yellow supergiant, 1200 light-years from Earth. Sony VAIO VGN-SR73JB/S Battery
The companion, a magnitude 7.6 star, is visible in binoculars and small amateur telescopes. Eta Geminorum is a binary star with a variable component. 350 light-years away, it has a period of 500 years and is only divisible in large amateur telescopes. The primary is a semi-regular red giant with a period of 233 days; Sony VAIO VGN-SR74FB/S Battery
its minimum magnitude is 3.9 and its maximum magnitude is 3.1. The secondary is of magnitude 6.Kappa Geminorum is a binary star 143 light-years from Earth. The primary is a yellow giant of magnitude 3.6; the secondary is of magnitude 8. The two are only divisible in larger amateur instruments because of the discrepancy in brightness. Sony VAIO VGN-SR90FS Battery
Nu Geminorum is a double star divisible in binoculars and small amateur telescopes. The primary is a blue giant of magnitude 4.1, 500 light-years from Earth, and the secondary is of magnitude 8. 38 Geminorum is a binary star divisible in small amateur telescopes, 91 light-years from Earth. Sony VAIO VGN-SR90NS Battery
The primary is a white star of magnitude 4.8 and the secondary is a yellow star of magnitude 7.8.Pollux has an extrasolar planet revolving around it, as do two other stars in Gemini, HD 50554, and HD 59686. Another noteworthy star is Mekbuda (ζ Gem), a supergiant with a radius that is 60 times solar, making it approximately 220,000 times the size of the Sun. Sony VAIO VGN-SR90S Battery
U Geminorum is a dwarf nova type cataclysmic variable discovered by J.R. Hind in 1855.
To look at Gemini is to look away from the Milky Way; as a result, there are comparatively few deep-sky objects of note. TheEskimo Nebula and Medusa Nebula, Messier object M35, and Geminga are those that attract the most attention. Sony VAIO VGN-SR90US Battery
The Eskimo and Medusa nebulae are both planetary nebulae, the one approximately 2,870 light years away and the other 1,500 light years distant. M35 is an open star cluster which was discovered in the year 1745 by Swiss astronomer Philippe Loys de Chéseaux. And Geminga is a neutron star approximately 550 light years from Earth. Sony VAIO VGN-SR91NS Battery
Other objects of note are NGC 2129, NGC 2158, NGC 2266, NGC 2331, NGC 2355, and NGC 2395.M35 (NGC 2168) is a large, elongated open cluster of magnitude 5; it has an area of approximately 0.2 square degrees, the same size as the full Moon. Its high magnitude means that M35 is visible to the unaided eye under dark skies; under brighter skies it is discernible in binoculars. Sony VAIO VGN-SR91PS Battery
The 200 stars of M35 are arranged in chains that curve throughout the cluster; it is 2800 light-years from Earth. Another open cluster in Gemini is NGC 2158. Visible in large amateur telescopes and very rich, it is more than 12,000 light-years from Earth.[4]Sony VAIO VGN-SR91S Battery
The Eskimo Nebula or Clown Face Nebula (NGC 2392) is a planetary nebula with an overall magnitude of 9.2, located 4000 light-years from Earth.[6] In a small amateur telescope, its 10th magnitude central star is visible, along with its blue-green elliptical disk. It is named for its resemblance to the head of a person wearing a parka. Sony VAIO VGN-SR91US Battery
The Geminids are a prominent, bright meteor shower that peaks on December 13–14. It has a maximum rate of approximately 100 meteors per hour, making it one of the richest meteor showers.[4] The Epsilon Geminids peak between October 18 and October 29 and have only been recently confirmed. Sony VAIO VGN-SR92NS Battery
They overlap with the Orionids, which make the Epsilon Geminids difficult to detect visually. Epsilon Geminid meteors have a higher velocity than Orionids.
