HCG 87 | |
---|---|
Observation data (Epoch ) | |
Constellation(s) | Capricornus |
Right ascension | 20h 48m 11.9ss [1] |
Declination | −19° 50′ 35″ [1] |
Number of galaxies | ~5 |
Redshift | 8874 km/s [1] |
Distance | 400 million |
HCG 87 is a compact group of galaxies listed in the Hickson Compact Group Catalogue. This group is about 400 million light-years away [2] in the constellation Capricornus. The group distinguishes itself as one of the most compact groups of galaxies, hosting two active galactic nuclei and a starburst among its three members, all of which show signs of interaction. [3] This interaction, which astronomers have called visually, and scientifically, intriguing [4] is being examined to understand the influence of active nuclei on star formation histories.
Name | Type [5] | R.A. (J2000) [5] | Dec. (J2000) [5] | Redshift (km/s) [5] | Apparent Magnitude [5] |
---|---|---|---|---|---|
HCG 87a | S0 pec | 20h 48m 15.0s | −19° 50′ 58″ | 8443 ± 14 | 15.3 |
HCG 87b | SA(r)0 pec | 20h 48m 10.9s | −19° 51′ 23″ | 8740 ± 20 | 15.4 |
HCG 87c | Sb | 20h 48m 12.0s | −19° 49′ 56″ | 8914 ± 7 | 16.1 |
HCG 87d | Sd | 20h 48m 12.8s | −19° 50′ 46″ | 10200 ± 160 | 17.8 |
Seyfert's Sextet is a group of galaxies about 190 million light-years away in the constellation Serpens. The group appears to contain six members, but one of the galaxies, NGC 6027d, is a background object and another "galaxy," NGC 6027e, is actually a part of the tail from galaxy NGC 6027. The gravitational interaction among these galaxies should continue for hundreds of millions of years. Ultimately, the galaxies will merge to form a single giant elliptical galaxy.
Stephan's Quintet is a visual grouping of five galaxies of which four form the first compact galaxy group ever discovered. The group, visible in the constellation Pegasus, was discovered by Édouard Stephan in 1877 at the Marseille Observatory. The group is the most studied of all the compact galaxy groups. The brightest member of the visual grouping is NGC 7320, which has extensive H II regions, identified as red blobs, where active star formation is occurring.
Messier 60 or M60, also known as NGC 4649, is an elliptical galaxy approximately 57 million light-years away in the equatorial constellation of Virgo. Together with NGC 4647, it forms a pair known as Arp 116. Messier 60 and nearby elliptical galaxy Messier 59 were discovered by Johann Gottfried Koehler in April 1779, observing a comet in the same part of the sky. Charles Messier added both to his catalogue about three days after this.
NGC 1275 is a type 1.5 Seyfert galaxy located around 237 million light-years away in the direction of the constellation Perseus. NGC 1275 is a member of the large Perseus Cluster of galaxies.
NGC 1512 is a barred spiral galaxy approximately 38 million light-years away from Earth in the constellation Horologium. The galaxy displays a double ring structure, with a (nuclear) ring around the galactic nucleus and an (inner) further out in the main disk. The galaxy hosts an extended UV disc with at least 200 clusters with recent star formation activity. NGC 1512 is a member of the Dorado Group.
NGC 520 is a pair of colliding spiral galaxies about 105 million light-years away in the constellation Pisces. They were discovered by astronomer William Herschel on 13 December 1784.
NGC 5005, also known as Caldwell 29, is an inclined spiral galaxy in the constellation Canes Venatici. The galaxy has a relatively bright nucleus and a bright disk that contains multiple dust lanes. The galaxy's high surface brightness makes it an object that is visible to amateur astronomers using large amateur telescopes.
A Hickson Compact Group is a collection of galaxies designated as published by Paul Hickson in 1982.
NGC 4261 is an elliptical galaxy located around 100 million light-years away in the constellation Virgo. It was discovered April 13, 1784, by the German-born astronomer William Herschel. The galaxy is a member of its own somewhat meager galaxy group known as the NGC 4261 group, which is part of the Virgo Cluster.
Arp 273 is a pair of interacting galaxies, 300 million light years away in the constellation Andromeda. It was first described in the Atlas of Peculiar Galaxies, compiled by Halton Arp in 1966. The larger of the spiral galaxies, known as UGC 1810, is about five times more massive than the smaller galaxy. It has a disc that is tidally distorted into a rose-like shape by the gravitational pull of the companion galaxy below it, known as UGC 1813. The smaller galaxy shows distinct signs of active star formation at its nucleus, and "it is thought that the smaller galaxy has actually passed through the larger one."
NGC 3718, also called Arp 214, is a galaxy located approximately 52 million light years from Earth in the constellation Ursa Major. It is either a lenticular or spiral galaxy.
NGC 1741 is a distant pair of interacting galaxies in the Eridanus constellation. It was discovered on 6 January 1878 by French astronomer Édouard Stephan. As a result of the collision, the galaxies are in a rapid starburst phase. The galaxies are classed as Wolf–Rayet galaxies due to their high content of rare Wolf–Rayet stars.
NGC 1190 is a lenticular galaxy approximately 109 million light-years away from Earth in the constellation of Eridanus. It was discovered by American astronomer Francis Leavenworth on December 2, 1885 with the 26" refractor at Leander McCormick Observatory.
NGC 1189 is a barred spiral galaxy approximately 105 million light-years away from Earth in the constellation of Eridanus. It was discovered by American astronomer Francis Leavenworth on December 2, 1885 with the 26" refractor at Leander McCormick Observatory.
NGC 1191 is a lenticular galaxy approximately 406 million light-years away from Earth in the constellation of Eridanus. It was discovered by American astronomer Francis Leavenworth on December 2, 1885 with the 26" refractor at Leander McCormick Observatory.
NGC 1199 is an elliptical galaxy approximately 107 million light-years away from Earth in the constellation of Eridanus. It was discovered by William Herschel on December 30, 1785.
NGC 1192 is a lenticular galaxy approximately 417 million light-years away from Earth in the constellation of Eridanus. It was discovered by American astronomer Francis Leavenworth on December 2, 1885 with the 26" refractor at Leander McCormick Observatory.
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 5910 is an elliptical galaxy located about 540 million light-years away in the constellation Serpens. It was discovered by astronomer William Hershel on April 13, 1785. NGC 5910 is also a strong radio source with a conspicuous nuclear jet.
NGC 7609 or known as Arp 150 and HCG 95A, is a large elliptical galaxy located in Pegasus. Its speed relative to the cosmic microwave background is 11,879 km/s, which corresponds the galaxy to be located 554 million light-years away from Earth. NGC 7609 was discovered on October 5, 1864, by Albert Marth and included in Halton Arp's, Atlas of Peculiar Galaxies in galaxies that produces jets.
PS File download need Photoshop or GIMP