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79-563: Triangulum is a small constellation in the northern sky. Its name is Latin for " triangle ", derived from its three brightest stars, which form a long and narrow triangle. Known to the ancient Babylonians and Greeks, Triangulum was one of the 48 constellations listed by the 2nd century astronomer Ptolemy . The celestial cartographers Johann Bayer and John Flamsteed catalogued the constellation's stars, giving six of them Bayer designations . The white stars Beta and Gamma Trianguli , of apparent magnitudes 3.00 and 4.00, respectively, form

158-425: A celestial coordinate system lies in one of the modern constellations. Some astronomical naming systems include the constellation where a given celestial object is found to convey its approximate location in the sky. The Flamsteed designation of a star, for example, consists of a number and the genitive form of the constellation's name. Other star patterns or groups called asterisms are not constellations under

237-508: A burst of star formation in the last ten million years. The group is thought connected to another group of six galaxies known as the NGC 784 group, named for its principal galaxy, the barred spiral NGC 784 . Together with two isolated dwarf galaxies, these fourteen appear to be moving in a common direction and constitute a group possibly located on a dark matter filament . 3C 48 was the first quasar ever to be observed, although its true identity

316-421: A common centre of gravity every 31 days, and are surrounded by a ring of dust that extends from 50 to 400  AU away from the stars. The second-brightest star, the yellow-white subgiant star Alpha Trianguli (3.41) with a close dimmer companion, is also known as Caput Trianguli or Ras al Muthallath, and is at the apex of the triangle . It lies around 7 degrees north-northwest of Alpha Arietis . Making up

395-498: A great general in mythology. Later, the 17th-century German celestial cartographer Johann Bayer called the constellation Triplicitas and Orbis terrarum tripertitus, for the three regions Europe, Asia, and Africa. Triangulus Septentrionalis was a name used to distinguish it from Triangulum Australe , the Southern Triangle. Polish astronomer Johannes Hevelius excised three faint stars— ι , 10 and 12 Trianguli —to form

474-452: A list of 88 constellations with three-letter abbreviations for them. However, these constellations did not have clear borders between them. In 1928, the IAU formally accepted the 88 modern constellations, with contiguous boundaries along vertical and horizontal lines of right ascension and declination developed by Eugene Delporte that, together, cover the entire celestial sphere; this list

553-421: A long tradition of observing celestial phenomena. Nonspecific Chinese star names , later categorized in the twenty-eight mansions , have been found on oracle bones from Anyang , dating back to the middle Shang dynasty . These constellations are some of the most important observations of Chinese sky, attested from the 5th century BC. Parallels to the earliest Babylonian (Sumerian) star catalogues suggest that

632-470: A natural but quite faint asterism in which the star 20 Psc is the head of the turtle. While Admiral Smyth mentioned the proposal, it was largely neglected by other astronomers, and it is now obsolete . The Fishes are in the German lore of Antenteh, who owned just a tub and a crude cabin when he met two magical fish. They offered him a wish, which he refused. However, his wife begged him to return to

711-517: A visual magnitude of 8.42. A huge starspot larger than the diameter of the Sun was detected on its surface in 1999 by astronomers using Doppler imaging . Two star systems appear to have planets . HD 9446 is a Sun-like star around 171 light-years distant that has two planets of masses 0.7 and 1.8 times that of Jupiter , with orbital periods of 30 and 193 days respectively. HD 13189 is an orange giant of spectral type K2II about 2–7 times as massive as

790-459: Is a spectroscopic binary system composed of two yellow main sequence stars of similar dimensions to the Sun that lies 35 light-years from Earth. The two stars orbit each other every ten days and are a mere 0.1 AU apart. This system is the closest in the constellation to the Earth. Only of magnitude 5.25, 7 Trianguli is much further away at around 280 light-years distant from Earth. Iota Trianguli

