Coma Berenices is an ancient asterism in the northern sky, which has been defined as one of the 88 modern constellations. It is in the direction of the fourth

galactic quadrant A galactic quadrant, or quadrant of the Galaxy, is one of four circular sectors in the division of the Milky Way Galaxy. Quadrants in the galactic coordinate system In actual astronomical practice, the delineation of the galactic quadrants ...

, between Leo and Boötes, and it is visible in both hemispheres. Its name means "Berenice's Hair" in

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

and refers to Queen Berenice II of Egypt, who sacrificed her long hair as a

votive offering A votive offering or votive deposit is one or more objects displayed or deposited, without the intention of recovery or use, in a sacred place for religious purposes. Such items are a feature of modern and ancient societies and are generally ...

. It was introduced to Western astronomy during the third century BC by Conon of Samos and was further corroborated as a constellation by

Gerardus Mercator Gerardus Mercator (; 5 March 1512 – 2 December 1594) was a 16th-century geographer, cosmographer and Cartography, cartographer from the County of Flanders. He is most renowned for creating the Mercator 1569 world map, 1569 world map based on ...

and

Tycho Brahe Tycho Brahe ( ; born Tyge Ottesen Brahe; generally called Tycho (14 December 154624 October 1601) was a Danish astronomer, known for his comprehensive astronomical observations, generally considered to be the most accurate of his time. He was ...

. It is the only modern constellation named for a historic person. The constellation's major stars are Alpha, Beta, and Gamma Comae Berenices. They form a half square, along the diagonal of which run Berenice's imaginary tresses, formed by the

Coma Star Cluster The Coma Star Cluster (also known as Melotte 111 or Collinder 256) is a small but nearby open cluster located in the constellation Coma Berenices. The cluster contains about 40 brighter stars (between magnitudes 5 and 10) with a common proper mo ...

. The constellation's brightest star is Beta Comae Berenices, a 4.2-

magnitude Magnitude may refer to: Mathematics *Euclidean vector, a quantity defined by both its magnitude and its direction *Magnitude (mathematics), the relative size of an object *Norm (mathematics), a term for the size or length of a vector *Order of ...

main sequence star similar to the Sun. Coma Berenices contains the North Galactic Pole and one of the richest-known

galaxy cluster A galaxy cluster, or a cluster of galaxies, is a structure that consists of anywhere from hundreds to thousands of galaxies that are bound together by gravity, with typical masses ranging from 1014 to 1015 solar masses. They are the second-lar ...

s, the Coma Cluster, part of the

Coma Supercluster The Coma Supercluster (SCl 117) is a nearby supercluster of galaxies comprising the Coma Cluster (Abell 1656) and the Leo Cluster (Abell 1367). Located 300 million light-years from Earth, it is in the center of the Great Wall and a part of the Co ...

. Galaxy Malin 1, in the constellation, is the first-known giant low-surface-brightness galaxy. Supernova SN 1940B was the first scientifically observed (underway) type II supernova.

FK Comae Berenices FK Comae Berenices is a variable star that varies in apparent magnitude between 8.14 and 8.33 over a period of 2.4 days. It is the prototype for the FK Comae Berenices (FK Com) class of variable stars. The variability of FK Com stars may ...

is the prototype of an eponymous class of variable stars. The constellation is the radiant of one meteor shower, Coma Berenicids, which has one of the fastest meteor speeds, up to .

History

Coma Berenices has been recognized as an asterism since the

Hellenistic period In Classical antiquity, the Hellenistic period covers the time in Mediterranean history after Classical Greece, between the death of Alexander the Great in 323 BC and the emergence of the Roman Empire, as signified by the Battle of Actium in ...

(or much earlier, according to some authors), and is the only modern constellation named for an historic figure. It was introduced to Western astronomy during the third century BC by Conon of Samos, the court astronomer of Egyptian ruler

Ptolemy III Euergetes , predecessor = Ptolemy II , successor = Ptolemy IV , nebty = ''ḳn nḏtj-nṯrw jnb-mnḫ-n-tꜢmrj'Qen nedjtinetjeru inebmenekhentamery''The brave one who has protected the gods, a potent wall for The Beloved Land , nebty_hiero ...

, to honour Ptolemy's consort, Berenice II. Berenice vowed to sacrifice her long hair as a

if Ptolemy returned safely from battle during the

Third Syrian War The Syrian Wars were a series of six wars between the Seleucid Empire and the Ptolemaic Kingdom of Egypt, successor states to Alexander the Great's empire, during the 3rd and 2nd centuries BC over the region then called Coele-Syria, one of th ...

. Modern scholars are uncertain if Berenice made the sacrifice before or after Ptolemy's return; it was suggested that it happened after Ptolemy's return (around March–June or May 245 BC), when Conon presented the asterism jointly with scholar and poet

Callimachus Callimachus (; ) was an ancient Greek poet, scholar and librarian who was active in Alexandria during the 3rd century BC. A representative of Ancient Greek literature of the Hellenistic period, he wrote over 800 literary works in a wide varie ...

during a public evening ceremony. In Callimachus' poem, '' Aetia'' (composed around that time), Berenice dedicated her tresses "to all the gods". In Poem 66, the Latin translation by the Roman poet Catullus, and in

Hyginus Gaius Julius Hyginus (; 64 BC – AD 17) was a Latin author, a pupil of the scholar Alexander Polyhistor, and a freedman of Caesar Augustus. He was elected superintendent of the Palatine library by Augustus according to Suetonius' ''De Grammati ...

