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.
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.
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.
NGC 4203 is the New General Catalogue identifier for a lenticular galaxy in the northern constellation of Coma Berenices. It was discovered on March 20, 1787 by English astronomer William Herschel, and is situated 5.5° to the northwest of the 4th magnitude star Gamma Comae Berenices and can be viewed with a small telescope. The morphological classification of NGC 4203 is SAB0−, indicating that it has a lenticular form with tightly wound spiral arms and a weak bar structure at the nucleus.
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 541 is a lenticular galaxy located in the constellation Cetus. It is located at a distance of about 230 million light years from Earth, which, given its apparent dimensions, means that NGC 541 is about 130,000 light years across. It was discovered by Heinrich d'Arrest on October 30, 1864. It is a member of the Abell 194 galaxy cluster and is included in the Atlas of Peculiar Galaxies in the category galaxies with nearby fragments. NGC 541 is a radio galaxy of Fanaroff–Riley class I, also known as 3C 40A.
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 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 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 545 is a lenticular galaxy located in the constellation Cetus. It is located at a distance of about 250 million light years from Earth, which, given its apparent dimensions, means that NGC 545 is about 180,000 light years across. It was discovered by William Herschel on October 1, 1785. It is a member of the Abell 194 galaxy cluster and is included along with NGC 547 in the Atlas of Peculiar Galaxies.
NGC 4513 is a lenticular galaxy and a ring galaxy located about 110 million light-years away in the constellation Draco. It was discovered by astronomer Heinrich d'Arrest on October 16, 1866.
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.
NGC 5252 is a lenticular galaxy located in the constellation Virgo. It is located at a distance of about 220 to 320 million light years from Earth, which, given its apparent dimensions, means that NGC 5252 is about 100,000 light years across. It was discovered by William Herschel on February 2, 1786.
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 7720 is an elliptical galaxy located in the constellation Pegasus. It is located at a distance of about 380 million light years from Earth, which, given its apparent dimensions, means that NGC 7720 is about 180,000 light years across. NGC 7720 is the main galaxy of Abell 2634 galaxy cluster and is a radio galaxy. It was discovered by William Herschel on September 10, 1784.
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 thousand light-years across. It is classified a Fanaroff and Riley radio galaxy.