869-455: Is a double star whose components can be separated by medium-sized telescopes into a strong yellow and a contrasting pale blue star. Both of these are themselves close binaries. X Trianguli is an eclipsing binary system that ranges between magnitudes 8.5 and 11.2 over a period of 0.97 days. RW Trianguli is a cataclysmic variable star system composed of a white dwarf primary and an orange main sequence star of spectral type K7 V. The former

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948-419: Is a massive galaxy cluster that lenses the galaxy behind it, creating arc-shaped images of the background galaxy. The cluster is primarily made up of yellow elliptical and spiral galaxies, at a distance of 3.6 billion light-years from Earth (redshift 0.4), half as far away as the background galaxy, which is at a distance of 5.7 billion light-years (redshift 1.67). Pisces originates from some composition of

1027-525: Is also a different origin tale that Hyginus preserved in another work. According to this, an egg rolled into the Euphrates, and some fishes nudged this to shore, after which the doves sat on the egg until Aphrodite (thereafter called the Syrian Goddess ) hatched out of it. The fishes were then rewarded by being placed in the skies as a constellation ( Fabulae 197). This story is also recorded by

1106-556: Is bright enough to be seen by the naked eye under dark skies. Being a diffuse object, it is challenging to see under light-polluted skies, even with a small telescope or binoculars, and low power is required to view it. It is a spiral galaxy with a diameter of 46,000 light-years and is thus smaller than both the Andromeda Galaxy and the Milky Way . A distance of less than 300 kiloparsecs between it and Andromeda supports

1185-439: Is drawing off matter from the latter, forming a prominent accretion disc . The system is around 1075 light-years distant. R Trianguli is a long period (Mira) variable that ranges from magnitude 6.2 to 11.7 over a period of 267 days. It is a red giant of spectral type M3.5-8e, lying around 960 light-years away. HD 12545 , also known as XX Trianguli, is an orange giant of spectral type K0III around 520 light-years distant with

1264-471: Is located within the boundaries of Pisces. The March equinox is currently located in Pisces, due south of Psc, and, due to precession , slowly drifting due west, just below the western fish towards Aquarius . Although Pisces is a large constellation, there are only two stars brighter than magnitude 4 in Pisces. It is also the second dimmest of the zodiac constellations. Due to the dimness of these stars,

1343-645: Is the Suzhou Astronomical Chart , which was prepared with carvings of stars on the planisphere of the Chinese sky on a stone plate; it is done accurately based on observations, and it shows the supernova of the year of 1054 in Taurus. Influenced by European astronomy during the late Ming dynasty , charts depicted more stars but retained the traditional constellations. Newly observed stars were incorporated as supplementary to old constellations in

1422-450: Is the white giant star Beta Trianguli of apparent magnitude 3.00, lying 127 light-years distant from Earth. It is actually a spectroscopic binary system; the primary is a white star of spectral type A5IV with 3.5 times the mass of the Sun that is beginning to expand and evolve off the main sequence. The secondary is poorly known, but calculated to be a yellow-white F-type main-sequence star around 1.4 solar masses. The two orbit around

1501-745: The Babylonian constellations Šinunutu 4 "the great swallow" in current western Pisces, and Anunitum the "Lady of the Heaven", at the place of the northern fish. In the first-millennium BC texts known as the Astronomical Diaries , part of the constellation was also called DU.NU.NU ( Rikis-nu.mi , "the fish cord or ribbon"). Pisces is associated with the Greek legend that Aphrodite and her son Eros either shape-shifted into forms of fishes to escape, or were rescued by two fishes. In

1580-620: The Inca civilization identified various dark areas or dark nebulae in the Milky Way as animals and associated their appearance with the seasonal rains. Australian Aboriginal astronomy also describes dark cloud constellations, the most famous being the "emu in the sky" whose head is formed by the Coalsack , a dark nebula, instead of the stars. Footnotes Citations Pisces (constellation) The right ascension / declination 00

