NGC 1218 | |
---|---|
Observation data (J2000.0 epoch) | |
Constellation | Cetus |
Right ascension | 03h 08m 26.2s [1] |
Declination | +04° 06′ 39.3″ [1] |
Redshift | 0.0288 [2] |
Heliocentric radial velocity | 8,485±15 km/s [3] |
Galactocentric velocity | 8,488±15 km/s [3] |
Distance | 378,600,000 ly (116.08 Mpc) [1] |
Group or cluster | [CHM 2007] LDC 223 [1] |
Apparent magnitude (V) | 8.460 [3] |
Apparent magnitude (B) | 12.84 [4] |
Absolute magnitude (V) | -2.70 [3] |
Surface brightness | 1.19×10−1 [3] |
Characteristics | |
Type | S0/a [3] |
Size | 225,400 ly (69.11 kpc) (diameter) [3] |
Apparent size (V) | 1.147′ × 0.917′ [1] |
Other designations | |
Gaia DR1 2673462523030912, 2MASS J03082623+0406390, 2MASX J03082624+0406388, UGC 2555, LEDA 11749, MCG +01-09-001, PGC 011749, CGCG 0305.8+0355 [1] [3] [Note 2] |
NGC 1218 is a lenticular galaxy in Cetus that hosts the radio source 3C 78. It was discovered in 1886 by American astronomer Lewis A. Swift. It is located at l = 174.86, b = -44.51 in the galactic coordinate system. [1]
Discovered by Lewis Swift on September 6, 1886, [5] NGC 1218 was one of the original objects included in the New General Catalogue. [6] 3C 78 was discovered c. 1957, and subsequently included in the Third Cambridge Catalogue of Radio Sources (3C). [7]
In 1982, it was found that the nucleus of NGC 1218 emits a radio jet. [8] A follow-up study in 1986 corroborated the presence of the jet, as well as finding evidence of a possible weak counter-jet. [9] The Hubble Space Telescope observed NGC 1218 on August 17, 1994. An optical jet of synchrotron radiation similar to that of Messier 87 was subsequently found. [10]
On September 6, 2000, a type Ia supernova was detected in NGC 1218. A 2002 study found that the previously identified radio jet was the cause. [11]
In 2023, the proper motion of 3C 78 was determined using observations from the Very Large Array (VLA), as well as a single observation from the Atacama Large Millimeter/submillimeter Array (ALMA). [12]
NGC 1218 is a lenticular (S/0a) radio galaxy, with a radio halo roughly equivalent in size to the optical halo's extent. [8] The observable synchrotron jet has a total length of 1.37 arcseconds (0.75 kpc), and expands substantially at 0.5 arcseconds from the nucleus. [10]
NGC 1218 has an approximate hydrogen mass of <36×109 M☉. [9]
3C 78 is an astronomical radio source with an angular extent of approximately 80 × 55 arcseconds squared. [9] According to Tabara and Inoue (1980), 3C 78 has a rotation measure of 8.7 ± 1.9 m−2 and an intrinsic position angle of 87° ± 4°, although Simard-Normandin, Kronberg, and Button (1981) claim that it has a rotation measure of 14 ± 2 m−2 and an intrinsic position angle of 85° ± 3°. [13] [14]
It possesses a radio jet approximately one arcsecond (0.58 kpc) in length, with three bright, compact inhomogeneities (or "knots"), with the second and thirds ones being the most prominent. The second knot has a longitudinal motion of approximately 0.51 ± 0.14c at roughly 200 pc, and the third knot had an apparent superluminal backwards motion of −2.6 ± 2c prior to 2000, followed by a forward motion of 0.5 ± 2c, both at roughly 300 pc. [12]
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.
Messier 108 is a barred spiral galaxy about 46 million light-years away from Earth in the northern constellation Ursa Major. It was discovered by Pierre Méchain in 1781 or 1782. From the Earth, this galaxy is seen almost edge-on.
IC 1101 is a class S0 supergiant (cD) lenticular galaxy at the center of the Abell 2029 galaxy cluster. It has an isophotal diameter at about 123.65 to 169.61 kiloparsecs. It possesses a diffuse core which is the largest known core of any galaxy to date, and contains a supermassive black hole, one of the largest discovered. IC 1101 is located at 354.0 megaparsecs from Earth. It was discovered on 19 June 1790, by the British astronomer William Herschel.
NGC 4710 is an edge-on lenticular galaxy in the northern constellation of Coma Berenices. It was discovered on March 21, 1784 by German-British astronomer William Herschel. This galaxy has a B-band visual magnitude of 11.60 and an angular size of 3.0′ × 0.8′. It is located at a distance of 54.5 ± 3.6 million light-years (16.7 ± 1.1 Mpc) from the Milky Way, and is receding with a heliocentric radial velocity of 1,129 km/s. This is a member of the Virgo Cluster, with a projected offset of ~6° from the cluster center and a cluster crossing time of around two billion years.
