NGC 4889

Last updated
NGC 4889
Caldwell 35.jpg
The elliptical galaxy NGC 4889
Credit: Hubble Space Telescope
Observation data (J2000.0 epoch)
Constellation Coma Berenices
Right ascension 13h 00m 08.1s [1]
Declination +27° 58′ 37″ [1]
Redshift 0.021502±0.000010 [1]
Heliocentric radial velocity 6495±13 km/s [1]
Galactocentric velocity6509±13 km/s [1]
Apparent magnitude  (V)12.9 [1]
Characteristics
Type cD; E4; Dd [1]
Size86.976 to 90.9  kpc (283,680 to 296,480  ly)
(diameter; D25.0 B-band and 2MASS K-band total isophotes) [1]
Apparent size  (V)2.9 × 1.9 moa [1]
Other designations
ZWG 160.241, DRCG 27-148, Caldwell 35, NGC 4884, UGC 8110, MCG +5-31-77, PGC 44715 [2]
References: SIMBAD: data

NGC 4889 (also known as Caldwell 35) is an E4 supergiant elliptical galaxy. [3] 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 Coma Cluster, it is located at a median distance of 94 million parsecs (308 million light years) from Earth. At the core of the galaxy is a supermassive black hole that heats the intracluster medium through the action of friction from infalling gases and dust. The gamma ray bursts from the galaxy extend out to several million light years of the cluster.

Contents

As with other similar elliptical galaxies, only a fraction of the mass of NGC 4889 is in the form of stars. They have a flattened, unequal distribution that bulges within its edge. Between the stars is a dense interstellar medium full of heavy elements emitted by evolved stars. The diffuse stellar halo extends out to one million light years in diameter. Orbiting the galaxy is a very large population of globular clusters. NGC 4889 is also a strong source of soft X-ray, ultraviolet, and radio frequency radiation.

As the largest and the most massive galaxy easily visible to Earth, NGC 4889 has played an important role in both amateur and professional astronomy, and has become a prototype in studying the dynamical evolution of other supergiant elliptical galaxies in the more distant universe.

Observation

Wide-field image of the Coma Cluster. NGC 4889 is the bright galaxy to the left. The galaxy at the right is NGC 4874, while the star above it is HD 112887 which is a foreground star and is completely unrelated to the cluster. Coma Cluster of Galaxies (visible, wide field).jpg
Wide-field image of the Coma Cluster. NGC 4889 is the bright galaxy to the left. The galaxy at the right is NGC 4874, while the star above it is HD 112887 which is a foreground star and is completely unrelated to the cluster.

NGC 4889 was not included by the astronomer Charles Messier in his famous Messier catalogue despite being an intrinsically bright object quite close to some Messier objects. The first known observation of NGC 4889 was that of Frederick William Herschel I, assisted by his sister, Caroline Lucretia Herschel, in 1785, who included it in the Catalogue of Nebulae and Clusters of Stars published a year later. In 1864, Herschel's son, John Frederick William Herschel, published the General Catalogue of Nebulae and Clusters of Stars. He included the objects catalogued by his father, including the one later to be called NGC 4889, plus others he found that were somehow missed by his father.

In 1888 the astronomer John Louis Emil Dreyer published the New General Catalogue of Nebulae and Clusters of Stars (NGC), with a total of 7,840 objects, but he erroneously duplicated the galaxy in two designations, NGC 4884 and NGC 4889. Within the following century, several projects aimed to revise the NGC catalogue, such as The NGC/IC Project, Revised New General Catalogue of Nebulae and Clusters of Stars, and the NGC 2000.0 projects, discovered the duplication. It was then decided that the object would be called by its latter designation, NGC 4889, which is in use today.

In December 1995, Patrick Caldwell Moore compiled the Caldwell catalogue, a list of 109 persistent, bright objects that were somehow missed by Messier in his catalogue. The list also includes NGC 4889, which is given the designation Caldwell 35.

Properties

Cercle rouge 100%25.svg
Coma Berenices constellation map.svg
The location of NGC 4889 (circled) in Coma Berenices

NGC 4889 is located along the high declination region of Coma Berenices, south of the constellation Canes Venatici. It can be traced by following the line from Beta Comae Berenices to Gamma Comae Berenices. With an apparent magnitude of 11.4, it can be seen by telescopes with 12 inch aperture, but its visibility is greatly affected by light pollution due to glare of the light from Beta Comae Berenices. However, under very dark, moonless skies, it can be seen by small telescopes as a faint smudge, but larger telescopes are needed in order to see the galaxy's halo.

