A star is type of astronomical object consisting of a luminous spheroid of plasma held together by its own gravity. The nearest star to Earth is the Sun. Many other stars are visible to the naked eye from Earth during the night, appearing as a multitude of fixed luminous points in the sky due to their immense distance from Earth; the most prominent stars were grouped into constellations and asterisms, the brightest of which gained proper names. Astronomers have assembled star catalogues that identify the known stars and provide standardized stellar designations. However, most of the estimated 300 sextillion stars in the Universe are invisible to the naked eye from Earth, including all stars outside our galaxy, the Milky Way. For at least a portion of its life, a star shines due to thermonuclear fusion of hydrogen into helium in its core, releasing energy that traverses the star's interior and radiates into outer space. All occurring elements heavier than helium are created by stellar nucleosynthesis during the star's lifetime, for some stars by supernova nucleosynthesis when it explodes.
Near the end of its life, a star can contain degenerate matter. Astronomers can determine the mass, age and many other properties of a star by observing its motion through space, its luminosity, spectrum respectively; the total mass of a star is the main factor. Other characteristics of a star, including diameter and temperature, change over its life, while the star's environment affects its rotation and movement. A plot of the temperature of many stars against their luminosities produces a plot known as a Hertzsprung–Russell diagram. Plotting a particular star on that diagram allows the age and evolutionary state of that star to be determined. A star's life begins with the gravitational collapse of a gaseous nebula of material composed of hydrogen, along with helium and trace amounts of heavier elements; when the stellar core is sufficiently dense, hydrogen becomes converted into helium through nuclear fusion, releasing energy in the process. The remainder of the star's interior carries energy away from the core through a combination of radiative and convective heat transfer processes.
The star's internal pressure prevents it from collapsing further under its own gravity. A star with mass greater than 0.4 times the Sun's will expand to become a red giant when the hydrogen fuel in its core is exhausted. In some cases, it will fuse heavier elements in shells around the core; as the star expands it throws a part of its mass, enriched with those heavier elements, into the interstellar environment, to be recycled as new stars. Meanwhile, the core becomes a stellar remnant: a white dwarf, a neutron star, or if it is sufficiently massive a black hole. Binary and multi-star systems consist of two or more stars that are gravitationally bound and move around each other in stable orbits; when two such stars have a close orbit, their gravitational interaction can have a significant impact on their evolution. Stars can form part of a much larger gravitationally bound structure, such as a star cluster or a galaxy. Stars have been important to civilizations throughout the world, they have used for celestial navigation and orientation.
Many ancient astronomers believed that stars were permanently affixed to a heavenly sphere and that they were immutable. By convention, astronomers grouped stars into constellations and used them to track the motions of the planets and the inferred position of the Sun; the motion of the Sun against the background stars was used to create calendars, which could be used to regulate agricultural practices. The Gregorian calendar used nearly everywhere in the world, is a solar calendar based on the angle of the Earth's rotational axis relative to its local star, the Sun; the oldest dated star chart was the result of ancient Egyptian astronomy in 1534 BC. The earliest known star catalogues were compiled by the ancient Babylonian astronomers of Mesopotamia in the late 2nd millennium BC, during the Kassite Period; the first star catalogue in Greek astronomy was created by Aristillus in 300 BC, with the help of Timocharis. The star catalog of Hipparchus included 1020 stars, was used to assemble Ptolemy's star catalogue.
Hipparchus is known for the discovery of the first recorded nova. Many of the constellations and star names in use today derive from Greek astronomy. In spite of the apparent immutability of the heavens, Chinese astronomers were aware that new stars could appear. In 185 AD, they were the first to observe and write about a supernova, now known as the SN 185; the brightest stellar event in recorded history was the SN 1006 supernova, observed in 1006 and written about by the Egyptian astronomer Ali ibn Ridwan and several Chinese astronomers. The SN 1054 supernova, which gave birth to the Crab Nebula, was observed by Chinese and Islamic astronomers. Medieval Islamic astronomers gave Arabic names to many stars that are still used today and they invented numerous astronomical instruments that could compute the positions of the stars, they built the first large observatory research institutes for the purpose of producing Zij star catalogues. Among these, the Book of Fixed Stars was written by the Persian astronomer Abd al-Rahman al-Sufi, who observed a number of stars, star clusters and galaxies.