1659-564: The KJV , but ‘Ayish "the bier" actually corresponding to Ursa Major. The term Mazzaroth מַזָּרוֹת , translated as a garland of crowns , is a hapax legomenon in Job 38:32, and it might refer to the zodiacal constellations. There is only limited information on ancient Greek constellations, with some fragmentary evidence being found in the Works and Days of the Greek poet Hesiod , who mentioned

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1738-576: The Third Vatican Mythographer . In 1690, the astronomer Johannes Hevelius in his Firmamentum Sobiescianum regarded the constellation Pisces as being composed of four subdivisions: " Piscis Austrinus " more often refers to a separate constellation in its own right. In 1754, the botanist and author John Hill proposed to sever a southern zone of Pisces as Testudo (the Turtle). 24 – 27 – YY(30) – 33 – 29 Psc., It would host

1817-675: The Zodiac of Dendera ; it remains unclear when this occurred, but most were placed during the Roman period between 2nd to 4th centuries AD. The oldest known depiction of the zodiac showing all the now familiar constellations, along with some original Egyptian constellations, decans , and planets . Ptolemy's Almagest remained the standard definition of constellations in the medieval period both in Europe and in Islamic astronomy . Ancient China had

1896-620: The declination coordinates are between 25.60° and 37.35°. Covering 132 square degrees and 0.320% of the night sky, Triangulum ranks 78th of the 88 constellations in size. Bayer catalogued five stars in the constellation, giving them the Bayer designations Alpha to Epsilon. John Flamsteed added Eta, Iota and four Roman letters; of these, only Iota is still used as the others were dropped in subsequent catalogues and star charts. Flamsteed gave 16 stars Flamsteed designations , of which numbers 1 and 16 are not used—1's coordinates were in error as there

1975-592: The horizon when viewed from a particular latitude on Earth is termed circumpolar . From the North Pole or South Pole , all constellations south or north of the celestial equator are circumpolar . Depending on the definition, equatorial constellations may include those that lie between declinations 45° north and 45° south, or those that pass through the declination range of the ecliptic (or zodiac ) ranging between 23.5° north and 23.5° south . Stars in constellations can appear near each other in

2054-525: The zodiac (straddling the ecliptic , which the Sun , Moon , and planets all traverse). The origins of the zodiac remain historically uncertain; its astrological divisions became prominent c. 400 BC in Babylonian or Chaldean astronomy. Constellations appear in Western culture via Greece and are mentioned in the works of Hesiod , Eudoxus and Aratus . The traditional 48 constellations, consisting of

2133-525: The "Way of Enlil "—that is, the northernmost quarter of the Sun's path, which corresponds to the 45 days on either side of summer solstice . Its first appearance in the pre-dawn sky ( heliacal rising ) in February marked the time to begin spring ploughing in Mesopotamia . The Ancient Greeks called Triangulum Deltoton (Δελτωτόν), as the constellation resembled an upper-case Greek letter delta (Δ). It

2212-458: The "heavenly bodies". Greek astronomy essentially adopted the older Babylonian system in the Hellenistic era , first introduced to Greece by Eudoxus of Cnidus in the 4th century BC. The original work of Eudoxus is lost, but it survives as a versification by Aratus , dating to the 3rd century BC. The most complete existing works dealing with the mythical origins of the constellations are by

2291-403: The 10 arcminute long magnitude 12 NGC 925 spiral galaxy and the 5 arcminute long magnitude 11.6 NGC 672 barred spiral galaxy. The latter is close by and appears to be interacting with IC 1727 . The two are 88,000 light-years apart and lie around 18 million light-years away. These two plus another four nearby dwarf irregular galaxies constitute the NGC 672 group, and all six appear to have had

2370-607: The 14th century. The Ancient Greek word for constellation is ἄστρον ( astron ). These terms historically referred to any recognisable pattern of stars whose appearance was associated with mythological characters or creatures, earthbound animals, or objects. Over time, among European astronomers, the constellations became clearly defined and widely recognised. In the 20th century, the International Astronomical Union (IAU) recognized 88 constellations . A constellation or star that never sets below