In Babylonian astronomy, the stars Castor and Pollux were known as the Great Twins (MUL.MASH.TAB.BA.GAL.GAL). Sony VAIO VGN-SR92PS Battery
The Twins were regarded as minor gods and were called Meshlamtaea and Lugalirra, meaning respectively 'The One who has arisen from the Underworld' and the 'Mighty King'. Both names can be understood as titles of Nergal, the major Babylonian god of plague and pestilence, who was king of the Underworld.[8] Sony VAIO VGN-SR92S Battery
In Greek mythology, Gemini was associated with the myth of Castor and Pollux, the children of Leda and Argonautsboth. Pollux was the son of Zeus, who seduced Leda, while Castor was the son of Tyndareus, king of Sparta and Leda's husband. Castor and Pollux were also mythologically associated with St. Elmo's fire in their role as the protectors of sailors. Sony VAIO VGN-SR92US Battery
When Castor died, because he was mortal, Pollux begged his father Zeus to give Castor immortality, and he did, by uniting them together in the heavens.
The constellation contains 85 stars visible to observation on Earth without a telescope. Sony VAIO VGN-SR93DS Battery
Gemini is dominated by Castor and Pollux, two bright stars that appear relatively close together, encouraging the mythological link between the constellation and twinship. The twin above and to the right (as seem from the Northern Hemisphere) is Castor, whose brightest star is α Geminorum (more commonly called Castor); Sony VAIO VGN-SR93JS Battery
it is a second magnitude star and represents Castor's head. The twin below and to the left is Pollux, whose brightest star is β Geminorum(more commonly called Pollux); it is of the first magnitude and represents Pollux's head. Furthermore, the other stars can be visualized as two parallel lines descending from the two main stars, making it look like two figures. Sony VAIO VGN-SR93PS Battery
H.A. Rey has suggested an alternative to the traditional visualization that connected the stars of Gemini to show twins holding hands. Pollux's torso is represented by the star υ Geminorum, Pollux's right hand by ι Geminorum, Pollux's left hand by κ Geminorum; all three of these stars are of the fourth magnitude. Sony VAIO VGN-SR93YS Battery
Pollux's pelvis is represented by the star δ Geminorum, Pollux's right knee by ζ Geminorum, Pollux's right foot by γ Geminorum, Pollux's left knee by λ Geminorum, and Pollux's left foot by ξ Geminorum. Gamma Geminorum is of the second magnitude, while Delta and Xi Geminorum are of the third magnitude. Sony VAIO VGN-SR94FS Battery
Castor's torso is represented by the star τ Geminorum, Castor's left hand by ι Geminorum (which he shares with Pollux), Castor's right hand by θ Geminorum; all three of these stars are of the fourth magnitude. Castor's pelvis is represented by the star ε Geminorum, Sony VAIO VGN-SR94GS Battery
Castor's left foot by ν Geminorum, and Castor's right foot by μ Geminorum and η Geminorum; ε, μ, and η Geminorum are of the third magnitude. The brightest star in this constellation is Pollux.
In Meteorologica (1 343b30) Aristotle mentions that he observed Jupiter in conjunction with and then occulting a star in Gemini.Sony VAIO VGN-SR94HS Battery
This is the earliest known observation of this nature.[11] A study published in 1990 suggests the star involved was 1 Geminorum and the event took place on 5 December 337 BC.[12]
When William Herschel discovered Uranus on 13 March 1781 it was located near Eta Geminorum.[13] Sony VAIO VGN-SR94VS Battery
In 1930 Clyde Tombaugh exposed a series of photographic platescentred on Delta Geminorum and discovered Pluto.
Cancer is one of the twelve constellations of the zodiac. Its name is Latin for crab and it is commonly represented as such. Its astrological symbol is (Unicode ♋).Sony VAIO VPC CW2MFX/PU Battery
Cancer is relatively small among the constellations with an area of only 505 square degrees and its stars are rather faint. It lies between Gemini to the west and Leo to the east, Lynx to the north and Canis Minor and Hydra to the south.
