NGC 5668 | |
---|---|
Observation data (J2000 epoch) | |
Constellation | Virgo |
Right ascension | 14h 33m 24.331s [1] |
Declination | +04° 27′ 01.75″ [1] |
Helio radial velocity | 1,582 ± 5 [2] km/s |
Distance | 80.9 ± 5.5 million light years (24.8 ± 1.7 Mpc) [2] |
Characteristics | |
Type | SA(s)d [2] |
Mass | 5.7×1010 [2] M☉ |
Other designations | |
UGC 9363 [3] |
NGC 5668 is a nearly face-on spiral galaxy, visual magnitude about 11.5, [4] located about 81 [2] million light years away in the constellation Virgo. It was discovered in 1786 by William Herschel. [4] It is a member of the NGC 5638 Group of galaxies, itself one of the Virgo III Groups strung out to the east of the Virgo Supercluster of galaxies. [5]
As seen from the Earth, it is inclined by an angle of 18° to the line of sight along a position angle of 145°. The morphological classification in the De Vaucouleurs system is SA(s)d, [2] indicating a pure spiral structure with loosely wound arms. [6] However, optical images of the galaxy indicate the presence of a weak bar structure spanning an angle of 12″ across the nucleus. There is a dwarf galaxy located around 650×10 3 ly (200 kpc) to the southeast of NGC 5668, and the two may be gravitationally interacting. [2]
Three supernovae have been observed in this galaxy: SN 1952G, SN 1954B, and SN 2004G. [7] The last, a type II supernova, [8] was initially imaged on January 19, 2004, at 43" to the west and 12".5 south of the galaxy core. [7] High velocity clouds of neutral hydrogen have been observed in NGC 5668, which may have their origin in supernova explosions and strong stellar winds. [9]
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.
Messier 99 or M99, also known as NGC 4254, is a grand design spiral galaxy in the northern constellation Coma Berenices approximately 15,000,000 parsecs from the Milky Way. It was discovered by Pierre Méchain on 17 March 1781. The discovery was then reported to Charles Messier, who included the object in the Messier Catalogue of comet-like objects. It was one of the first galaxies in which a spiral pattern was seen. This pattern was first identified by Lord Rosse in the spring of 1846.
NGC 4725 is an intermediate barred spiral galaxy with a prominent ring structure, located in the northern constellation of Coma Berenices near the north galactic pole. It was discovered by German-born astronomer William Herschel on April 6, 1785. The galaxy lies at a distance of approximately 40 megalight-years from the Milky Way.
NGC 2997 is a face-on unbarred spiral galaxy about 40 million light-years away in the faint southern constellation of Antlia. It was discovered March 4, 1793 by German-born astronomer William Herschel. J. L. E. Dreyer described it as, "a remarkable object, very faint, very large, very gradually then very suddenly bright middle and 4 arcsec nucleus. This is the brightest galaxy of the NGC 2997 group of galaxies, and was featured on the cover of the first edition of Galactic Dynamics by James Binney and Scott Tremaine.
NGC 4639 is a barred spiral galaxy located in the equatorial constellation of Virgo. It was discovered by German-born astronomer William Herschel on April 12, 1784. John L. E. Dreyer described it as "pretty bright, small, extended, mottled but not resolved, 12th magnitude star 1 arcmin to southeast". This is a relatively nearby galaxy, lying approximately 72 million light-years away from the Milky Way. It is a companion to NGC 4654, and the two appear to have interacted roughly 500 million years ago. NGC 4639 is a member of the Virgo Cluster.
NGC 7537 is a spiral galaxy located in the equatorial constellation of Pisces, about 1.5° to the NNW of Gamma Piscium. It was first documented by German-born astronomer William Herschel on Aug 30, 1785. J. L. E. Dreyer described it as, "very faint, considerably small, round, brighter middle, southwestern of 2". This galaxy lies at a distance of approximately 127 Mly (39 Mpc) from the Milky Way, and is a member of the Pegasus I cluster.
NGC 2775, also known as Caldwell 48, is a spiral galaxy in the constellation Cancer. It is 67 million light-years away from the Milky Way. It was discovered by William Herschel in 1783. NGC 2775 belongs to the Antlia-Hydra Cluster of galaxies and is the most prominent member of the NGC 2775 Group, a small galaxy group in the Virgo Supercluster, along with the Local Group. Other members of the NGC 2775 Group include NGC 2777 and UGC 4781.
NGC 4666 is a spiral galaxy in the equatorial constellation of Virgo, located at a distance of approximately 55 megalight-years from the Milky Way. It was discovered by the German-born astronomer William Herschel on February 22, 1784. 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. John L. E. Dreyer described it as "bright, very large, much extended 45°±, pretty suddenly brighter middle". It is a member of an interacting system with NGC 4668 and a dwarf galaxy, and belongs to a small group that also includes NGC 4632.
