NGC 247 | |
---|---|
Observation data (J2000 epoch) | |
Constellation | Cetus |
Right ascension | 00h 47m 08.5s [1] |
Declination | −20° 45′ 37″ [1] |
Distance | 11.1 ± 1.2 Mly |
Apparent magnitude (V) | 9.9 [1] |
Characteristics | |
Type | SAB(s)d [1] |
Apparent size (V) | 21.4′ × 6.9′ [1] (70,000 light-years in diameter) |
Other designations | |
HIPASS J0047-20, LEDA 2758, ESO-LV 540-0220, IRAS F00446-2101, 2MASX J00470855-2045374, ESO 540-22, IRAS 00446-2101, MCG-04-03-005, GLXY G113.8-83.5+144, KUG 0044-210, UGCA 11, PGC 2758, [1] Caldwell 62 |
NGC 247 (also known as Caldwell 62 and commonly known as the Claw Galaxy [3] ) is an intermediate spiral galaxy (although it is sometimes classified as a dwarf spiral galaxy) about 11.1 Mly away in the constellation Cetus. This distance was confirmed in late February 2011. Previous measurements showed that the galaxy was about 12.2 Mly away, but this was proved to be wrong. [4] NGC 247 is a member of the Sculptor Group, and is 70 000 light years in diameter. [5]
NGC 247 has an unusually large void on one side of its spiral disk. This void contains some older, redder stars but no younger, bluer stars. [6]
NGC 247 is one of several galaxies that is gravitationally bound to the Sculptor Galaxy (NGC 253). These galaxies form a small core in the center of the Sculptor Group, which is one of the nearest groups of galaxies to the Milky Way. [7] Most other galaxies associated with the Sculptor Group are only weakly gravitationally bound to this core. [7] [8]
The Sculptor Group is a loose group of galaxies visible near the south galactic pole. The group is one of the closest groups of galaxies to the Local Group; the distance to the center of the group from the Milky Way is approximately 3.9 Mpc (12.7 Mly).
Messier 83 or M83, also known as the Southern Pinwheel Galaxy and NGC 5236, is a barred spiral galaxy approximately 15 million light-years away in the constellation borders of Hydra and Centaurus. Nicolas-Louis de Lacaille discovered M83 on 23 February 1752 at the Cape of Good Hope. Charles Messier added it to his catalogue of nebulous objects in March 1781.
NGC 55, is a Magellanic type barred spiral galaxy located about 6.5 million light-years away in the constellation Sculptor. Along with its neighbor NGC 300, it is one of the closest galaxies to the Local Group, probably lying between the Milky Way and the Sculptor Group. It has an estimated mass of (2.0 ± 0.4) × 1010M☉.
NGC 404 is a field galaxy located about 10 million light years away in the constellation Andromeda. It was discovered by William Herschel in 1784, and is visible through small telescopes. NGC 404 lies just beyond the Local Group and does not appear gravitationally bound to it. It is located within 7 arc-minutes of second magnitude star Mirach, making it a difficult target to observe or photograph and granting it the nickname "Mirach's Ghost".
Messier 95, also known as M95 or NGC 3351, is a barred spiral galaxy about 33 million light-years away in the zodiac constellation Leo. It was discovered by Pierre Méchain in 1781, and catalogued by compatriot Charles Messier four days later. In 2012 its most recent supernova was discovered.
The Centaurus A/M83 Group is a complex group of galaxies in the constellations Hydra, Centaurus, and Virgo. The group may be roughly divided into two subgroups. The Cen A Subgroup, at a distance of 11.9 Mly, is centered on Centaurus A, a nearby radio galaxy. The M83 Subgroup, at a distance of 14.9 Mly, is centered on the Messier 83 (M83), a face-on spiral galaxy.
Messier 96 is an intermediate spiral galaxy about 31 million light-years away in the constellation Leo.
The Sculptor Galaxy is an intermediate spiral galaxy in the constellation Sculptor. The Sculptor Galaxy is a starburst galaxy, which means that it is currently undergoing a period of intense star formation.
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 7793 is a flocculent spiral galaxy in the southern constellation of Sculptor. It was discovered in 1826 by Scottish astronomer James Dunlop. The galaxy is located at a distance of 12.2 million light years and is receding with a heliocentric radial velocity of 227 km/s. NGC 7793 is one of the five brightest galaxies within the Sculptor Group.
NGC 4945 (also known as Caldwell 83) is a barred spiral galaxy in the constellation Centaurus, visible near the star Xi Centauri. The galaxy was discovered by James Dunlop in 1826 and is thought to be similar to the Milky Way Galaxy, although X-ray observations show that NGC 4945 has an unusual energetic Seyfert 2 nucleus that might house a supermassive black hole. Around the nucleus of the galaxy, there is a dense disk of dust and gas, along with many dense star clusters. This object has an estimated mass of 1.4+1.4
−0.7×1011 M☉.
The M94 Group is a loose, extended group of galaxies located about 13 million light-years away in the constellations Canes Venatici and Coma Berenices. The group is one of many groups that lies within the Virgo Supercluster and one of the closest groups to the Local Group.
A field galaxy is a galaxy that does not belong to a larger galaxy group or cluster and hence is gravitationally alone.
NGC 4236 is a barred spiral galaxy located in the constellation Draco.
NGC 45 is a low surface brightness spiral galaxy in the equatorial constellation of Cetus. It was discovered on 11 November 1835 by the English astronomer John Herschel. The galaxy is located at a distance of 22 million light years and is receding with a heliocentric radial velocity of 466 km/s. It is located in the vicinity of the Sculptor Group, but is most likely a background galaxy.
NGC 908 is an unbarred spiral galaxy in the constellation Cetus. It was discovered in 1786 by William Herschel. This galaxy is 56 million light years away from Earth. It is the main galaxy in the NGC 908 group, which also includes NGC 899, NGC 907, and IC 223.
NGC 5643 is an intermediate spiral galaxy in the constellation Lupus. Based on the tip of the red-giant branch distance indicator, it is located at a distance of about 40 million light-years. NGC 5643 has an active galactic nucleus and is a type II Seyfert galaxy.
NGC 2336 is a Barred spiral galaxy located in the constellation Camelopardalis. It is located at a distance of circa 100 million light years from Earth, which, given its apparent dimensions, means that NGC 2336 is about 200,000 light years across. It was discovered by Wilhelm Tempel in 1876.
NGC 5965 is a spiral galaxy located in the constellation Draco. It is located at a distance of circa 150 million light years from Earth, which, given its apparent dimensions, means that NGC 5965 is about 260,000 light years across. It was discovered by William Herschel on May 5, 1788.
NGC 6907 is a spiral galaxy located in the constellation Capricornus. It is located at a distance of about 120 million light years from Earth, which, given its apparent dimensions, means that NGC 6907 is about 115,000 light years across. It was discovered by William Herschel on July 12, 1784. The total infrared luminosity of the galaxy is 1011.03 L☉, and thus it is categorised as a luminous infrared galaxy.