According to A. Zahoor, in the 11th century, the Persian polymath scholar Abu Rayhan Biruni described the Milky
Well (Chinese constellation)
The Well mansion is one of the Twenty-eight mansions of the Chinese constellations. It is one of the southern mansions of the Vermilion Bird
Astronomy in China has a long history, beginning from the Shang Dynasty. Chinese star names categorized in the twenty-eight mansions have been found on oracle bones unearthed at Anyang, dating back to the middle Shang Dynasty, the mansion system's nucleus seems to have taken shape by the time of the ruler Wu Ding. Detailed records of astronomical observations began during the Warring States period and flourished from the Han period onward. Chinese astronomy was equatorial, centered as it was on close observation of circumpolar stars, was based on different principles from those prevailing in traditional Western astronomy, where heliacal risings and settings of zodiac constellations formed the basic ecliptic framework. Needham has described the ancient Chinese as the most persistent and accurate observers of celestial phenomena anywhere in the world before the Islamic astronomers; some elements of Indian astronomy reached China with the expansion of Buddhism after the Eastern Han Dynasty, but the most detailed incorporation of Indian astronomical thought occurred during the Tang Dynasty, when numerous Indian astronomers took up residence in the Chinese capital, Chinese scholars, such as the Tantric Buddhist monk and mathematician Yi Xing, mastered its system.
Islamic astronomers collaborated with their Chinese colleagues during the Yuan Dynasty, after a period of relative decline during the Ming Dynasty, astronomy was revitalized under the stimulus of Western cosmology and technology after the Jesuits established their missions. The telescope was introduced in the seventeenth century. In 1669, the Peking observatory was redesigned and refitted under the direction of Ferdinand Verbiest. Today, China continues to be active with many observatories and its own space program. One of the main functions was for the purpose of timekeeping; the Chinese used a lunisolar calendar, because the cycles of the Sun and the Moon are different, intercalation had to be done. The Chinese calendar was considered to be a symbol of a dynasty; as dynasties would rise and fall and astrologers of each period would prepare a new calendar to be made, with observations for that purpose. Astrological divination was an important part of astronomy. Astronomers took careful note of guest stars, which appeared among the fixed stars.
The supernova that created the Crab Nebula observed in 1054, now known as the SN 1054, is an example of a guest star observed by Chinese astronomers, recorded by the Arab astronomers, although it was not recorded by their European contemporaries. Ancient astronomical records of phenomena like comets and supernovae are sometimes used in modern astronomical studies. Indian astronomy reached China with the expansion of Buddhism during the Later Han. Further translation of Indian works on astronomy was completed in China by the Three Kingdoms era. However, the most detailed incorporation of Indian astronomy occurred only during the Tang Dynasty when a number of Chinese scholars—such as Yi Xing— were versed both in Indian and Chinese astronomy. A system of Indian astronomy was recorded in China as Jiuzhi-li, the author of, an Indian by the name of Qutan Xida—a translation of Devanagari Gotama Siddha—the director of the Tang dynasty's national astronomical observatory. During the 8th century, the astronomical table of sines by the Indian astronomer and mathematician, were translated into the Chinese astronomical and mathematical book of the Treatise on Astrology of the Kaiyuan Era, compiled in 718 CE during the Tang Dynasty.
The Kaiyuan Zhanjing was compiled by Gautama Siddha, an astronomer and astrologer born in Chang'an, whose family was from India. He was notable for his translation of the Navagraha calendar into Chinese. Gautama Siddha introduced Indian numerals with zero in 718 in China as a replacement of counting rods. In 3rd-century C. E, the Matanaga avadha was translated into Chinese.although the original is believed to date earlier. It gives the lengths of monthly shadows of a 12-inch gnomon, the standard parameter of Indian astronomy; the work mentions the 28 Indian nakshatras. In the beginning of the second century, Sardulakarnavadana was translated into Chinese several times, This work contains the usual Sanskrit names of the 28 nakshatras. Starting with krttika. From the 1st century onward Lalitavistara was translated into Chinese several times, it is in this work that the famous Buddhist centesimal-scale counting occurs during the dialogue between Prince Gautamaand and the mathematician Arjuna. The first series of counts ends with tallaksana, beyond which eight more ganana series are mentioned.