NGC 5584 is a barred spiral galaxy in the constellation Virgo. It was discovered July 27, 1881 by American astronomer E. E. Barnard. Distance determination using Cepheid variable measurements gives an estimate of 75 million light years, whereas the tip of the red-giant branch approach yields a distance of 73.4 million light years. It is receding with a heliocentric radial velocity of 1,637 km/s. It is a member of the Virgo III Groups, a series of galaxies and galaxy clusters strung out to the east of the Virgo Supercluster of galaxies.
NGC 634 is a spiral galaxy, lying at a distance of 217.1 megalight-years away from the Milky Way in the northern constellation of Triangulum. This object was discovered in the nineteenth century by French astronomer Édouard Stephan. It is inclined by an angle of 82.4° to the line of sight from the Earth, and thus is being viewed nearly edge on.
NGC 2748 is a spiral galaxy in the northern circumpolar constellation of Camelopardalis, located at a distance of 61.3 megalight-years from the Milky Way. It was discovered September 2, 1828 by John Herschel. The morphological classification of SAbc indicates this is an unbarred spiral with moderate to loosely-wound spiral arms. It is a disk-like peculiar galaxy with a stellar shell that is rotating about the main galactic axis. This shell was most likely formed through the capture and disruption of a dwarf companion. The galactic nucleus likely contains a supermassive black hole with a mass of 4.4+3.5
−3.6×107 M☉, or 44 million times the mass of the Sun.
NGC 4451 is a spiral galaxy in the equatorial Virgo constellation. It was discovered at the Copenhagen Observatory on March 19, 1865 by Heinrich d'Arrest, who used an 11" refractor telescope. The galaxy is located at a distance of 85 million light years and is receding with a heliocentric radial velocity of 862 km/s. It is a member of the Virgo cluster of galaxies.
NGC 3021 is a spiral galaxy in the northern constellation of Leo Minor. It is about 93 million light-years away from Earth, and is receding with a heliocentric radial velocity of 1,537±4 km/s. This galaxy was discovered December 7, 1785 by Anglo-German astronomer William Herschel. The morphological classification of NGC 3021 is SA(rs)bc, which indicates a spiral galaxy with no central bar (SA), an incomplete inner ring structure (rs), and moderate to loosely wound spiral arms (bc).
NGC 124 is a spiral galaxy in the constellation Cetus. It was discovered by Truman Henry Safford on September 23, 1867. The galaxy was described as "very faint, large, diffuse, 2 faint stars to northwest" by John Louis Emil Dreyer, the compiler of the New General Catalogue.
NGC 4388 is an active spiral galaxy in the equatorial constellation of Virgo. It was discovered April 17, 1784 by Wilhelm Herschel. This galaxy is located at a distance of 57 million light years and is receding with a radial velocity of 2,524 km/s. It is one of the brightest galaxies of the Virgo Cluster due to its luminous nucleus. NGC 4388 is located 1.3° to the west of the cluster center, which translates to a projected distance of ≈400 kpc.
NGC 6753 is a massive unbarred spiral galaxy, seen almost exactly face-on, in the southern constellation of Pavo. It was discovered by the English astronomer John Herschel on July 5, 1836. The galaxy is located at a distance of 142 million light years from the Milky Way, and is receding with a heliocentric radial velocity of 3,140 km/s. It does not display any indications of a recent interaction with another galaxy or cluster.
NGC 4302 is an edge-on spiral galaxy located about 55 million light-years away in the constellation Coma Berenices. It was discovered by astronomer William Herschel on April 8, 1784 and is a member of the Virgo Cluster.
NGC 3294 is a spiral galaxy in the constellation Leo Minor. It was discovered by William Herschel on Mar 17, 1787. It 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. The galaxy is located at a distance of 98 million light years and is receding with a heliocentric radial velocity of 1,586 km/s. The morphological class of NGC 3294 is SA(rs)bc, which means this is a spiral galaxy with no central bar (SA), an incomplete inner ring structure (rs), and moderately wound spiral arms (bc).
NGC 1325 is a flocculent spiral galaxy situated in the constellation of Eridanus. Located about 75 million light years away, it is a member of the Eridanus cluster of galaxies, a cluster of about 200 galaxies. It was discovered by William Herschel on 19 December 1799.
NGC 3044 is a barred spiral galaxy in the equatorial constellation of Sextans. It was discovered on December 13, 1784, by German-born English astronomer William Herschel. In 1888, Danish astronomer J. L. E. Dreyer described it as "very faint, very large, very much extended 122°". It is located at an estimated distance of 67 million light years. In the B band of the UBV photometric system, the galaxy spans 4.70′ by 0.80′ with the major axis aligned along a position angle of 113°. It is a relatively isolated galaxy with no nearby companions. R. B. Tully in 1988 assigned it as a member of the widely displaced Leo Cloud.