In the updated Hubble sequence galaxy morphological classification scheme by the French astronomer Gérard de Vaucouleurs in 1959, NGC 4889 is classified as an E4 type galaxy, which means it has a flat distribution of stars within its width. It is also classified as a cD galaxy, a giant type of D galaxy, a classification devised by the American astronomer William Wilson Morgan in 1958 for galaxies with an elliptical-shaped nucleus surrounded by an immense, diffuse, dustless, extended halo.

NGC 4889 is far enough that its distance can be measured using redshift. With the redshift of 0.0266 as derived from the Sloan Digital Sky Survey, and the Hubble constant as determined in 2013 by the ESA COBRAS/SAMBA/Planck Surveyor translates its distance of 94 Mpc (308 million light years) from Earth.

NGC 4889 is probably the largest and the most massive galaxy out to the radius of 100 Mpc (326 million light years) of the Milky Way. The galaxy has an effective radius which extends at 2.9 arcminutes of the sky, translating to a diameter of 239,000 light years, about the size of the Andromeda Galaxy. In addition it has an immense diffuse light halo extending to 17.8 arcminutes, roughly half the angular diameter of the Sun, translating to 1.3 million light years in diameter.

Along with its large size, NGC 4889 may also be extremely massive. If we take the Milky Way as the standard of mass, it may be close to 8 trillion solar masses. However, as NGC 4889 is a spheroid, and not a flat spiral, it has a three-dimensional profile, so it may be as high as 15 trillion solar masses. However, as for elliptical galaxies, only a small fraction of the mass of NGC 4889 is in the form of stars that radiate energy.

Components

Elliptical galaxy NGC 4889 in front of hundreds of background galaxies. NGC 4889 HST.png
Elliptical galaxy NGC 4889 in front of hundreds of background galaxies.

Giant elliptical galaxies like NGC 4889 are believed to be the result of multiple mergers of smaller galaxies. There is now little dust remaining to form the diffuse nebulae where new stars are created, so the stellar population is dominated by old, population II stars that contain relatively low abundances of elements other than hydrogen and helium. The egg-like shape of this galaxy is maintained by random orbital motions of its member stars, in contrast to the more orderly rotational motions found in a spiral galaxy such as the Milky Way. NGC 4889 has 15,800 globular clusters, more than Messier 87, which has 12,000. This is half of NGC 4874's collection of globular clusters, which has 30,000 globular clusters.

The space between the stars in the galaxy is filled with a diffuse interstellar medium of gas, which has been filled by the elements ejected from stars as they passed beyond the end of their main sequence lifetime. Carbon and nitrogen are being continuously supplied by intermediate mass stars as they pass through the asymptotic giant branch. The heavier elements from oxygen to iron are primarily produced by supernova explosions within the galaxy. The interstellar medium is continuously heated by the emission of in-falling gases towards its central SMBH.

Supermassive black hole

On December 5, 2011, astronomers measured the velocity dispersion of the central regions of two massive galaxies, NGC 4889, and the other being NGC 3842 in the Leo Cluster. According to the data of the study, they found out the central supermassive black hole of NGC 4889 is 5,200 times more massive than the central black hole of the Milky Way, or equivalent to 2.1×1010 (21 billion) solar masses (best fit of data; possible range is from 6 billion to 37 billion solar masses). [5] This makes it one of the most massive black holes on record. The diameter of the black hole's immense event horizon is about 20 to 124 billion kilometers, 2 to 12 times the diameter of Pluto's orbit. The ionized medium detected around the black hole suggests that NGC 4889 may have been a quasar in the past. It is quiescent, presumably because it has already absorbed all readily available matter. [6]

Environment

The Coma Cluster taken using data from the Sloan Digital Sky Survey and the Spitzer Space Telescope. NGC 4889 is at the center. Ssc2007-10a1.jpg
The Coma Cluster taken using data from the Sloan Digital Sky Survey and the Spitzer Space Telescope. NGC 4889 is at the center.

NGC 4889 lies at the center of the component A of the Coma Cluster, a giant cluster of 2,000 galaxies which it shares with NGC 4874, although NGC 4889 is sometimes referred as the cluster center, and it has been called by its other designation A1656-BCG. The total mass of the cluster is estimated to be on the order of 4×1015 M☉.

The Coma Cluster is located at exactly the center of the Coma Supercluster, which is one of the nearest superclusters to the Laniakea Supercluster. The Coma Supercluster itself is within the CfA Homunculus, the center of the CfA2 Great Wall, the nearest galaxy filament to Earth and one of the largest structures in the known universe.