Atomic-scale counting is mentioned. The Mahaprajnaparamita Sastra was translated into Chinese by Kumarajiva in the early fifth century.16 The astronomical parameters mentioned in this translation are comparable to those given in the Vedanga Jyotisha. Indian system of numeration appeared in the Chinese work Ta PaoChi Ching, translated by Upasunya The Chinese translations of the following works are mentioned in the Sui Shu, or Official History of the Sui Dynasty: Po-lo-men Thien Wen Ching in 21 books. Po-lo-men Chieh-Chhieh Hsien-jen Thien Wen Shuo in 30 books. Po-lo-men Thien Ching in one book. Mo-teng-Chia Ching Huang-thu in onebook. Po-lo-men Suan Ching in three books. Po-lo-men Su
Canis Major is a constellation in the southern celestial hemisphere. In the second century, it was included in Ptolemy's 48 constellations, is counted among the 88 modern constellations, its name is Latin for "greater dog" in contrast to Canis Minor, the "lesser dog". The Milky Way passes through Canis Major and several open clusters lie within its borders, most notably M41. Canis Major contains Sirius, the brightest star in the night sky, known as the "dog star", it is bright because of its proximity to the Solar System. In contrast, the other bright stars of the constellation are stars of great distance and high luminosity. At magnitude 1.5, Epsilon Canis Majoris is the second-brightest star of the constellation and the brightest source of extreme ultraviolet radiation in the night sky. Next in brightness are the yellow-white supergiant Delta at 1.8, the blue-white giant Beta at 2.0, blue-white supergiants Eta at 2.4 and Omicron1 at 3.0, white spectroscopic binary Zeta at 3.0. The red hypergiant VY Canis Majoris is one of the largest stars known, while the neutron star RX J0720.4-3125 has a radius of a mere 5 km.
In ancient Mesopotamia, named KAK. SI. DI by the Babylonians, was seen as an arrow aiming towards Orion, while the southern stars of Canis Major and a part of Puppis were viewed as a bow, named BAN in the Three Stars Each tablets, dating to around 1100 BC. In the compendium of Babylonian astronomy and astrology titled MUL. APIN, the arrow, was linked with the warrior Ninurta, the bow with Ishtar, daughter of Enlil. Ninurta was linked to the deity Marduk, said to have slain the ocean goddess Tiamat with a great bow, worshipped as the principal deity in Babylon; the Ancient Greeks replaced the arrow depiction with that of a dog. In Greek Mythology, Canis Major represented a gift from Zeus to Europa, it was considered to represent one of Orion's hunting dogs, pursuing Lepus the Hare or helping Orion fight Taurus the Bull. The ancient Greeks refer only to one dog, but by Roman times, Canis Minor appears as Orion's second dog. Alternative names include Canis Sequens and Canis Alter. Canis Syrius was the name used in the 1521 Alfonsine tables.
The Roman myth refers to Canis Major as Custos Europae, the dog guarding Europa but failing to prevent her abduction by Jupiter in the form of a bull, as Janitor Lethaeus, "the watchdog". In medieval Arab astronomy, the constellation became al-Kalb al-Akbar, "the Greater Dog", transcribed as Alcheleb Alachbar by 17th century writer Edmund Chilmead. Islamic scholar Abū Rayḥān al-Bīrūnī referred to Orion as Kalb al-Jabbār, "the Dog of the Giant". Among the Merazig of Tunisia, shepherds note six constellations that mark the passage of the dry, hot season. One of them, called Merzem, includes the stars of Canis Major and Canis Minor and is the herald of two weeks of hot weather. In Chinese astronomy, the modern constellation of Canis Major is located in the Vermilion Bird, where the stars were classified in several separate asterisms of stars; the Military Market was a circular pattern of stars containing Nu3, Beta, Xi1 and Xi2, some stars from Lepus. The Wild Cockerel was at the centre of the Military Market, although it is uncertain which stars depicted what.