2449-529: The 17,000-year-old cave paintings in Lascaux , southern France, depict star constellations such as Taurus, Orion's Belt, and the Pleiades. However, this view is not generally accepted among scientists. Inscribed stones and clay writing tablets from Mesopotamia (in modern Iraq) dating to 3000 BC provide the earliest generally accepted evidence for humankind's identification of constellations. It seems that

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2528-556: The 88 IAU-recognized constellations in this region first appeared on celestial globes developed in the late 16th century by Petrus Plancius , based mainly on observations of the Dutch navigators Pieter Dirkszoon Keyser and Frederick de Houtman . These became widely known through Johann Bayer 's star atlas Uranometria of 1603. Fourteen more were created in 1763 by the French astronomer Nicolas Louis de Lacaille , who also split

2607-497: The Greek version according to Hyginus , Aphrodite and Eros while visiting Syria fled from the monster Typhon by leaping into the Euphrates River and transforming into fishes ( Poeticon astronomicon 2.30, citing Diognetus Erythraeus). The Roman variant of the story has Venus and Cupid (counterparts for Aphrodite and Eros) carried away from this danger on the backs of two fishes ( Ovid Fasti 2.457ff). There

2686-742: The Hellenistic writer termed pseudo-Eratosthenes and an early Roman writer styled pseudo- Hyginus . The basis of Western astronomy as taught during Late Antiquity and until the Early Modern period is the Almagest by Ptolemy , written in the 2nd century. In the Ptolemaic Kingdom , native Egyptian tradition of anthropomorphic figures represented the planets, stars, and various constellations. Some of these were combined with Greek and Babylonian astronomical systems culminating in

2765-504: The IAU as well as those by cultures throughout history are imagined figures and shapes derived from the patterns of stars in the observable sky. Many officially recognized constellations are based on the imaginations of ancient, Near Eastern and Mediterranean mythologies. Some of these stories seem to relate to the appearance of the constellations, e.g. the assassination of Orion by Scorpius, their constellations appearing at opposite times of year. Constellation positions change throughout

2844-572: The Navigator in c. 500 BC. The history of southern constellations is not straightforward. Different groupings and different names were proposed by various observers, some reflecting national traditions or designed to promote various sponsors. Southern constellations were important from the 14th to 16th centuries, when sailors used the stars for celestial navigation . Italian explorers who recorded new southern constellations include Andrea Corsali , Antonio Pigafetta , and Amerigo Vespucci . Many of

2923-498: The Sun with a planetary or brown dwarf companion between 8 and 20 times as massive as Jupiter, which takes 472 days to complete an orbit. It is one of the largest stars discovered to have a planetary companion. The Triangulum Galaxy , also known as Messier 33, was discovered by Giovanni Battista Hodierna in the 17th century. A distant member of the Local Group , it is about 2.3 million light-years away, and at magnitude 5.8 it

3002-647: The ancient Chinese system did not arise independently. Three schools of classical Chinese astronomy in the Han period are attributed to astronomers of the earlier Warring States period . The constellations of the three schools were conflated into a single system by Chen Zhuo , an astronomer of the 3rd century ( Three Kingdoms period ). Chen Zhuo's work has been lost, but information on his system of constellations survives in Tang period records, notably by Qutan Xida . The oldest extant Chinese star chart dates to that period and

3081-409: The ancient constellation Argo Navis into three; these new figures appeared in his star catalogue, published in 1756. Several modern proposals have not survived. The French astronomers Pierre Lemonnier and Joseph Lalande , for example, proposed constellations that were once popular but have since been dropped. The northern constellation Quadrans Muralis survived into the 19th century (when its name

3160-560: The base of the triangle and the yellow-white Alpha Trianguli , of magnitude 3.41, the apex. Iota Trianguli is a notable double star system, and there are three star systems with known planets located in Triangulum. The constellation contains several galaxies, the brightest and nearest of which is the Triangulum Galaxy or Messier 33—a member of the Local Group . The first quasar ever observed, 3C 48 , also lies within