' ''

De Astronomica ''De Astronomica'', or the ''Astronomy'', also known as ''Poeticon Astronomicon'', is a book of stories whose text is attributed to "Hyginus", though the true authorship is disputed. During the Renaissance, the work was attributed to the Roman ...

'', she dedicated her tresses to

Aphrodite Aphrodite ( ; grc-gre, Ἀφροδίτη, Aphrodítē; , , ) is an ancient Greek goddess associated with love, lust, beauty, pleasure, passion, and procreation. She was syncretized with the Roman goddess . Aphrodite's major symbols inclu ...

and placed them in the temple of Arsinoe II (identified after Berenice's death with Aphrodite) at Zephyrium. According to ''De astronomica'', by the next morning the tresses had disappeared. Conon proposed that Aphrodite had placed the tresses in the sky as an acknowledgement of Berenice's sacrifice. Callimachus called the asterism ''plokamos Berenikēs'' or ''bostrukhon Berenikēs'' in Greek, translated into Latin as "Coma Berenices" by Catullus. Hipparchus and

Geminus Geminus of Rhodes ( el, Γεμῖνος ὁ Ῥόδιος), was a Greek astronomer and mathematician, who flourished in the 1st century BC. An astronomy work of his, the ''Introduction to the Phenomena'', still survives; it was intended as an int ...

also recognized it as a distinct constellation. Eratosthenes called it "Berenice's Hair" and "

Ariadne Ariadne (; grc-gre, Ἀριάδνη; la, Ariadne) was a Cretan princess in Greek mythology. She was mostly associated with mazes and labyrinths because of her involvement in the myths of the Minotaur and Theseus. She is best known for havi ...

's Hair", considering it part of the constellation Leo. Similarly,

Ptolemy Claudius Ptolemy (; grc-gre, Πτολεμαῖος, ; la, Claudius Ptolemaeus; AD) was a mathematician, astronomer, astrologer, geographer, and music theorist, who wrote about a dozen scientific treatises, three of which were of importance ...

did not include it among his 48 constellations in the '' Almagest''; considering it part of Leo and calling it ''Plokamos''. Coma Berenices became popular during the 16th century. In 1515, a set of gores by

Johannes Schöner Johannes Schöner (16 January 1477, in Karlstadt am Main – 16 January 1547, in the Free Imperial City of Nuremberg) (aka, Johann Schönner, Johann Schoener, Jean Schönner, Joan Schoenerus) was a renowned and respected German polymath. It is ...

labelled the asterism ''Trica'', "hair". In 1536 it appeared on a celestial globe by Caspar Vopel, who is credited with the asterism's designation as a constellation. That year, it also appeared on a celestial map by

Petrus Apianus Petrus Apianus (April 16, 1495 – April 21, 1552), also known as Peter Apian, Peter Bennewitz, and Peter Bienewitz, was a German humanist, known for his works in mathematics, astronomy and cartography. His work on "cosmography", the field that de ...

as "Crines Berenices". In 1551, Coma Berenices appeared on a celestial globe by

with five Latin and Greek names: Cincinnus, ''caesaries'', ''πλόκαμος'', ''Berenicis crinis'' and Trica. Mercator's reputation as a cartographer ensured the constellation's inclusion on Dutch sky globes beginning in 1589.

, also credited with Coma's designation as a constellation, included it in his 1602 star catalogue. Brahe recorded fourteen stars in the constellation;

Johannes Hevelius Johannes Hevelius Some sources refer to Hevelius as Polish: * * * * * * * Some sources refer to Hevelius as German: * * * * *of the Royal Society * (in German also known as ''Hevel''; pl, Jan Heweliusz; – 28 January 1687) was a councillor ...

increased its number to twenty-one, and

John Flamsteed John Flamsteed (19 August 1646 – 31 December 1719) was an English astronomer and the first Astronomer Royal. His main achievements were the preparation of a 3,000-star catalogue, ''Catalogus Britannicus'', and a star atlas called '' Atlas C ...

to forty-three. Coma Berenices also appeared in Johann Bayer's 1603 ''

Uranometria ''Uranometria'' is a star atlas produced by Johann Bayer. It was published in Augsburg in 1603 by Christoph Mangle (''Christophorus Mangus'') under the full title ''Uranometria: omnium asterismorum continens schemata, nova methodo delineata, a ...

'', and a few other 17th-century celestial maps followed suit. Coma Berenices and the now-obsolete Antinous are considered the first post-Ptolemaic constellations depicted on a celestial globe. With Antinous, Coma Berenices exemplified a trend in astronomy in which globe- and map-makers continued to rely on the ancients for data. This trend ended at the turn of the 16th century with observations of the southern sky and the work of Tycho Brahe. Before the 18th century Coma Berenices was known in English by several names, including "Berenice's Bush" and "Berenice's

periwig A wig is a head or hair accessory made from human hair, animal hair, or synthetic fiber. The word wig is short for periwig, which makes its earliest known appearance in the English language in William Shakespeare's ''The Two Gentlemen of Verona' ...

". The earliest-known English name, "Berenices haire", dates to 1601. By 1702 the constellation was known as Coma Berenices, and appears as such in the 1731 '' Universal Etymological English Dictionary''.