Cancer is the dimmest of the zodiacal constellations, having only two stars above the fourth magnitude.[1] Sony VAIO VPC S11V9E/B Battery
α Cnc (Acubens) is a double star with a primary of magnitude 4.3, 173 light-years from Earth. The secondary is of magnitude 12.0 and is visible in small amateur telescopes. Its common name means "the claw".[1]
β Cnc (Altarf) is the brightest star in Cancer at magnitude 3.5. Sony VAIO VPCB119GJ/B Battery
It is an orange-hued binary star system consisting of a K-type orange giant and a red dwarf located 290 light-years from Earth. Altarf represents a part of Cancer's body. [1]
γ Cnc (Asellus Borealis) is a white-hued star of magnitude 4.7, 158 light-years from Earth. Its common name means "northern donkey".[1] Sony VAIO VPCB11AGJ Battery
δ Cnc (Asellus Australis) is an orange-hued giant star of magnitude 3.9, 136 light-years from Earth. Its common name means "southern donkey".[1]
ζ Cnc is a multiple star system 83 light-years from Earth. The two brightest components are a binary star with an orbital period of 1100 years; Sony VAIO VPCB11AVJ Battery
the brighter component is a yellow-hued star of magnitude 70000.0 and the dimmer component is a yellow-hued star of magnitude 6.2. The brighter component is itself a binary star with a period of 59.5 years; its primary is of magnitude 5.6 and its secondary is of magnitude 6.0. This pair will be at its greatest separation in 2018.[1] Sony VAIO VPCB11V9E Battery
ι Cnc is a wide double star. The primary is a yellow-hued giant star of magnitude 4.0, 298 light-years from Earth. The secondary is a blue-white hued star of magnitude 6.6.[1]
55 Cnc has a quintuple planet system with one super-earth and four gas giants, one of which is in the habitable zoneand as of such has expected temperatures similar to Earth. Sony VAIO VPCB11X9E Battery
Cancer is best known among stargazers as the home of Praesepe (Messier 44), an open cluster also called the Beehive Cluster, 577 light-years from Earth. M44 contains about 50 stars, the brightest of which are of the sixth magnitude. ε Cnc is the brightest member at magnitude 6.3. Sony VAIO VPCCW18FJ/P Battery
Praesepe is also one of the larger open clusters visible; it has an area of 1.5 square degrees, or three times the size of the full Moon.[1]
The smaller, denser open cluster Messier 67 can also be found in Cancer, 2500 light-years from Earth. It has an area of approximately 0.5 square degrees, the size of the full Moon. Sony VAIO VPCCW18FJ/R Battery
It contains approximately 200 stars, the brightest of which are of the tenth magnitude.
Cancer is said to have been the place for the Akkadian Sun of the South, perhaps from its position at the summer solstice in very remote antiquity. But afterwards it was associated with the fourth month Duzu (June–July in the modern western calendar), and was known as the Northern Gate of Sun. Sony VAIO VPCCW18FJ/W Battery
Showing but few stars, and its brightest stars being of only 4th magnitude,[1] Cancer was often considered the "Dark Sign", quaintly described as black and without eyes.
Cancer was the location of the Sun's most northerly position in the sky (the summer solstice) in ancient times, though this position now occurs in Taurus due to the precession of the equinoxes, around June 21. Sony VAIO VPCCW19FJ/W Battery
This is also the time that the sun is directly overhead at 23.5°N, a parallel now known as the Tropic of Cancer.
The modern symbol for Cancer represents the pincers of a crab, but Cancer has been represented as various types of creatures, usually those living in the water, and always those with an exoskeleton. Sony VAIO VPCCW1AFJ Battery
In the Egyptian records of about 2000 BC it was described as Scarabaeus (Scarab), the sacred emblem of immortality. In Babylonia the constellation was known as MUL.AL.LUL, a name which can refer to both a crab and a snapping turtle. On boundary stones, Sony VAIO VPCCW1AHJ Battery
the image of a turtle or tortoise appears quite regularly and it is believed that this represent Cancer as a conventional crab has not so far been discovered on any of these monuments. There also appears to be a strong connection between the Babylonian constellation and ideas of death and a passage to the underworld, Sony VAIO VPCCW1S1E Battery
which may be the origin of these ideas in much later Greek myths associated with Hercules and the Hydra.[2] In the 12th century, an illustrated astronomical manuscript shows it as a water beetle. Albumasar writes of this sign in the work published in 1489 as a large crayfish. Sony VAIO VPCCW1S1E/B Battery
Jakob Bartsch and Stanislaus Lubienitzki, in the 17th century, described it as a lobster.