3239-458: The boundaries of Triangulum. In the Babylonian star catalogues , Triangulum, together with Gamma Andromedae , formed the constellation known as APIN ( 𒀯𒀳 ) "The Plough". It is notable as the first constellation presented on (and giving its name to) a pair of tablets containing canonical star lists that were compiled around 1000 BC, the MUL.APIN . The Plough was the first constellation of

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3318-733: The bulk of the Mesopotamian constellations were created within a relatively short interval from around 1300 to 1000 BC. Mesopotamian constellations appeared later in many of the classical Greek constellations. The oldest Babylonian catalogues of stars and constellations date back to the beginning of the Middle Bronze Age , most notably the Three Stars Each texts and the MUL.APIN , an expanded and revised version based on more accurate observation from around 1000 BC. However,

3397-655: The celestial equator), and southern constellations Puppis , Vela , Carina , Crux , Centaurus , Triangulum Australe , and Ara . Polaris , being the North Star, is the approximate center of the northern celestial hemisphere. It is part of Ursa Minor , constituting the end of the Little Dipper's handle. From latitudes of around 35° north, in January, Ursa Major (containing the Big Dipper ) appears to

3476-430: The constellation is essentially invisible in or near any major city due to light pollution . M74 is a loosely wound (type Sc) spiral galaxy in Pisces, found at a distance of 30 million light years ( redshift 0.0022). It has many clusters of young stars and the associated nebulae , showing extensive regions of star formation . It was discovered by Pierre Méchain , a French astronomer, in 1780. A type II-P supernova

3555-661: The daytime and lower at night, while in winter the reverse is true, for both hemispheres. Due to the Solar System 's 60° tilt, the galactic plane of the Milky Way is inclined 60° from the ecliptic, between Taurus and Gemini (north) and Scorpius and Sagittarius (south and near which the Galactic Center can be found). The galaxy appears to pass through Aquila (near the celestial equator) and northern constellations Cygnus , Cassiopeia , Perseus , Auriga , and Orion (near Betelgeuse ), as well as Monoceros (near

3634-524: The development of today's accepted modern constellations. The southern sky, below about −65° declination , was only partially catalogued by ancient Babylonians, Egyptians, Greeks, Chinese, and Persian astronomers of the north. The knowledge that northern and southern star patterns differed goes back to Classical writers, who describe, for example, the African circumnavigation expedition commissioned by Egyptian Pharaoh Necho II in c. 600 BC and those of Hanno

3713-432: The early 20th century before today's constellations were internationally recognized. The recognition of constellations has changed significantly over time. Many changed in size or shape. Some became popular, only to drop into obscurity. Some were limited to a single culture or nation. Naming constellations also helped astronomers and navigators identify stars more easily. Twelve (or thirteen) ancient constellations belong to

3792-399: The early constellations were never universally adopted. Stars were often grouped into constellations differently by different observers, and the arbitrary constellation boundaries often led to confusion as to which constellation a celestial object belonged. Before astronomers delineated precise boundaries (starting in the 19th century), constellations generally appeared as ill-defined regions of

3871-425: The ecliptic), approximating a great circle . Zodiacal constellations of the northern sky are Pisces , Aries , Taurus , Gemini , Cancer , and Leo . In the southern sky are Virgo , Libra , Scorpius , Sagittarius , Capricornus , and Aquarius . The zodiac appears directly overhead from latitudes of 23.5° north to 23.5° south, depending on the time of year. In summer, the ecliptic appears higher up in

3950-605: The fish and ask for a beautifully furnished home. This wish was granted, but her desires were not satisfied. She then asked to be a queen and have a palace, but when she asked to become a goddess, the fish became angry and took the palace and home, leaving the couple with the tub and cabin once again. The tub is sometimes recognized as the Great Square of Pegasus . The stars of Pisces were incorporated into several constellations in Chinese astronomy . Wai-ping ("Outer Enclosure")