Notes

  1. 1 2 3 4 5 6 7 8 9 "NASA/IPAC Extragalactic Database". Results for NGC 4889. Retrieved 2015-01-04.
  2. ↑ "Revised NGC Data for NGC 4889". spider.seds.org. Retrieved 2015-10-13.
  3. ↑ Jacobsen, Den (2006). "Abell 1656, NGC 4889, NGC 4874". astrophoto.net. Archived from the original on 2008-11-18. Retrieved 2008-08-09.
  4. ↑ "The sleeping giant" . Retrieved 16 February 2016.
  5. ↑ McConnell, Nicholas J. (2011-12-08). "Two ten-billion-solar-mass black holes at the centres of giant elliptical galaxies". Nature. 480 (7376): 215–218. arXiv: 1112.1078 . Bibcode:2011Natur.480..215M. doi:10.1038/nature10636. PMID   22158244. S2CID   4408896.
  6. ↑ "Astronomers find supermassive black hole in giant galaxy 300 million light years away | Fox News". Fox News. 2016-02-18. Retrieved 2016-02-20.

Related Research Articles

<span class="mw-page-title-main">Galaxy</span> Large gravitationally bound system of stars and interstellar matter

A galaxy is a system of stars, stellar remnants, interstellar gas, dust, and dark matter bound together by gravity. The word is derived from the Greek galaxias (γαλαξίας), literally 'milky', a reference to the Milky Way galaxy that contains the Solar System. Galaxies, averaging an estimated 100 billion stars, range in size from dwarfs with less than a hundred million stars, to the largest galaxies known – supergiants with one hundred trillion stars, each orbiting its galaxy's center of mass. Most of the mass in a typical galaxy is in the form of dark matter, with only a few percent of that mass visible in the form of stars and nebulae. Supermassive black holes are a common feature at the centres of galaxies.

<span class="mw-page-title-main">Coma Berenices</span> Constellation in the northern hemisphere

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, between Leo and Boötes, and it is visible in both hemispheres. Its name means "Berenice's Hair" in Latin and refers to Queen Berenice II of Egypt, who sacrificed her long hair as a votive offering. 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 and Tycho Brahe. It is the only modern constellation named for a historic person.

<span class="mw-page-title-main">Messier 87</span> Elliptical galaxy in the Virgo Galaxy Cluster

Messier 87 is a supergiant elliptical galaxy in the constellation Virgo that contains several trillion stars. One of the largest and most massive galaxies in the local universe, it has a large population of globular clusters—about 15,000 compared with the 150–200 orbiting the Milky Way—and a jet of energetic plasma that originates at the core and extends at least 1,500 parsecs, traveling at a relativistic speed. It is one of the brightest radio sources in the sky and a popular target for both amateur and professional astronomers.

<span class="mw-page-title-main">Pinwheel Galaxy</span> Galaxy in the constellation Ursa Major

The Pinwheel Galaxy is a face-on spiral galaxy 21 million light-years away from Earth in the constellation Ursa Major. It was discovered by Pierre Méchain in 1781 and was communicated that year to Charles Messier, who verified its position for inclusion in the Messier Catalogue as one of its final entries.

<span class="mw-page-title-main">Lists of astronomical objects</span>

This is a list of lists, grouped by type of astronomical object.

<span class="mw-page-title-main">Sombrero Galaxy</span> Galaxy in the constellation Virgo

The Sombrero Galaxy is a peculiar galaxy of unclear classification in the constellation borders of Virgo and Corvus, being about 9.55 megaparsecs from the Milky Way galaxy. It is a member of the Virgo II Groups, a series of galaxies and galaxy clusters strung out from the southern edge of the Virgo Supercluster. It has an isophotal diameter of approximately 29.09 to 32.32 kiloparsecs, making it slightly bigger in size than the Milky Way.

<span class="mw-page-title-main">Omega Centauri</span> Globular cluster in the constellation Centaurus

Omega Centauri is a globular cluster in the constellation of Centaurus that was first identified as a non-stellar object by Edmond Halley in 1677. Located at a distance of 17,090 light-years, it is the largest-known globular cluster in the Milky Way at a diameter of roughly 150 light-years. It is estimated to contain approximately 10 million stars, and a total mass equivalent to 4 million solar masses, making it the most massive-known globular cluster in the Milky Way.

<span class="mw-page-title-main">Messier 84</span> Galaxy in the constellation Virgo

Messier 84 or M84, also known as NGC 4374, is a giant elliptical or lenticular galaxy in the constellation Virgo. Charles Messier discovered the object in 1781 in a systematic search for "nebulous objects" in the night sky. It is the 84th object in the Messier Catalogue and in the heavily populated core of the Virgo Cluster of galaxies, part of the local supercluster.