Schlegel reported that the stars Omicron and Pi Canis Majoris might have been them, while Beta or Nu2 have been proposed. Sirius was the Celestial Wolf, denoting invasion and plunder. Southeast of the Wolf was the asterism Húshǐ, the celestial Bow and Arrow, interpreted as containing Delta, Epsilon and Kappa Canis Majoris and Delta Velorum. Alternatively, the arrow was depicted by Omicron2 and Eta and aiming at Sirius, while the bow comprised Kappa, Sigma, Delta and 164 Canis Majoris, Pi and Omicron Puppis. Both the Māori people and the people of the Tuamotus recognized the figure of Canis Major as a distinct entity, though it was sometimes absorbed into other constellations. Te Huinga-o-Rehua called Te Putahi-nui-o-Rehua and Te Kahui-Takurua, was a Māori constellation that included both Canis Minor and Canis Major, along with some surrounding stars. Related was Taumata-o-Rehua called Pukawanui, the Mirror of Rehua, formed from an undefined group of stars in Canis Major, they called Sirius Rehua and Takarua, corresponding to two of the names for the constellation, though Rehua was a name applied to other stars in various Māori groups and other Polynesian cosmologies.
The Tuamotu people called Canis Major Muihanga-hetika-o-Takurua, "the abiding assemblage of Takarua". The Tharumba people of the Shoalhaven River saw three stars of Canis Major as Wunbula and his two wives Murrumbool and Moodtha, he spears them and all three are placed in the sky as the constellation Munowra. To the Boorong people of Victoria, Sigma Canis Majoris was Unurgunite, its flanking stars Delta and Epsilon were his two wives; the moon sought to lure the further wife away, but Unurgunite assaulted him and he has been wandering the sky since. Canis Major is a constellation in the Southern Hemisphere's summer sky, bordered by Mo
The radial velocity of an object with respect to a given point is the rate of change of the distance between the object and the point. That is, the radial velocity is the component of the object's velocity that points in the direction of the radius connecting the object and the point. In astronomy, the point is taken to be the observer on Earth, so the radial velocity denotes the speed with which the object moves away from or approaches the Earth. In astronomy, radial velocity is measured to the first order of approximation by Doppler spectroscopy; the quantity obtained by this method may be called the barycentric radial-velocity measure or spectroscopic radial velocity. However, due to relativistic and cosmological effects over the great distances that light travels to reach the observer from an astronomical object, this measure cannot be transformed to a geometric radial velocity without additional assumptions about the object and the space between it and the observer. By contrast, astrometric radial velocity is determined by astrometric observations.
Light from an object with a substantial relative radial velocity at emission will be subject to the Doppler effect, so the frequency of the light decreases for objects that were receding and increases for objects that were approaching. The radial velocity of a star or other luminous distant objects can be measured by taking a high-resolution spectrum and comparing the measured wavelengths of known spectral lines to wavelengths from laboratory measurements. A positive radial velocity indicates the distance between the objects was increasing. In many binary stars, the orbital motion causes radial velocity variations of several kilometers per second; as the spectra of these stars vary due to the Doppler effect, they are called spectroscopic binaries. Radial velocity can be used to estimate the ratio of the masses of the stars, some orbital elements, such as eccentricity and semimajor axis; the same method has been used to detect planets around stars, in the way that the movement's measurement determines the planet's orbital period, while the resulting radial-velocity amplitude allows the calculation of the lower bound on a planet's mass using the binary mass function.
Radial velocity methods alone may only reveal a lower bound, since a large planet orbiting at a high angle to the line of sight will perturb its star radially as much as a much smaller planet with an orbital plane on the line of sight. It has been suggested that planets with high eccentricities calculated by this method may in fact be two-planet systems of circular or near-circular resonant orbit; the radial velocity method to detect exoplanets is based on the detection of variations in the velocity of the central star, due to the changing direction of the gravitational pull from an exoplanet as it orbits the star. When the star moves towards us, its spectrum is blueshifted, while it is redshifted when it moves away from us. By looking at the spectrum of a star—and so, measuring its velocity—it can be determined if it moves periodically due to the influence of an exoplanet companion. From the instrumental perspective, velocities are measured relative to the telescope's motion. So an important first step of the data reduction is to remove the contributions of the Earth's elliptic motion around the sun at ± 30 km/s, a monthly rotation of ± 13 m/s of the Earth around the center of gravity of the Earth-Moon system, the daily rotation of the telescope with the Earth crust around the Earth axis, up to ±460 m/s at the equator and proportional to the cosine of the telescope's geographic latitude, small contributions from the Earth polar motion at the level of mm/s, contributions of 230 km/s from the motion around the Galactic center and associated proper motions.