Non-Western astronomy

Coma Berenices was known to the

Akkadians The Akkadian Empire () was the first ancient empire of Mesopotamia after the long-lived civilization of Sumer. It was centered in the city of Akkad () and its surrounding region. The empire united Akkadian and Sumerian speakers under one rul ...

as Ḫegala. In

Babylonian astronomy Babylonian astronomy was the study or recording of celestial objects during the early history of Mesopotamia. Babylonian astronomy seemed to have focused on a select group of stars and constellations known as Ziqpu stars. These constellations ...

a star, known as ḪÉ.GÁL-''a''-''a'' (translated as "which is before it") or MÚL.ḪÉ.GÁL-''a''-''a'', is tentatively considered part of Coma Berenices. It was also argued that Coma Berenices appears in Egyptian Ramesside star clocks as ''sb3w ꜥš3w'', meaning "many stars". In Arabic astronomy Coma Berenices was known as ''Al-Dafira'' and ''Al-Hulba'' (translations of Ptolemaic ''Plokamos''), forming the tuft of the constellation Leo and including most of the Flamsteed-designated stars (particularly 12, 13, 14, 16, 17, 18 and

21 Comae Berenices 21 Comae Berenices is a variable star in the northern constellation of Coma Berenices. It has the variable star designation UU Comae Berenices, while 21 Comae Berenices is the Flamsteed designation. About According to R. H. Allen, En ...

Ulugh Beg Mīrzā Muhammad Tāraghay bin Shāhrukh ( chg, میرزا محمد طارق بن شاہ رخ, fa, میرزا محمد تراغای بن شاہ رخ), better known as Ulugh Beg () (22 March 1394 – 27 October 1449), was a Timurid sultan, as ...

, however, regarded ''Al-Dafira'' as consisting of two stars, 7 and 23 Comae Berenices. The North American Pawnee people depicted Coma Berenices as ten faint stars on a tanned elk-skin star map dated to at least the 17th century. In the South American Kalina mythology, the constellation was known as ''ombatapo'' (face). The constellation was also recognized by several Polynesian peoples. The people of

Tonga Tonga (, ; ), officially the Kingdom of Tonga ( to, Puleʻanga Fakatuʻi ʻo Tonga), is a Polynesian country and archipelago. The country has 171 islands – of which 45 are inhabited. Its total surface area is about , scattered over in ...

had four names for Coma Berenices: ''Fatana-lua'', ''Fata-olunga'', ''Fata-lalo'' and ''Kapakau-o-Tafahi''. The Boorong people called the constellation ''Tourt-chinboiong-gherra'', and saw it as a small flock of birds drinking rainwater from a puddle in the

crotch In humans, the crotch is the bottom of the pelvis (the region of the body where the legs join the torso) and is often considered to include the groin and genitals. Etymology ''Crotch'' is derived from ''crutch''; it "was first used in 1539 to ...

of a tree. The people of the

Pukapuka Pukapuka, formerly Danger Island, is a coral atoll in the northern group of the Cook Islands in the Pacific Ocean. It is one of most remote islands of the Cook Islands, situated about northwest of Rarotonga. On this small island, an ancient ...

atoll may have called it ''Te Yiku-o-te-kiole'', although sometimes this name is associated with

Ursa Major Ursa Major (; also known as the Great Bear) is a constellation in the northern sky, whose associated mythology likely dates back into prehistory. Its Latin name means "greater (or larger) bear," referring to and contrasting it with nearby Ursa ...

Characteristics

Coma Berenices is bordered by Boötes to the east, Canes Venatici to the north, Leo to the west and Virgo to the south. Covering 386.5 square degrees and 0.937% of the night sky, it ranks 42nd of the 88 constellations by area. The three-letter abbreviation for the constellation, as adopted by the

International Astronomical Union The International Astronomical Union (IAU; french: link=yes, Union astronomique internationale, UAI) is a nongovernmental organisation with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreac ...

in 1922, is "Com". The official constellation boundaries, as set by Belgian astronomer

Eugène Delporte Eugene is a common male given name that comes from the Greek εὐγενής (''eugenēs''), "noble", literally "well-born", from εὖ (''eu''), "well" and γένος (''genos''), "race, stock, kin".equatorial coordinate system The equatorial coordinate system is a celestial coordinate system widely used to specify the positions of celestial objects. It may be implemented in spherical or rectangular coordinates, both defined by an origin at the centre of Earth, a fu ...

, the right ascension coordinates of these borders lie between and , and the declination coordinates are between +13.30° and +33.31°. Coma Berenices is wholly visible to observers north of latitude 56°S. and the constellation's midnight culmination occurs on 2 April.

Features

Although it is not large, Coma Berenices contains one galactic supercluster, two galactic clusters, one star cluster and eight

Messier object The Messier objects are a set of 110 astronomical objects catalogued by the French astronomer Charles Messier in his ''Catalogue des Nébuleuses et des Amas d'Étoiles'' (''Catalogue of Nebulae and Star Clusters''). Because Messier was only in ...

s (including several

globular cluster A globular cluster is a spheroidal conglomeration of stars. Globular clusters are bound together by gravity, with a higher concentration of stars towards their centers. They can contain anywhere from tens of thousands to many millions of membe ...

s). These objects can be seen with minimal obscuration by dust because the constellation is not in the direction of the

galactic plane The galactic plane is the plane on which the majority of a disk-shaped galaxy's mass lies. The directions perpendicular to the galactic plane point to the galactic poles. In actual usage, the terms ''galactic plane'' and ''galactic poles'' usual ...