<span class="mw-page-title-main">Messier 91</span> Galaxy in the constellation Coma Berenices

Messier 91 is a barred spiral galaxy that is found in the south of Coma Berenices. It is in the local supercluster and is part of the Virgo Cluster of galaxies. It is about 63 million light-years away from our galaxy. It was the last of a group of eight "nebulae" – the term 'galaxy' only coming into use for these objects once it was realized in the 20th century that they were extragalactic – discovered by Charles Messier in 1781. It is the faintest object in the Messier catalog, with an apparent magnitude of 10.2.

The Herschel 400 catalogue is a subset of William Herschel's original Catalogue of Nebulae and Clusters of Stars, selected by Brenda F. Guzman (Branchett), Lydel Guzman, Paul Jones, James Morris, Peggy Taylor and Sara Saey of the Ancient City Astronomy Club in St. Augustine, Florida, United States c. 1980. They decided to generate the list after reading a letter published in Sky & Telescope by James Mullaney of Pittsburgh, Pennsylvania, USA.

<span class="mw-page-title-main">NGC 4874</span> Galaxy in the constellation Coma Berenices

NGC 4874 is a supergiant elliptical galaxy. It was discovered by the British astronomer Frederick William Herschel I in 1785, who catalogued it as a bright patch of nebulous feature. The second-brightest galaxy within the northern Coma Cluster, it is located at a distance of 109 megaparsecs from Earth.

<span class="mw-page-title-main">NGC 4473</span> Galaxy in the constellation Coma Berenices

NGC 4473 is an elliptical galaxy located about 50 million light-years away in the constellation of Coma Berenices. It was discovered by astronomer William Herschel on April 8, 1784. NGC 4473 has an inclination of about 71°. NGC 4473 is a member of a chain of galaxies called Markarian's Chain which is part of the larger Virgo Cluster of galaxies.

<span class="mw-page-title-main">NGC 4873</span> Galaxy in the constellation Coma Berenices

NGC 4873 is a lenticular galaxy located about 270 million light-years away in the constellation of Coma Berenices. NGC 4873 was discovered by astronomer Heinrich d'Arrest on May 10, 1863. The galaxy is a member of the Coma Cluster.

<span class="mw-page-title-main">NGC 4478</span> Galaxy in the constellation of Virgo

NGC 4478 is an elliptical galaxy located about 50 million light-years away in the constellation Virgo. NGC 4478 was discovered by astronomer William Herschel on April 12, 1784. NGC 4478 is a member of the Virgo Cluster.

<span class="mw-page-title-main">NGC 4871</span> Lenticular galaxy in the constellation Coma Berenices

NGC 4871 is a lenticular galaxy located about 310 million light-years away in the constellation of Coma Berenices. NGC 4871 was discovered by astronomer Heinrich d'Arrest on May 10, 1863. It is a member of the Coma Cluster.

<span class="mw-page-title-main">ESO 444-46</span> Galaxy in the constellation Centaurus

ESO 444-46 is a class E4 supergiant elliptical galaxy; the dominant and brightest member of the Abell 3558 galaxy cluster around 640 million light-years away in the constellation Centaurus. It lies within the core of the massive Shapley Supercluster, one of the closest neighboring superclusters. It is one of the largest galaxies in the local universe, and possibly contains one of the most massive black holes known. The black hole's mass is very uncertain, with estimates ranging from as low as 501 million M☉, to as high as 77.6 billion M☉.

<span class="mw-page-title-main">NGC 3309</span> Galaxy in the constellation Hydra

NGC 3309 is a giant elliptical galaxy located about 200 million light-years away in the constellation Hydra. NGC 3309 was discovered by astronomer John Herschel on March 24, 1835. The galaxy forms a pair with NGC 3311 which lies about 72,000 ly (22 kpc) away. Both galaxies dominate the center of the Hydra Cluster.

<span class="mw-page-title-main">NGC 3311</span> Galaxy in the constellation Hydra

NGC 3311 is a super-giant elliptical galaxy located about 190 million light-years away in the constellation Hydra. The galaxy was discovered by astronomer John Herschel on March 30, 1835. NGC 3311 is the brightest member of the Hydra Cluster and forms a pair with NGC 3309 which along with NGC 3311, dominate the central region of the Hydra Cluster.

<span class="mw-page-title-main">NeVe 1</span> Galaxy in the constellation Ophiuchus

NeVe 1 is a supergiant elliptical galaxy, which is the central, dominant member and brightest cluster galaxy (BCG) of the Ophiuchus Cluster. It lies at a distance of about 411 million light-years away from Earth and is located behind the Zone of Avoidance region in the sky. It is the host galaxy of the Ophiuchus Supercluster eruption, the most energetic astronomical event known.

References

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.