HCG 87 | |
---|---|
Observation data (Epoch ) | |
Constellation(s) | Capricornus |
Right ascension | 20h 48m 11.9ss [1] |
Declination | −19° 50′ 35″ [1] |
Number of galaxies | ~5 |
Distance | 400 million |
Other designations | |
None | |
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 |
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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.
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