. Because of that, there are few open clusters (except for the Coma Berenices Cluster, which dominates the northern part of the constellation), diffuse nebulae or

planetary nebula A planetary nebula (PN, plural PNe) is a type of emission nebula consisting of an expanding, glowing shell of ionized gas ejected from red giant stars late in their lives. The term "planetary nebula" is a misnomer because they are unrelate ...

e. Coma Berenices contains the North Galactic Pole at right ascension and declination (epoch J2000.0).

Stars

Brightest stars

Coma Berenices is not particularly bright, as none of its stars are brighter than fourth

, although there are 66 stars brighter than or equal to

apparent magnitude Apparent magnitude () is a measure of the brightness of a star or other astronomical object observed from Earth. An object's apparent magnitude depends on its intrinsic luminosity, its distance from Earth, and any extinction of the object's ...

6.5. The constellation's brightest star is

Beta Comae Berenices Beta Comae Berenices (β Comae Berenices, β Com) is a main sequence dwarf star in the northern constellation of Coma Berenices. It is located at a distance of about from Earth. The Greek letter beta (β) usually indicates that the sta ...

(43 Comae Berenices in

Flamsteed designation A Flamsteed designation is a combination of a number and constellation name that uniquely identifies most naked eye stars in the modern constellations visible from southern England. They are named for John Flamsteed who first used them while co ...

, occasionally known as Al-Dafira), at magnitude 4.2 and with a high proper motion. In Coma Berenices' northeastern region, it is 29.95 ± 0.10 light-years from Earth. A

solar analog Solar-type star, solar analogs (also analogues), and solar twins are stars that are particularly similar to the Sun. The stellar classification is a hierarchy with solar twin being most like the Sun followed by solar analog and then solar-type ...

, it is a yellow-hued

F-type main-sequence star An F-type main-sequence star (F V) is a main-sequence, hydrogen-fusing star of spectral type F and luminosity class V. These stars have from 1.0 to 1.4 times the mass of the Sun and surface temperatures between 6,000 and 7,600 K.Tables VII ...

with a

spectral class In astronomy, stellar classification is the classification of stars based on their spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a prism or diffraction grating into a spectrum exhibiting the ...

of F9.5V B. Beta Comae Berenices is around 36% brighter,. See Table 10. and 15% more massive than the

Sun The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...

, ''Note:'' see VizieR catalogu
J/ApJS/168/297
and with a radius 10% larger. The second-brightest star in Coma Berenices is the 4.3-magnitude, bluish Alpha Comae Berenices (42 Comae Berenices), with the

proper name A proper noun is a noun that identifies a single entity and is used to refer to that entity (''Africa'', ''Jupiter'', ''Sarah'', ''Microsoft)'' as distinguished from a common noun, which is a noun that refers to a class of entities (''continent, ...

Diadem, in the southeastern part of the constellation. Despite its Alpha Bayer designation, the star is dimmer than Beta Comae Berenices, being one of the cases where designation does not correspond to the brightest star. It is a double star, with the spectral classes of F5V and F6V. The star system is 58.1 ± 0.9 light-years from Earth. Gamma Comae Berenices (15 Comae Berenices) is an orange-hued

giant star A giant star is a star with substantially larger radius and luminosity than a main-sequence (or ''dwarf'') star of the same surface temperature.Giant star, entry in ''Astronomy Encyclopedia'', ed. Patrick Moore, New York: Oxford University Press ...

with a magnitude of 4.4 and a spectral class of K1III C. In the southwestern part of the constellation, it is 169 ± 2 light-years from Earth, Estimated to be around 1.79 times as massive as the Sun, it has expanded to around 10 times its radius.HD 108381
Accessed on line October 12, 2010. It is the brightest star in the

. With Alpha Comae Berenices and Beta Comae Berenices, Gamma Comae Berenices forms a 45-degree isosceles triangle from which Berenice's imaginary tresses hang.

Star systems

The star systems of Coma Berenices include

binary Binary may refer to: Science and technology Mathematics * Binary number, a representation of numbers using only two digits (0 and 1) * Binary function, a function that takes two arguments * Binary operation, a mathematical operation that ta ...

, double and triple stars.

(

Kissin) is a

close binary A binary star is a system of two stars that are gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved using a telescope as separate stars, in wh ...

with nearly equal components and an

orbital period The orbital period (also revolution period) is the amount of time a given astronomical object takes to complete one orbit around another object. In astronomy, it usually applies to planets or asteroids orbiting the Sun, moons orbiting planets ...

of 26 years. The system is 272 ± 3 light-years away. The Coma Cluster contains at least eight

spectroscopic binaries A binary star is a system of two stars that are gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved using a telescope as separate stars, in w ...

, and the constellation has seven

eclipsing binaries A binary star is a system of two stars that are gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved using a telescope as separate stars, in wh ...

: CC, DD, EK, RW, RZ, SS and UX Comae Berenices. There are over thirty double stars in Coma Berenices, including 24 Comae Berenices with contrasting colors. Its primary is an orange-hued giant star with a magnitude of 5.0, 610 light-years from Earth, and its secondary is a blue-white-hued star with a magnitude of 6.6. Triple stars include

12 Comae Berenices 12 Comae Berenices is a binary star system in the northern constellation of Coma Berenices. It is the brightest member of the Coma Cluster and is visible to the naked eye with an apparent visual magnitude of 4.80. Although listed as a su ...

