# Hickson Compact Group

A Hickson Compact Group (abbreviation: HCG) is a collection of galaxies designated as published by Paul Hickson in 1982.
The most famous group on Hickson's list of 100 objects is HCG 92, Stephan's Quintet.

## Hickson Compact Groups

According to Hickson: “Most compact groups contain a high fraction of galaxies having morphological or kinematical peculiarities, nuclear radio and infrared emission, and starburst or active galactic nuclei (AGN) activity. They contain large quantities of diffuse gas and are dynamically dominated by dark matter. They most likely form as subsystems within looser associations and evolve by gravitational processes. Strong galaxy interactions result and merging is expected to lead to the ultimate demise of the group. Compact groups are surprisingly numerous, and may play a significant role in galaxy evolution.”

## List

| HCG | Right ascension | Declination | Galaxy count | Members | Notes |
| 1 | 00$^h$ 26.0$^m$ | +25° 43′ | 4 | UGC 248, PGC 1625, PGC 1614, PGC 1618 | |
| 2 | 00$^h$ 31$^m$ 24$^s$ | +08° 26.8′ | 4 | UGC 312, Markarian 552, UGC 314, UGC 315 | |
| 3 | 00$^h$ 34$^m$ 11$^s$ | −07° 35.6′ | 4 | MCG-01-02-032, PGC 2064, PGC 2059, PGC 2043 | |
| 4 | 00$^h$ 34$^m$ 15.3$^s$ | −21° 26′ 52″ | 5 | ESO 540-1, ESO 540-2, PGC 2051, PGC 2057, PGC 2040 | |
| 5 | 00$^h$ 38$^m$ 54$^s$ | +07° 03.8′ | 4 | NGC 190, NGC 190S, MCG+01-02-042, PGC 2326 | |
| 6 | 00$^h$ 39$^m$ 10$^s$ | −08° 23.7′ | 4 | PGC 2347, PGC 2350, PGC 2351, PGC 2353 | |
| 7 | 00$^h$ 39$^m$ 15.9$^s$ | +00° 53′ 17″ | 4 | NGC 192, NGC 196, NGC 197, NGC 201 | Contains three spirals and one lenticular galaxy |
| 8 | 00$^h$ 49$^m$ 37$^s$ | +23° 34.8′ | 4 | MCG+04-03-008, PGC 2888, PGC 2890, PGC 2892 | |
| 9 | 00$^h$ 54$^m$ 18$^s$ | −23° 33.1′ | 4 | MCG-04-03-027, MCG-04-03-028, PGC 3196, PGC 3200 | |
| 10 | 01$^h$ 26$^m$ 24.5$^s$ | +34° 42′ 51″ | 4 | NGC 536, NGC 529, NGC 531, NGC 542 | |
| 11 | 01$^h$ 26.6$^m$ | −23° 13′ | 4 | ESO 476-8, MCG-04-04-010, PGC 5357, PGC 5381 | |
| 12 | 01$^h$ 27$^m$ 33.7$^s$ | −04° 40′ 14″ | 5 | MCG-01-04-052, PGC 5432, PGC 5439, PGC 5443, PGC 5445 | |
| 13 | 01$^h$ 32.4$^m$ | −07° 52′ | 5 | MCG-01-05-002, MCG-01-05-003, MCG-01-05-004, PGC 5728, PGC 5741 | |
| 14 | 01$^h$ 59$^m$ 47$^s$ | −07° 01.7′ | 4 | MCG-01-06-017, MCG-01-06-019, MCG-01-06-020, MCG-01-06-022 | |
| 15 | 02$^h$ 07$^m$ 39.0$^s$ | +02° 08′ 18″ | 6 | UGC 1617, UGC 1618, UGC 1618 B, UGC 1620, UGC 1624, MCG+00-06-033 | |
| 16 | 02$^h$ 09$^m$ 31.3$^s$ | −10° 09′ 31″ | 4 | NGC 835, NGC 833, NGC 838, NGC 839 | Contains three starburst galaxies, two LINER galaxies, and a Seyfert 2 galaxy |
