NGC 4253 | |
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![]() NGC 4253 by the Hubble Space Telescope | |
Observation data (J2000 epoch) | |
Constellation | Coma Berenices |
Right ascension | 12h 18m 26.5s [1] |
Declination | +29° 48′ 46″ [1] |
Redshift | 0.012882 ± 0.000050 [1] |
Heliocentric radial velocity | 3,862 ± 15 km/s [1] |
Distance | 185 Mly (56.6 Mpc) [1] |
Apparent magnitude (V) | 13.5 |
Characteristics | |
Type | (R')SB(s)a [1] |
Apparent size (V) | 1.0′ × 0.8′ [1] |
Notable features | Seyfert galaxy |
Other designations | |
UGC 7344, MRK 766, MCG +05-29-051, PGC 39525 [1] |
NGC 4253 is a barred spiral galaxy located in the constellation Coma Berenices. It is located at a distance of about 185 million light years from Earth, which, given its apparent dimensions, means that NGC 4253 is about 65,000 light years across. [1] It was discovered by William Herschel on February 3, 1788. [2] It is a Seyfert galaxy. [1]
The NGC 4253 is a barred galaxy with thick bar, while the arms form a ring. Marquez et al. suggested that the galaxy has a secondary bar perpendicular to the main bar, [3] although that could be an artifact due to the presence of strong dust lanes and no inner bar is visible in images by WFPC2 F606W of the Hubble Space Telescope. [4] There is evidence of star formation along the dust lanes in the leading egde of the bar, especially at the east half. [5]
The nucleus of NGC 4253 has been found to be active and it has been categorised as a narrow line type I Seyfert galaxy. [6] The most accepted theory for the energy source of active galactic nuclei is the presence of an accretion disk around a supermassive black hole. The mass of the black hole in the centre of NGC 5506 is estimated to be 1–13 × 106 M☉ based on reverberation mapping of the hydrogen lines, [7] 1.6+1.4
−1.2×106 M☉ based on time lag spectra, [8] and 1.26+1.00
−0.77×106 M☉ based on X-ray variations. [9]
The nucleus emits X-rays. The X-rays have been found to vary in intensity, exhibiting quasi-periodic oscillation, although this phenomenon appears to be transient. [10] The variability was found by ROSAT X-ray satellite. [11] The intensity varied by a factor of 3 every 6,450 seconds (about 1.8 hours) based on observations by XMM-Newton in 2005, [10] while in 2000 that period was estimated to be 4,200 seconds. [12] It has been suggested that the source of the oscillation lies at the inner part of the accretion disk. [10]
The galaxy has been found to host a maser and is a compact source in radiowaves. [13]
NGC 4253 belongs to a galaxy group known as LGG 276. Other members of this group includes the galaxies NGC 4131, NGC 4134, NGC 4169, NGC 4174, NGC 4175, NGC 4185, NGC 4196, NGC 4132, MCG 5-29-24, MCG 5-29-35, UGC 7221, and UGC 7294. [14] NGC 4245 lies at a projected distance of 16.5 arcminuntes. [15]
Seyfert galaxies are one of the two largest groups of active galaxies, along with quasars. They have quasar-like nuclei with very high surface brightnesses whose spectra reveal strong, high-ionisation emission lines, but unlike quasars, their host galaxies are clearly detectable.
NGC 3227 is an intermediate spiral galaxy that is interacting with the dwarf elliptical galaxy NGC 3226. The two galaxies are one of several examples of a spiral with a dwarf elliptical companion that are listed in the Atlas of Peculiar Galaxies. Both galaxies may be found in the constellation Leo. It is a member of the NGC 3227 Group of galaxies, which is a member of the Leo II Groups, a series of galaxies and galaxy clusters strung out from the right edge of the Virgo Supercluster.
NGC 5548 is a Type I Seyfert galaxy with a bright, active nucleus. This activity is caused by matter flowing onto a 65 million solar mass (M☉) supermassive black hole at the core. Morphologically, this is an unbarred lenticular galaxy with tightly-wound spiral arms, while shell and tidal tail features suggest that it has undergone a cosmologically-recent merger or interaction event. NGC 5548 is approximately 245 million light years away and appears in the constellation Boötes. The apparent visual magnitude of NGC 5548 is approximately 13.3 in the V band.
NGC 2992 is a Seyfert galaxy located 103 million light years distant in the equatorial constellation of Hydra. It was discovered in 1785 by Anglo-German astronomer William Herschel.
NGC 708 is an elliptical galaxy located 240 million light-years away in the constellation Andromeda and was discovered by astronomer William Herschel on September 21, 1786. It is classified as a cD galaxy and is the brightest member of Abell 262. NGC 708 is a weak FR I radio galaxy and is also classified as a type 2 Seyfert galaxy.