17 Comae Berenices 17 Comae Berenices (17 Com) is a multiple star system in the northern constellation of Coma Berenices. The brighter component, 17 Com A, is a naked eye star with an apparent visual magnitude of 5.2. It has a faint companion of magnitude ...

, KR Comae Berenices and Struve 1639.

Variable stars

Over 200

variable star A variable star is a star whose brightness as seen from Earth (its apparent magnitude) changes with time. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are classified as e ...

s are known in Coma Berenices, although many are obscure. Alpha Comae Berenices is a possible

Algol variable Algol variables or Algol-type binaries are a class of eclipsing binary stars that are similar to the prototype member of this class, β Persei (Beta Persei, Algol). An Algol binary is a system where both stars are near-spherical such that ...

, which varies from magnitude 8.14 to 8.33 over a period of 2.4 days, is the prototype for the FK Comae Berenices class of variable stars and the star in which the " flip-flop phenomenon" was discovered. FS Comae Berenices is a semi-regular variable, a red giant with a period of about two months whose magnitude varies between 6.1 and 5.3. R Comae Berenices is a

Mira variable Mira variables (named for the prototype star Mira) are a class of pulsating stars characterized by very red colours, pulsation periods longer than 100 days, and amplitudes greater than one magnitude in infrared and 2.5 magnitude at visual wavele ...

with a maximum magnitude of almost 7. There are 123 RR Lyrae variables in the constellation, with many in the M53 cluster. One of these stars, TU Comae Berenices, may have a

binary system A binary system is a system of two astronomical bodies which are close enough that their gravitational attraction causes them to orbit each other around a barycenter ''(also see animated examples)''. More restrictive definitions require that th ...

. The M100 galaxy contains about twenty

Cepheid variable A Cepheid variable () is a type of star that pulsates radially, varying in both diameter and temperature and producing changes in brightness with a well-defined stable period and amplitude. A strong direct relationship between a Cepheid vari ...

s, which were observed by the

Hubble Space Telescope The Hubble Space Telescope (often referred to as HST or Hubble) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the first space telescope, but it is one of the largest and most vers ...

. Coma Berenices also contains Alpha² Canum Venaticorum variables, such as

13 Comae Berenices 13 Comae Berenices is a probable binary star system in the northern constellation of Coma Berenices. It has an apparent visual magnitude of 5.17, which is bright enough to be faintly visible to the naked eye. With an annual stellar paralla ...

and AI Comae Berenices. In 2019 scientists at Aryabhatta Research Institute of Observational Sciences announced the discovery of 28 new variable stars in Coma Berenices' globular cluster NGC 4147.

Supernovae

A number of supernovae have been discovered in Coma Berenices. Four ( SN 1940B, SN 1969H, SN 1987E and SN 1999gs) were in the NGC 4725 galaxy, and another four were discovered in the M99 galaxy (NGC 4254): SN 1967H, SN 1972Q, SN 1986I and SN 2014L. Five were discovered in the M100 galaxy (NGC 4321): SN 1901B, SN 1914A, SN 1959E, SN 1979C and SN 2006X. SN 1940B, discovered on 5 May 1940, was the first observed type II supernova. SN 2005ap, discovered on 3 March 2005, is the second-brightest-known supernova to date with a peak

absolute magnitude Absolute magnitude () is a measure of the luminosity of a celestial object on an inverse logarithmic astronomical magnitude scale. An object's absolute magnitude is defined to be equal to the apparent magnitude that the object would have if it ...

of about −22.7. Due to its great distance from Earth (4.7 billion light-years), it was not visible to the naked eye and was discovered telescopically. SN 1979C, discovered in 1979, retained its original

X-ray An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nb ...

brightness for 25 years despite fading in visible light.

Other stars

Coma Berenices also contains the

neutron star A neutron star is the collapsed core of a massive supergiant star, which had a total mass of between 10 and 25 solar masses, possibly more if the star was especially metal-rich. Except for black holes and some hypothetical objects (e.g. w ...

RBS 1223 and the pulsar PSR B1237+25. RBS 1223 is a member of

the Magnificent Seven ''The Magnificent Seven'' is a 1960 American Western film directed by John Sturges. The screenplay by William Roberts is a remake – in an Old West–style – of Akira Kurosawa's 1954 Japanese film ''Seven Samurai'' (itself initially relea ...

, a group of young neutron stars. In 1975, the first extra-solar source of

extreme ultraviolet Extreme ultraviolet radiation (EUV or XUV) or high-energy ultraviolet radiation is electromagnetic radiation in the part of the electromagnetic spectrum spanning wavelengths from 124 nm down to 10 nm, and therefore (by the Planck–E ...

, the white dwarf HZ 43, was discovered in Coma Berenices. In 1995, there was a very rare outburst of the WZ Sagittae-type dwarf nova AL Comae Berenices. A June 2003 outburst from GO Comae Berenices, an SU Ursae Majoris-type dwarf nova, was photometrically observed.

Exoplanets

Coma Berenices has seven known exoplanets. One, HD 108874 b, has Earth-like insolation. WASP-56 is a sun-like star of spectral type G6 and apparent magnitude 11.48 with a planet 0.6 the mass of

Jupiter Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but slightly less than one-thousandth t ...

that has a period of 4.6 days.