In the case of spectroscopic measurements corrections of the order of ±20 cm/s with respect to aberration. Proper motion Peculiar velocity Relative velocity Space velocity The Radial Velocity Equation in the Search for Exoplanets
Hipparcos was a scientific satellite of the European Space Agency, launched in 1989 and operated until 1993. It was the first space experiment devoted to precision astrometry, the accurate measurement of the positions of celestial objects on the sky; this permitted the accurate determination of proper motions and parallaxes of stars, allowing a determination of their distance and tangential velocity. When combined with radial velocity measurements from spectroscopy, this pinpointed all six quantities needed to determine the motion of stars; the resulting Hipparcos Catalogue, a high-precision catalogue of more than 118,200 stars, was published in 1997. The lower-precision Tycho Catalogue of more than a million stars was published at the same time, while the enhanced Tycho-2 Catalogue of 2.5 million stars was published in 2000. Hipparcos' follow-up mission, was launched in 2013; the word "Hipparcos" is an acronym for HIgh Precision PARallax COllecting Satellite and a reference to the ancient Greek astronomer Hipparchus of Nicaea, noted for applications of trigonometry to astronomy and his discovery of the precession of the equinoxes.
By the second half of the 20th century, the accurate measurement of star positions from the ground was running into insurmountable barriers to improvements in accuracy for large-angle measurements and systematic terms. Problems were dominated by the effects of the Earth's atmosphere, but were compounded by complex optical terms and gravitational instrument flexures, the absence of all-sky visibility. A formal proposal to make these exacting observations from space was first put forward in 1967. Although proposed to the French space agency CNES, it was considered too complex and expensive for a single national programme, its acceptance within the European Space Agency's scientific programme, in 1980, was the result of a lengthy process of study and lobbying. The underlying scientific motivation was to determine the physical properties of the stars through the measurement of their distances and space motions, thus to place theoretical studies of stellar structure and evolution, studies of galactic structure and kinematics, on a more secure empirical basis.
Observationally, the objective was to provide the positions and annual proper motions for some 100,000 stars with an unprecedented accuracy of 0.002 arcseconds, a target in practice surpassed by a factor of two. The name of the space telescope, "Hipparcos" was an acronym for High Precision Parallax Collecting Satellite, it reflected the name of the ancient Greek astronomer Hipparchus, considered the founder of trigonometry and the discoverer of the precession of the equinoxes; the spacecraft carried a single all-reflective, eccentric Schmidt telescope, with an aperture of 29 cm. A special beam-combining mirror superimposed two fields of view, 58 degrees apart, into the common focal plane; this complex mirror consisted of two mirrors tilted in opposite directions, each occupying half of the rectangular entrance pupil, providing an unvignetted field of view of about 1°×1°. The telescope used a system of grids, at the focal surface, composed of 2688 alternate opaque and transparent bands, with a period of 1.208 arc-sec.
Behind this grid system, an image dissector tube with a sensitive field of view of about 38-arc-sec diameter converted the modulated light into a sequence of photon counts from which the phase of the entire pulse train from a star could be derived. The apparent angle between two stars in the combined fields of view, modulo the grid period, was obtained from the phase difference of the two star pulse trains. Targeting the observation of some 100,000 stars, with an astrometric accuracy of about 0.002 arc-sec, the final Hipparcos Catalogue comprised nearly 120,000 stars with a median accuracy of better than 0.001 arc-sec. An additional photomultiplier system viewed a beam splitter in the optical path and was used as a star mapper, its purpose was to monitor and determine the satellite attitude, in the process, to gather photometric and astrometric data of all stars down to about 11th magnitude. These measurements were made in two broad bands corresponding to B and V in the UBV photometric system.
The positions of these latter stars were to be determined to a precision of 0.03 arc-sec, a factor of 25 less than the main mission stars. Targeting the observation of around 400,000 stars, the resulting Tycho Catalogue comprised just over 1 million stars, with a subsequent analysis extending this to the Tycho-2 Catalogue of about 2.5 million stars. The attitude of the spacecraft about its center of gravity was controlled to scan the celestial sphere in a regular precessional motion maintaining a constant inclination between the spin axis and the direction to the Sun; the spacecraft spun around its Z-axis at the rate of 11.25 revolutions/day at an angle of 43° to the Sun. The Z-axis rotated about the sun-satellite line at 6.4 revolutions/year. The spacecraft consisted of two platforms and six vertical panels, all made of aluminum honeycomb; the solar array consisted of three deployable sections. Two S-band antennas were located on the top and bottom of the spacecraft, providing an omni-directional downlink data rate of 24 kbit/s.