4029-507: The form of star charts , whose oldest representation appears on the statue known as the Farnese Atlas , based perhaps on the star catalogue of the Greek astronomer Hipparchus . Southern constellations are more modern inventions, sometimes as substitutes for ancient constellations (e.g. Argo Navis ). Some southern constellations had long names that were shortened to more usable forms; e.g. Musca Australis became simply Musca. Some of

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4108-621: The formal definition, but are also used by observers to navigate the night sky. Asterisms may be several stars within a constellation, or they may share stars with more than one constellation. Examples of asterisms include the teapot within the constellation Sagittarius , or the big dipper in the constellation of Ursa Major . The word constellation comes from the Late Latin term cōnstellātiō , which can be translated as "set of stars"; it came into use in Middle English during

4187-479: The hypothesis that it is a satellite of the larger galaxy. It is believed to have been interacting with it from their velocities. Within the constellation, it lies near the border of Pisces, 3.5 degrees west-northwest of Alpha Trianguli and 7 degrees southwest of Beta Andromedae . Within the galaxy, NGC 604 is an H II region where star formation takes place. In addition to M33, there are several NGC galaxies of visual magnitudes 12 to 14. The largest of these include

4266-480: The mid-18th century when European explorers began traveling to the Southern Hemisphere . Due to Roman and European transmission, each constellation has a Latin name. In 1922, the International Astronomical Union (IAU) formally accepted the modern list of 88 constellations , and in 1928 adopted official constellation boundaries that together cover the entire celestial sphere. Any given point in

4345-403: The new constellation of Triangulum Minus in his 1690 Firmamentum Sobiescianum , renaming the original as Triangulum Majus. The smaller constellation was not recognised by the International Astronomical Union (IAU) when the constellations were established in the 1920s . A small constellation, Triangulum is bordered by Andromeda to the north and west, Pisces to the west and south, Aries to

4424-449: The northeast, while Cassiopeia is the northwest. To the west are Pisces (above the horizon) and Aries. To the southwest Cetus is near the horizon. Up high and to the south are Orion and Taurus. To the southeast above the horizon is Canis Major . Appearing above and to the east of Orion is Gemini : also in the east (and progressively closer to the horizon) are Cancer and Leo. In addition to Taurus, Perseus and Auriga appear overhead. From

4503-602: The numerous Sumerian names in these catalogues suggest that they built on older, but otherwise unattested, Sumerian traditions of the Early Bronze Age . The classical Zodiac is a revision of Neo-Babylonian constellations from the 6th century BC. The Greeks adopted the Babylonian constellations in the 4th century BC. Twenty Ptolemaic constellations are from the Ancient Near East. Another ten have

4582-538: The parts of the southern sky unknown to Ptolemy) by Petrus Plancius (1592, 1597/98 and 1613), Johannes Hevelius (1690) and Nicolas Louis de Lacaille (1763), who introduced fourteen new constellations. Lacaille studied the stars of the southern hemisphere from 1751 until 1752 from the Cape of Good Hope , when he was said to have observed more than 10,000 stars using a refracting telescope with an aperture of 0.5 inches (13 mm). In 1922, Henry Norris Russell produced

4661-455: The pole star include Chamaeleon , Apus and Triangulum Australe (near Centaurus), Pavo , Hydrus , and Mensa . Sigma Octantis is the closest star approximating a southern pole star, but is faint in the night sky. Thus, the pole can be triangulated using the constellation Crux as well as the stars Alpha and Beta Centauri (about 30° counterclockwise from Crux) of the constellation Centaurus (arching over Crux). It has been suggested that

4740-695: The same latitude, in July, Cassiopeia (low in the sky) and Cepheus appear to the northeast. Ursa Major is now in the northwest. Boötes is high up in the west. Virgo is to the west, with Libra southwest and Scorpius south. Sagittarius and Capricorn are southeast. Cygnus (containing the Northern Cross ) is to the east. Hercules is high in the sky along with Corona Borealis . January constellations include Pictor and Reticulum (near Hydrus and Mensa, respectively). In July, Ara (adjacent to Triangulum Australe) and Scorpius can be seen. Constellations near