Star clusters

Coma Star Cluster

The

represents Berenice's sacrificed tresses and as a naked eye object has been known since antiquity, appearing in Ptolemy's '' Almagest''. It doesn't have a Messier or NGC designation, but is in the Melotte catalogue of open clusters (designated Melotte 111) and is also catalogued as Collinder 256. It is a large, diffuse open cluster of about 50 stars ranging between magnitudes five and ten, including several of Coma Berenices' stars which are visible to the naked eye. The cluster is spread over a huge region (more than five degrees across) near Gamma Comae Berenices. It has such a large apparent size because it is relatively close, only 280 light-years or 86 parsecs away.

Globular clusters

M53 (NGC 5024) is a

which was discovered independently by Johann Elert Bode in 1775 and

Charles Messier Charles Messier (; 26 June 1730 – 12 April 1817) was a French astronomer. He published an astronomical catalogue consisting of 110 nebulae and star clusters, which came to be known as the ''Messier objects''. Messier's purpose ...

in February 1777;

William Herschel Frederick William Herschel (; german: Friedrich Wilhelm Herschel; 15 November 1738 – 25 August 1822) was a German-born British astronomer and composer. He frequently collaborated with his younger sister and fellow astronomer Caroline ...

was the first to resolve it into stars. The magnitude-7.7 cluster is 56,000 light-years from Earth. Only 1° away is NGC 5053, a globular cluster with a sparser nucleus of stars. Its total luminosity is the equivalent of about 16,000 suns, one of the lowest luminosities of any globular cluster. It was discovered by William Herschel in 1784. NGC 4147 is a somewhat dimmer globular cluster, with a much-smaller

apparent size The angular diameter, angular size, apparent diameter, or apparent size is an angular distance describing how large a sphere or circle appears from a given point of view. In the vision sciences, it is called the visual angle, and in optics, it is ...

and an apparent magnitude of 10.7.

Galaxies

Coma Supercluster

The

, itself part of the Coma Filament, contains the Coma and Leo Cluster of galaxies. The Coma Cluster ( Abell 1656) is 230 to 300 million light-years away. It is one of the largest-known clusters, with at least 10,000 galaxies (mainly elliptical, with a few spiral galaxies). Due to its distance from Earth, most of the galaxies are visible only through large telescopes. Its brightest members are NGC 4874 and

NGC 4889 NGC 4889 (also known as Caldwell 35) is an E4 supergiant elliptical galaxy. It was discovered in 1785 by the British astronomer Frederick William Herschel I, who catalogued it as a bright, nebulous patch. The brightest galaxy within the northern ...

, both with a magnitude of 13; most others are magnitude 15 or dimmer. NGC 4889 is a giant elliptical galaxy with one of the largest-known black holes (21 billion solar masses), and

NGC 4921 NGC 4921 is a barred spiral galaxy in the Coma Cluster, located in the constellation Coma Berenices. It is about 320 million light-years from Earth. The galaxy has a nucleus with a bar structure that is surrounded by a distinct ring of dust th ...

is the cluster's brightest spiral galaxy. After observing the Coma Cluster, astronomer Fritz Zwicky first postulated the existence of

dark matter Dark matter is a hypothetical form of matter thought to account for approximately 85% of the matter in the universe. Dark matter is called "dark" because it does not appear to interact with the electromagnetic field, which means it does not a ...

during the 1930s. The massive galaxy

Dragonfly 44 Dragonfly 44 is an ultra diffuse galaxy in the Coma Cluster. This galaxy is well-known because observations of the velocity dispersion in 2016 suggested a mass of about one trillion solar masses, about the same as the Milky Way. This mass was con ...

discovered in 2015 was found to consist almost entirely of dark matter. Its mass is very similar to that of the

Milky Way The Milky Way is the galaxy that includes our Solar System, with the name describing the galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked eye. ...

, but it emits only 1% of the light emitted by the Milky Way. NGC 4676, sometimes called the Mice Galaxies, is a pair of interacting galaxies 300 million light-years from Earth. Its progenitor galaxies were spiral, and astronomers estimate that they had their closest approach about 160 million years ago. That approach triggered large regions of star formation in both galaxies, with long "tails" of dust, stars and gas. The two progenitor galaxies are predicted to interact significantly at least one more time before they merge into a larger, probably- elliptical galaxy.

Virgo Cluster

25 years of stunning definition Messier 100

Coma Berenices contains the northern portion of the

Virgo Cluster The Virgo Cluster is a large cluster of galaxies whose center is 53.8 ± 0.3 Mly (16.5 ± 0.1 Mpc) away in the constellation Virgo. Comprising approximately 1,300 (and possibly up to 2,000) member galaxies, the cluster forms the heart of the la ...