NGC 7469 is an intermediate spiral galaxy in the constellation of Pegasus. NGC 7469 is located about 200 million light-years away from Earth, which means, given its apparent dimensions, that NGC 7469 is approximately 90,000 light-years across. It was discovered by William Herschel on November 12, 1784.
NGC 536 is a barred spiral galaxy located in the constellation Andromeda. It is located at a distance of circa 200 million light-years from Earth, which, given its apparent dimensions, means that NGC 536 is about 180,000 light years across. It was discovered by William Herschel on September 13, 1784. It is a member of Hickson Compact Group 10, which also includes the galaxies NGC 529, NGC 531, and NGC 542. It belongs to the Perseus–Pisces Supercluster.
NGC 4939 is a spiral galaxy located in the constellation Virgo. It is located at a distance of about 120 million light years from Earth, which, given its apparent dimensions, means that NGC 4939 is about 190,000 light years across. It was discovered by William Herschel on March 25, 1786.
NGC 985 is a ring galaxy in the constellation of Cetus. It is located about 550 million light years away from Earth, which means, given its apparent dimensions, that NGC 985 is approximately 160,000 light years across. It was discovered by Francis Leavenworth in 1886. It is a type 1 Seyfert galaxy.
NGC 6951 is a barred spiral galaxy located in the constellation Cepheus. It is located at a distance of about 75 million light-years from Earth, which, given its apparent dimensions, means that NGC 6951 is about 100,000 light-years across. It was discovered by Jérôme Eugène Coggia in 1877 and independently by Lewis Swift in 1878.
NGC 4636 is an elliptical galaxy located in the constellation Virgo. It is a member of the NGC 4753 Group of galaxies, which 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 is located at a distance of about 55 million light years from Earth, which, given its apparent dimensions, means that NGC 4636 is about 105,000 light years across.
NGC 1386 is a spiral galaxy located in the constellation Eridanus. It is located at a distance of circa 53 million light years from Earth, which, given its apparent dimensions, means that NGC 1386 is about 50,000 light years across. It is a Seyfert galaxy, the only one in Fornax Cluster.
NGC 2273 is a barred spiral galaxy located in the constellation Lynx. It is located at a distance of circa 95 million light years from Earth, which, given its apparent dimensions, means that NGC 2273 is about 100,000 light years across. It was discovered by Nils Dunér on September 15, 1867.
NGC 5728 is an active barred spiral galaxy located 146 million light years away in the southern constellation of Libra. It was discovered on May 7, 1787 by William Herschel. The designation comes from the New General Catalogue of J. L. E. Dreyer, published in 1888. It has an apparent visual magnitude of 13.40 and spans an angle of 3.4 arcminutes. The galaxy shows a red shift of 0.00935 and has a heliocentric radial velocity of 2,803 km/s. It has an estimated mass of 72 billion times the mass of the Sun and stretches around 30 kpc across.
NGC 7679 is a lenticular galaxy with a peculiar morphology in the constellation Pisces. It is located at a distance of circa 200 million light years from Earth, which, given its apparent dimensions, means that NGC 7679 is about 60,000 light years across. It was discovered by Heinrich d'Arrest on September 23, 1864. The total infrared luminosity is 1011.05 L☉, and thus it is categorised as a luminous infrared galaxy. NGC 7679 is both a starburst galaxy and a Seyfert galaxy.
NGC 2617 is a Seyfert galaxy in the equatorial constellation of Hydra. It was discovered on February 12, 1885, by French astronomer Édouard Stephan. In 1888, Danish astronomer J. L. E. Dreyer described it as "extremely faint, very small, 2 very faint stars involved". It is located at an estimated distance of 202 million light years. In the infrared, the galaxy has an angular size of 0.693 by 0.652 arcminutes.
NGC 3516 is a barred lenticular galaxy in the constellation of Ursa Major. NGC 3516 is located about 150 million light years away from Earth, which means, given its apparent dimensions, that NGC 3516 is approximately 100,000 light years across. It was discovered by William Herschel on April 3, 1785.
Markarian 273 is a galaxy merger located in the constellation Ursa Major. It is located at a distance of about 500 million light years from Earth, which, given its apparent dimensions, means that Markarian 273 is about 130,000 light years across. It is an ultraluminous infrared galaxy and a Seyfert galaxy.
NGC 3786 is an intermediate spiral galaxy located 107.5 million light-years away in the northern constellation of Ursa Major. It was discovered by English astronomer John Herschel on April 10, 1831. This object appears to form a close pair with its peculiar neighbor to the north, NGC 3788. They show some indications of interaction, such as minor distortion of the disk or tidal features.
NGC 5273 is a lenticular galaxy located 54 million light-years away in the northern constellation of Canes Venatici. This galaxy was discovered by William Herschel on May 1, 1785. It is positioned 1+1⁄4° to the southeast of the star 25 Canum Venaticorum.