4819-836: The same stars but different names. Biblical scholar E. W. Bullinger interpreted some of the creatures mentioned in the books of Ezekiel and Revelation as the middle signs of the four-quarters of the Zodiac, with the Lion as Leo , the Bull as Taurus , the Man representing Aquarius , and the Eagle standing in for Scorpio . The biblical Book of Job also makes reference to a number of constellations, including עיש ‘Ayish "bier", כסיל chesil "fool" and כימה chimah "heap" (Job 9:9, 38:31–32), rendered as "Arcturus, Orion and Pleiades" by

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4898-518: The sky, but they usually lie at a variety of distances away from the Earth. Since each star has its own independent motion, all constellations will change slowly over time. After tens to hundreds of thousands of years, familiar outlines will become unrecognizable. Astronomers can predict the past or future constellation outlines by measuring common proper motions of individual stars by accurate astrometry and their radial velocities by astronomical spectroscopy . The 88 constellations recognized by

4977-564: The sky. Today they now follow officially accepted designated lines of right ascension and declination based on those defined by Benjamin Gould in epoch 1875.0 in his star catalogue Uranometria Argentina . The 1603 star atlas " Uranometria " of Johann Bayer assigned stars to individual constellations and formalized the division by assigning a series of Greek and Latin letters to the stars within each constellation. These are known today as Bayer designations . Subsequent star atlases led to

5056-493: The south, and Perseus to the east. The centre of the constellation lies halfway between Gamma Andromedae and Alpha Arietis . The three-letter abbreviation for the constellation, as adopted by the IAU in 1922, is "Tri". The official constellation boundaries, as set by Belgian astronomer Eugène Delporte in 1930, are defined as a polygon of 14 segments. In the equatorial coordinate system , the right ascension coordinates of these borders lie between 01 31.3 and 02 50.4 , while

5135-536: The southern hemisphere of the sky based on the knowledge of Western star charts; with this improvement, the Chinese Sky was integrated with the World astronomy. Historically, the origins of the constellations of the northern and southern skies are distinctly different. Most northern constellations date to antiquity, with names based mostly on Classical Greek legends. Evidence of these constellations has survived in

5214-595: The southern sky, which did not depict the traditional stars recorded by ancient Chinese astronomers. Further improvements were made during the later part of the Ming dynasty by Xu Guangqi and Johann Adam Schall von Bell , the German Jesuit and was recorded in Chongzhen Lishu (Calendrical Treatise of Chongzhen period , 1628). Traditional Chinese star maps incorporated 23 new constellations with 125 stars of

5293-462: The triangle is Gamma Trianguli , a white main sequence star of spectral type A1Vnn of apparent magnitude 4.00 about 112 light-years from Earth. It is around double the size of and around 33 times as luminous as the sun and rotates rapidly. Like Beta, it is surrounded by a dusty debris disk, which has a radius 80 times the distance of the Earth from the Sun. Lying near Gamma and forming an optical triple system with it are Delta and 7 Trianguli . Delta

5372-409: The year due to night on Earth occurring at gradually different portions of its orbit around the Sun. As Earth rotates toward the east, the celestial sphere appears to rotate west, with stars circling counterclockwise around the northern pole star and clockwise around the southern pole star. Because of Earth's 23.5° axial tilt , the zodiac is distributed equally across hemispheres (along

5451-451: The years and centuries to come. The constellations have no official symbols, though those of the ecliptic may take the signs of the zodiac. Symbols for the other modern constellations, as well as older ones that still occur in modern nomenclature, have occasionally been published. The Great Rift, a series of dark patches in the Milky Way, is most visible in the southern sky. Some cultures have discerned shapes in these patches. Members of