An attitude and orbit-control subsystem ensured correct dynamic attitude control and determination during the operational lifetim
Traditional Chinese astronomy has a system of dividing the celestial sphere into asterisms or constellations, known as "officials". The Chinese asterisms are smaller than the constellations of Hellenistic tradition; the Song dynasty Suzhou planisphere shows a total of 283 asterisms, comprising a total of 1,565 individual stars. The asterisms are divided into four groups, the Twenty-Eight Mansions along the ecliptic, the Three Enclosures of the northern sky; the southern sky was added as a fifth group in the late Ming Dynasty based on European star charts, comprising an additional 23 asterisms. The Three Enclosures are centered on the North Celestial Pole and include those stars which could be seen year-round; the Twenty-Eight Mansions form an ecliptic coordinate system used for those stars visible but not during the whole year, based on the movement of the moon over a lunar month. The Chinese system developed independently from the Greco-Roman system since at least the 5th century BC, although there may have been earlier mutual influence, suggested by parallels to ancient Babylonian astronomy.
The system of twenty-eight lunar mansions is similar to the Indian Nakshatra system, it is not known if there was mutual influence in the history of the Chinese and Indian systems. The oldest extant Chinese star maps date to the Tang dynasty. Notable among them are the 8th-century Treatise on Astrology of the Kaiyuan Era and Dunhuang Star Chart, it contains collections of earlier Chinese astronomers as well as of Indian astronomy. Gan De was a Warring States era astronomer who according to the testimony of the Dunhuang Star Chart enumerated 810 stars in 138 asterisms; the Dunhuang Star Chart itself has 1,585 stars grouped into 257 asterisms. The number of asterisms, or of stars grouped into asterisms, never became fixed, but remained in the same order of magnitude; the 13th-century Suzhou star chart has 1,565 stars in 283 asterisms, the 14th-century Korean Cheonsang Yeolcha Bunyajido has 1,467 stars in 264 asterisms, the celestial globe made by Flemish Jesuit Ferdinand Verbiest for the Kangxi Emperor in 1673 has 1,876 stars in 282 asterisms.
The southern sky was unknown to the ancient Chinese and is not included in the traditional system. With European contact in the 16th century, Xu Guangqi, an astronomer of the late Ming Dynasty, introduced another 23 asterisms based on European star charts; the "Southern Sky" asterisms are now treated as part of the traditional Chinese system. The Chinese word for "star, heavenly body" is 星 xīng; the character 星 is phonosemantic, its ideographic portion is 晶, in origin depicting three twinkling stars. The modern Chinese term for "constellation" referring to the IAU system is 星座, while the term 星官 xīng guān remains reserved for the traditional system; the character 官 means "public official", but it is a variant glyph of 宮 gōng "temple, palace", in origin a pictogram of a large building. The generic term for "asterism" is 星群; the Three Enclosures are the Purple Forbidden enclosure, the Supreme Palace enclosure and the Heavenly Market enclosure. The Purple Forbidden Enclosure occupies the northernmost area of the night sky.
From the viewpoint of the ancient Chinese, the Purple Forbidden Enclosure lies in the middle of the sky and is circled by all the other stars. It covers the modern constellations Ursa Minor, Camelopardalis, Cassiopeia, Auriga, Boötes, parts of Ursa Major, Canes Venatici, Leo Minor, Hercules; the Supreme Palace Enclosure covers the modern constellations Virgo, Coma Berenices and Leo, parts of Canes Venatici, Ursa Major and Leo Minor. The Heavenly Market Enclosure covers the modern constellations Serpens, Ophiuchus and Corona Borealis, parts of Hercules; the Three Enclosures are each enclosed by two "wall" asterisms, designated 垣 yuán "fence. The names and determinative stars are: The sky around the south celestial pole was unknown to ancient Chinese. Therefore, it was not included in the Three Enclosures and Twenty-Eight Mansions system. However, by the end of the Ming Dynasty, Xu Guangqi introduced another 23 asterisms based on the knowledge of European star charts; these asterisms were since incorporated into the traditional Chinese star maps.
The asterisms are: Ancient Chinese astronomers designated names to the visible stars systematically more than one thousand years before Johann Bayer did it in a similar way. Every star is assigned to an asterism. A number is given to the individual stars in this asterism. Therefore, a star is designated as "Asterism name" + "Number"; the numbering of th