(also known as the Coma–Virgo Cluster), about 60 million light-years away. The portion includes six Messier galaxies. M85 (NGC 4382), considered elliptical or lenticular, is one of the cluster's brighter members at magnitude nine. M85 is interacting with the spiral galaxy NGC 4394 and the elliptical galaxy MCG-3-32-38. However, it is relatively isolated from the rest of the cluster. M88 (NGC 4501) is a multi-arm spiral galaxy seen at about 30° from edge-on. It has a highly-regular shape with well-developed, symmetrical arms. Among the first galaxies recognized as spiral, it has a

supermassive black hole A supermassive black hole (SMBH or sometimes SBH) is the largest type of black hole, with its mass being on the order of hundreds of thousands, or millions to billions of times the mass of the Sun (). Black holes are a class of astronomical ob ...

in its center. M91 (NGC 4548), a

barred spiral galaxy A barred spiral galaxy is a spiral galaxy with a central bar-shaped structure composed of stars. Bars are found in about two thirds of all spiral galaxies, and generally affect both the motions of stars and interstellar gas within spiral galaxies ...

with a bright, diffuse nucleus, is the faintest object in Messier's catalog at magnitude 10.2. M98 (NGC 4192), a bright, elongated spiral galaxy seen nearly edge-on, appears elliptical because of its unusual angle. The magnitude-10 galaxy has no redshift. M99 (NGC 4254) is a spiral galaxy seen face-on. Like M98 it is of magnitude-10 and has an unusually long arm on its west side. Four supernovae have been observed in the galaxy. M100 (NGC 4321), a magnitude-nine spiral galaxy seen face-on, is one of the cluster's brightest. Photographs reveal a brilliant core, two prominent spiral arms, an array of secondary arms and several

dust lane A dust lane consists of a relatively dense, obscuring clouds of interstellar dust, observed as a dark swath against the background of a brighter object(s), especially a galaxy. These dust lanes can usually be seen in spiral galaxies, such as ...

Other galaxies

M64 (NGC 4826) is known as the

Black Eye Galaxy The Black Eye Galaxy (also called Sleeping Beauty Galaxy or Evil Eye Galaxy and designated Messier 64, M64, or NGC 4826) is a relatively isolated spiral galaxy 17 million light-years away in the mildly northern constellation of Coma Bere ...

because of the prominent dark

in front of the galaxy's bright nucleus. Also known as the Sleeping Beauty and Evil Eye galaxy, it is about 17.3 million light-years away. Recent studies indicate that the

interstellar gas In astronomy, the interstellar medium is the matter and radiation that exist in the space between the star systems in a galaxy. This matter includes gas in ionic, atomic, and molecular form, as well as dust and cosmic rays. It fills interstella ...

in the galaxy's outer regions rotates in the opposite direction from that in the inner regions, leading astronomers to believe that at least one satellite galaxy collided with it less than a billion years ago. All other evidence of the smaller galaxy has been assimilated. At the interface between the clockwise- and counterclockwise-rotating regions are many new nebulae and young stars.

NGC 4314 NGC 4314 is a barred spiral galaxy approximately 53 million light-years away in the northern constellation of Coma Berenices. It is positioned around 3° to the north and slightly west of the star Gamma Comae Berenices and is visible in a sm ...

is a face-on

at a distance of 40 million light-years. It is unique for its region of intense star formation, creating a ring around its nucleus which was discovered by the

. The galaxy's prodigious star formation began five million years ago, in a region with a diameter of 1,000 light-years. The core's structure is also unique because the galaxy has spiral arms which feed gas into the bar. NGC 4414 is an unbarred spiral flocculent galaxy about 62 million light-years away. It is one of the closest flocculent spiral galaxies. NGC 4565 is an edge-on spiral galaxy which appears superimposed on the Virgo Cluster. NGC 4565 has been nicknamed the Needle Galaxy because when seen in full, it appears as a narrow streak of light. Like many edge-on spiral galaxies, it has a prominent dust lane and a central bulge. NGC 4565 has at least two satellite galaxies, and one of them is interacting with it. NGC 4651, about the size of the

, has tidal

stellar stream In astronomy, stellar kinematics is the observational study or measurement of the kinematics or motions of stars through space. Stellar kinematics encompasses the measurement of stellar velocities in the Milky Way and its satellites as well as t ...

s gravitationally stripped from a smaller, satellite galaxy. It is about 62 million light-years away. It is located on the outskirts of the cluster, and is also known as the Umbrella Galaxy. Unlike the other spiral galaxies in the cluster, NGC 4651 is rich in neutral hydrogen, which also extends beyond the

optical Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultravio ...

disk. Its star formation is typical for a galaxy of its type. Spiral galaxy Malin 1 discovered in 1986 is the first-known giant low-surface-brightness galaxy. With UGC 1382, it is also one of the largest low-surface-brightness galaxies. In 2006 a

dwarf galaxy A dwarf galaxy is a small galaxy composed of about 1000 up to several billion stars, as compared to the Milky Way's 200–400 billion stars. The Large Magellanic Cloud, which closely orbits the Milky Way and contains over 30 billion stars, is so ...

, also named Coma Berenices, was discovered in the constellation from data obtained by the Sloan Digital Sky Survey. The galaxy is a faint satellite of the Milky Way. It is one of the faintest satellites of the

Galaxy] - its integrated luminosity is about times that of the Sun (absolute

visible magnitude Apparent magnitude () is a measure of the brightness of a star or other astronomical object observed from Earth. An object's apparent magnitude depends on its intrinsic luminosity, its distance from Earth, and any extinction of the object's lig ...

of about −4.1), which is lower than many

s. A high mass to light ratio may mean that the satellite has large amounts of

. File:NGC 4789A, a subtle swarm.jpg, Dwarf irregular galaxy NGC 4789A, alt=Diffuse galaxy File:Needle Galaxy 4565.jpeg, alt=Galaxy resembling an angled needle, NGC 4565 (Needle Galaxy) File:Small ngc4651.jpg, alt=Spiral galaxy with streams of light, NGC 4651, with umbrella-shaped stellar streams

Quasars

HS 1216+5032 is a bright, gravitationally lensed pair of quasars. W Comae Berenices (or ON 231), a blazar in the constellation's northwest, was originally designated a variable star and later found to be a

BL Lacertae object A BL Lacertae object or BL Lac object is a type of active galactic nucleus (AGN) or a galaxy with such an AGN, named after its prototype, BL Lacertae. In contrast to other types of active galactic nuclei, BL Lacs are characterized by rapid and l ...