5530-525: The zodiac and 36 more (now 38, following the division of Argo Navis into three constellations) are listed by Ptolemy , a Greco-Roman astronomer from Alexandria , Egypt, in his Almagest . The formation of constellations was the subject of extensive mythology , most notably in the Metamorphoses of the Latin poet Ovid . Constellations in the far southern sky were added from the 15th century until

5609-399: Was Romanized as Trigonum. Other names referring to its shape include Tricuspis and Triquetrum. Alpha and Beta Trianguli were called Al Mīzān , which is Arabic for "The Scale Beam". In Chinese astronomy, Gamma Andromedae and neighbouring stars including Beta, Gamma and Delta Trianguli were called Teen Ta Tseang Keun (天大将军, "Heaven's great general"), representing honour in astrology and

5688-467: Was attached to the Quadrantid meteor shower), but is now divided between Boötes and Draco . A list of 88 constellations was produced for the IAU in 1922. It is roughly based on the traditional Greek constellations listed by Ptolemy in his Almagest in the 2nd century and Aratus ' work Phenomena , with early modern modifications and additions (most importantly introducing constellations covering

5767-558: Was discovered in the outer regions of M74 by Robert Evans in June 2003; the star that underwent the supernova was later identified as a red supergiant with a mass of 8 solar masses . It is the brightest member of the M74 Group . NGC 488 is an isolated face-on prototypical spiral galaxy. Two supernovae have been observed in the galaxy. NGC 520 is a pair of colliding galaxies located 105 million light-years away. CL 0024+1654

5846-498: Was finally published in 1930. Where possible, these modern constellations usually share the names of their Graeco-Roman predecessors, such as Orion, Leo, or Scorpius. The aim of this system is area-mapping, i.e. the division of the celestial sphere into contiguous fields. Out of the 88 modern constellations, 36 lie predominantly in the northern sky, and the other 52 predominantly in the southern. The boundaries developed by Delporte used data that originated back to epoch B1875.0 , which

5925-432: Was no star present at the location that corresponds to any star in his Catalogus Britannicus ; Baily presumed that the coordinates were mistranscribed 32 in error by Flamsteed and in fact referred to 7.4 magnitude HD 10407. Baily also noted that 16 Trianguli was closer to Aries and included it in the latter constellation. Three stars make up the long narrow triangle that gives the constellation its name. The brightest member

6004-685: Was not uncovered until after that of 3C 273 in 1963. It has an apparent magnitude of 16.2 and is located about 5 degrees northwest of Alpha Trianguli. Constellation Four views of the constellation Orion : A constellation is an area on the celestial sphere in which a group of visible stars forms a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The first constellations were likely defined in prehistory . People used them to relate stories of their beliefs, experiences, creation , and mythology . Different cultures and countries invented their own constellations, some of which lasted into

6083-688: Was preserved as part of the Dunhuang Manuscripts . Native Chinese astronomy flourished during the Song dynasty , and during the Yuan dynasty became increasingly influenced by medieval Islamic astronomy (see Treatise on Astrology of the Kaiyuan Era ). As maps were prepared during this period on more scientific lines, they were considered as more reliable. A well-known map from the Song period

6162-606: Was transliterated by Roman writers, then later Latinised as Deltotum. Eratosthenes linked it with the Nile Delta , while the Roman writer Hyginus associated it with the triangular island of Sicily , formerly known as Trinacria due to its shape. It was also called Sicilia , because the Romans believed Ceres , patron goddess of Sicily, begged Jupiter to place the island in the heavens. Greek astronomers such as Hipparchos and Ptolemy called it Trigonon (Τρίγωνον), and later, it

6241-406: Was when Benjamin A. Gould first made his proposal to designate boundaries for the celestial sphere, a suggestion on which Delporte based his work. The consequence of this early date is that because of the precession of the equinoxes , the borders on a modern star map, such as epoch J2000 , are already somewhat skewed and no longer perfectly vertical or horizontal. This effect will increase over

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