In Ancient Greece, Aratus called the crab Καρκινος (Karkinos), which was followed by Hipparchus and Ptolemy. TheAlfonsine tables called it Carcinus, a Latinized form of the Greek word. Eratosthenes extended this as Καρκινος,Ονοι, και Φατνη: the Crab, Asses, and Crib. Sony VAIO VPCCW1S1E/L Battery
The Indian language Sanskrit shares a common ancestor with Greek, and the Sanskrit name of Cancer is Karka and Karkata. InTelugu it is "Karkatakam", in Kannada "Karkataka" or "Kataka", in Tamil Karkatan, and in Sinhalese Kagthaca. The later Hindus knew it as Kulira, from the GreekΚολουρος (Koloyros), the term originated by Proclus. Sony VAIO VPCCW1S1E/P Battery
In Ancient Rome, Manilius and Ovid called the constellation Litoreus (shore-inhabiting). Astacus and Cammarus appear in various classic writers, while it is called Nepa in Cicero's De Finibus and the works of Columella, Plautus, and Varro; all of these words signify crab, lobster, or scorpion. Sony VAIO VPCCW1S1E/R Battery
Athanasius Kircher said that in Coptic Egypt it was Κλαρια, the Bestia seu Statio Typhonis (the Power of Darkness). Jérôme Lalande identified this withAnubis[citation needed], one of the Egyptian divinities commonly associated with Sirius.
The creation of the constellation is explained in Greek mythology by the short-lived association of Karkinos with one of theTwelve Labors of Hercules, Sony VAIO VPCCW1S1E/W Battery
in which Hercules battled the multi-headed Lernaean Hydra. Hera had sent Karkinos to distract Hercules and put him at a disadvantage during the battle, but Hercules quickly dispatched the creature by kicking it with such force that it was propelled into the sky. Sony VAIO VPCCW21FX/B Battery
Other accounts had Karkinos grabbing onto Hercules' toe with its claws, but Hercules simply crushed the crab underfoot. Hera, grateful for Karkinos' heroic effort, gave it a place in the sky.[1] Some scholars have suggested that Karkinos was a late addition to the myth of Hercules in order to make the Twelve Labors correspond to the twelve signs of the Zodiac. Sony VAIO VPCCW21FX/L Battery
As of 2002, the Sun appears in the constellation Cancer from July 21 to August 9. In tropical astrology, the Sun is considered to be in the sign Cancer from June 21 to July 21, and in sidereal astrology, from July 16 to August 15.
In Chinese astronomy, the stars of Cancer lie within the The Vermillion Bird of the South (南方朱雀, Nán Fāng Zhū Què). Sony VAIO VPCCW21FX/R Battery
In the 1998 Sega arcade game The Ocean Hunter, Karkinos is featured therein as one of seven boss characters.[5] Though Karkinos is depicted in the game as resembling a giant red king crab, its species is listed therein as Macrocheira kaempferi, or the Japanese spider crab. Sony VAIO VPCCW21FX/W Battery
In the final book in the Percy Jackson & the Olympians series, The Last Olympian, Percy Jackson fights a giant crab (Karkinos) on board the Titan cruise shipPrincess Andromeda. He kills it by stabbing its underbelly, its only uncovered, vulnerable point. Sony VAIO VPCCW26EC Battery,Sony VAIO VPCCW26FX/B Battery,Sony VAIO VPCCW28EC Battery,Sony VAIO VPCCW28FJ/P Battery
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