3C 305, also known as IC 1065, is a lenticular galaxy located in the constellation Draco. The galaxy is located 577 million light-years away from Earth. It has an active galactic nucleus and is classified as a Seyfert 2 galaxy. This galaxy was discovered by American astronomer Lewis Swift on April 7th, 1888.
NGC 5929 is a well-studied Seyfert galaxy in the constellation Boötes. It was discovered by English astronomer John Herschel on May 13, 1828. In the revised New General Catalogue it is described as "elongated, brighter toward the middle, with a slightly diffuse halo". This galaxy is located at an estimated distance of 133 million light-years. It forms an interacting pair with NGC 5930 at an angular separation of 0.5′; together they form entry number 90 in Halton Arp's 1966 Atlas of Peculiar Galaxies. A dust streak from NGC 5930 appears to lie in front of NGC 5929, suggesting that the former galaxy is the closer member of this pair.
Hercules A is a bright astronomical radio source in the constellation Hercules corresponding to the galaxy 3C 348.
NGC 3862 is an elliptical galaxy located 300 million light-years away in the constellation Leo. Discovered by astronomer William Herschel on April 27, 1785, NGC 3862 is an outlying member of the Leo Cluster.
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 5982 is an elliptical galaxy located in the constellation Draco. It is located at a distance of circa 130 million light years from Earth, which, given its apparent dimensions, means that NGC 5982 is about 100,000 light years across. It was discovered by William Herschel on May 25, 1788.
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 3665 is a lenticular galaxy located in the constellation Ursa Major. It is located at a distance of circa 85 million light-years from Earth, which, given its apparent dimensions, means that NGC 3665 is about 85,000 light years across. It was discovered by William Herschel on March 23, 1789.
NGC 5363 is a lenticular galaxy located in the constellation Virgo. It is located at a distance of circa 65 million light years from Earth, which, given its apparent dimensions, means that NGC 5363 is about 100,000 light years across. It was discovered by William Herschel on January 19, 1784. It is a member of the NGC 5364 Group of galaxies, itself one of the Virgo III Groups strung out to the east of the Virgo Supercluster of galaxies.
NGC 4324 is a lenticular galaxy located about 85 million light-years away in the constellation Virgo. It was discovered by astronomer Heinrich d'Arrest on March 4, 1862. NGC 4324 has a stellar mass of 5.62 × 1010M☉, and a baryonic mass of 5.88 × 1010M☉. The galaxy's total mass is around 5.25 × 1011M☉. NGC 4324 is notable for having a ring of star formation surrounding its nucleus. It was considered a member of the Virgo II Groups until 1999, when its distance was recalculated and it was placed in the Virgo W Group.
ESO 383-76 is an elongated, X-ray luminous supergiant elliptical galaxy, residing as the dominant, brightest cluster galaxy (BCG) of the Abell 3571 galaxy cluster, the sixth-brightest in the sky at X-ray wavelengths. It is located at the distance of 200.6 megaparsecs from Earth, and is possibly a member of the large Shapley Supercluster. With a diameter of about 540.9 kiloparsecs, it is one of the largest galaxies known. It also contains a supermassive black hole, one of the most massive known with mass estimates varying from 2 billion M☉ to 28 billion M☉.
NGC 2110 is a lenticular galaxy located in the constellation Orion. It is located at a distance of about 120 million light years from Earth, which, given its apparent dimensions, means that NGC 2110 is about 90,000 light years across. It was discovered by William Herschel on October 5, 1785. It is a Seyfert galaxy.
NGC 5953 is a peculiar spiral galaxy in the constellation Serpens. The galaxy lies about 80 million light years away from Earth, which means, given its apparent dimensions, that NGC 5953 is approximately 35,000 light years across. It was discovered by William Herschel on April 17, 1784. NGC 5953 interacts with NGC 5954 forming a pair known as Arp 91.
An extended emission-line region (EELR) is a giant interstellar cloud ionized by the radiation of an active galactic nucleus (AGN) inside a galaxy or photons produced by the shocks associated with the radio jets. An EELR can appear as a resolved cloud in relative nearby galaxies and as narrow emission lines in more distant galaxies.
NGC 2484 is a large lenticular galaxy located in the Lynx constellation. It is situated 560 million light-years away from the Milky Way, which given by its apparent dimensions, means NGC 2484 is around 304,000 light-years across. It is classified a Fanaroff and Riley radio galaxy.
3C 309.1 is a quasar located in the constellation of Ursa Minor. It has a redshift (z) of 0.90 and was first identified as an astronomical radio source from the Third Cambridge Catalogue of Radio Sources by in 1966. This object contains a compact steep spectrum (CSS) source, and is classified as one of the brightest and largest of its kind.