. As of 2009, it had the most intense gamma ray spectrum of the sixty known gamma-ray blazars.

Gamma-ray bursts

Some

gamma-ray burst In gamma-ray astronomy, gamma-ray bursts (GRBs) are immensely energetic explosions that have been observed in distant galaxies. They are the most energetic and luminous electromagnetic events since the Big Bang. Bursts can last from ten millise ...

s occurred in Coma Berenices, particularly GRB 050509B on 9 May 2005 and GRB 080607 on 7 June 2008. GRB 050509B, which lasted only 0.03 second, became the first short burst with a detected

afterglow An afterglow in meteorology consists of several atmospheric optical phenomena, with a general definition as a broad arch of whitish or pinkish sunlight in the twilight sky, consisting of the bright segment and the purple light. Purple light mai ...

Meteor shower

The Coma Berenicids meteor shower peaks around 18 January. Despite the shower's low intensity (averaging one or two meteors per hour) its meteors are some of the fastest, with speeds up to .

In culture

The hair of Berenice, by Luis Ricardo Faléro

Since Callimachus' poem, Coma Berenices has been occasionally featured in culture.

Alexander Pope Alexander Pope (21 May 1688 O.S. – 30 May 1744) was an English poet, translator, and satirist of the Enlightenment era who is considered one of the most prominent English poets of the early 18th century. An exponent of Augustan literature, ...

alludes to the legend in the ending of '' The Rape of the Lock'', in which the titular hair is placed among the stars. (The poem would go on to provide the names of some of the

moons of Uranus Uranus, the seventh planet of the Solar System, has 27 known moons, most of which are named after characters that appear in, or are mentioned in, the works of William Shakespeare and Alexander Pope. Uranus's moons are divided into three groups: t ...

.) In 1886, Spanish artist Luis Ricardo Falero created a

mezzotint Mezzotint is a monochrome printmaking process of the '' intaglio'' family. It was the first printing process that yielded half-tones without using line- or dot-based techniques like hatching, cross-hatching or stipple. Mezzotint achieves tonal ...

print personifying Coma Berenices alongside Virgo and Leo. In 1892, the Russian poet

Afanasy Fet Afanasy Afanasyevich Fet ( rus, Афана́сий Афана́сьевич Фет, p=ɐfɐˈnasʲɪj ɐfɐˈnasʲjɪvʲɪtɕ ˈfʲɛt, a=Ru-Afanasiy Afanas'yevich Fyet.oga), later known as Shenshin ( rus, Шенши́н, p=ʂɨnˈʂɨn, a=Ru-Afa ...

made the constellation the subject of his short poem, composed for the Countess Natalya Sollogub. The Swedish poet Gunnar Ekelöf wrote the lines "Your friend the comet combed his hair with the

Leonids The Leonids ( ) are a prolific meteor shower associated with the comet Tempel–Tuttle, which are also known for their spectacular meteor storms that occur about every 33 years. The Leonids get their name from the location of their radiant ...

/ Berenice let her hair hang down from the sky" in a 1933 poem. American writer and folksinger

Richard Fariña Richard George Fariña ( Spanish IPA: ) (March 8, 1937 – April 30, 1966) was an American folksinger, songwriter, poet and novelist. Early years and education Fariña was born in Brooklyn, New York, United States, the son of an Irish mother, ...

mentions Coma Berenices in his 1966 novel ''

Been Down So Long It Looks Like Up To Me ''Been Down So Long It Looks Like Up to Me'' is a novel by Richard Fariña. Parts campus novel and travelogue, the book was first published in 1966 and is largely based on Fariña's college experiences and travels. Set variously in an upstat ...

'', sardonically writing about content typical to upper-level astronomy coursework at Cornell: "It's the advanced courses give you trouble. Relativity principles, spiral nebula in Coma Berenices, that kind of hassle". The Bolivian poet,

Pedro Shimose Pedro Shimose Kawamura (born 30 March 1940) is a poet, journalist, professor and essayist from Bolivia. He has been based in Madrid, Spain since 1971. Shimose is considered one of Bolivia's most notable poets. Biography Shimose was born in 1 ...

, makes Coma Berenices the home address of his "Señorita NGC 4565" in his poem "Carta a una estrella que vive en otra constelación" ("Letter to a star who lives in another constellation"), included in his 1967 collection, "Sardonia". " The Irish poet W. B. Yeats, in his poem "Her Dream", refers to "Berenice's burning hair" being "nailed upon the night". Francisco Guerrero, a 20th-century Spanish composer, wrote an orchestral work on the constellation in 1996. In 1999 Irish artist Alice Maher made a series of four oversize drawings, entitled ''Coma Berenices'', of entwining black hair coils.

Notes

References

External links

The Deep Photographic Guide to the Constellations: Coma Berenices

* {{DEFAULTSORT:Coma Berenices Northern constellations Ptolemaic Kingdom in popular culture IAU constellations