| 17 | 02$^h$ 14$^m$ 04.5$^s$ | +13° 18′ 54″ | 5 | PGC 8558, PGC 8559, PGC 8560, PGC 8561, PGC 8564 | |
| 18 | 02$^h$ 39$^m$ 06.10$^s$ | +18° 23′ 02.0″ | 4 | MCG+03-07-038, UGC 2140 | |
| 19 | 02$^h$ 42$^m$ 45$^s$ | −12° 24.7′ | 4 | MCG-02-07-073, MCG-02-07-074, MCG-02-07-075, PGC 10269 | |
| 20 | 02$^h$ 44$^m$ 14$^s$ | +26° 06.2′ | 6 | PGC 10364, PGC 10365, PGC 10366, PGC 10367, PGC 10368, PGC 10369 | |
| 21 | 02$^h$ 45$^m$ 16.9$^s$ | −17° 37′ 35″ | 5 | NGC 1099, NGC 1100, NGC 1098, NGC 1091, NGC 1092 | |
| 22 | 03$^h$ 03$^m$ 31$^s$ | −15° 40.5′ | 5 | NGC 1199, NGC 1190, NGC 1189, NGC 1191, NGC 1192 | |
| 23 | 03$^h$ 07$^m$ 06$^s$ | −09° 35.1′ | 5 | NGC 1214, NGC 1215, NGC 1216, MCG-02-08-054 | |
| 24 | 03$^h$ 20.3$^m$ | −10° 51′ | 5 | MCG-02-09-031, MCG-02-09-032, PGC 12472, PGC 12492, PGC 12489 | |
| 25 | 03$^h$ 20$^m$ 43.7$^s$ | −01° 03′ 07″ | 7 | UGC 2690, UGC 2691, PGC 12524, PGC 12530, PGC 12533, PGC 12538, PGC 12550 | |
| 26 | 03$^h$ 21$^m$ 54$^s$ | −13° 38.8′ | 7 | MCG-02-09-035, HCG 26b, PGC 12604, PGC 12605, PGC 12610, PGC 12613, PGC 12615 | |
| 27 | 04$^h$ 19.4$^m$ | −11° 42′ | 6 | PGC 14861, PGC 14862, PGC 14863, PGC 14866, PGC 14870, PGC 14873 | |
| 28 | 04$^h$ 27$^m$ 19$^s$ | −10° 19.0′ | 4 | PGC 15135, PGC 15136, PGC 15141, HCGd 28d | |
| 29 | 04$^h$ 34$^m$ 45$^s$ | −30° 32.8′ | 4 | PGC 15559, PGC 15560, PGC 15561, PGC 15562 | |
| 30 | 04$^h$ 36.5$^m$ | −02° 49′ | 4 | MCG+00-12-051, MCG+00-12-054, PGC 15624, PGC 15636 | |
| 31 | 05$^h$ 01$^m$ 37$^s$ | −04° 15.4′ | 4 | NGC 1741A, PGC 16570, NGC 1741B, PGC 16571 | |
| 32 | 05$^h$ 01.7$^m$ | −15° 25′ | 4 | MCG-03-13-053, PGC 16578, PGC 16584, PGC 16587 | |
| 33 | 05$^h$ 10$^m$ 47.6$^s$ | +18° 01′ 11″ | 4 | PGC 16863, PGC 16866, PGC 16867, PGC 16871 | |
| 34 | 05$^h$ 21$^m$ 47$^s$ | +06° 40.6′ | 4 | NGC 1875, VV 169b, VV 169c, VV 169d | |
| 35 | 08$^h$ 45$^m$ 20.71$^s$ | +44° 32′ 23.1″ | 6 | PGC 24596, PGC 24597, PGC 24598, PGC 24599, PGC 24600, PGC 24601 | |
| 36 | 09$^h$ 09$^m$ 24$^s$ | +15° 47.7′ | 4 | IC 528, IC 528C, PGC 25782, PGC 25791 | |
| 37 | 09$^h$ 13$^m$ 35.6$^s$ | +30° 00′ 51″ | 5 | NGC 2783, UGC 4856, MCG+05-22-016, MCG+05-22-018, MCG+05-22-020, | |
| 38 | 09$^h$ 27.6$^m$ | +12° 16′ | 4 | MCG+02-24-012, UGC 5044, MCG+02-24-014, PGC 26830 | |
| 39 | 09$^h$ 29$^m$ 28$^s$ | −01° 20.7′ | 4 | PGC 26925, PGC 26926, PGC 26929, PGC 26931 | |
| 40 | 09$^h$ 38$^m$ 54$^s$ | −04° 51.1′ | 6 | MCG-01-25-008, MCG-01-25-009, MCG-01-25-010, MCG-01-25-011, MCG-01-25-012, PGC 27517 | also known as Arp 321 |
| 41 | 09$^h$ 57$^m$ 40$^s$ | +45° 14.4′ | 4 | UGC 5345, UGC 5346, MCG+08-18-046, PGC 28784 | |
| 42 | 10$^h$ 00$^m$ 13.1$^s$ | −19° 38′ 24″ | 4 | NGC 3091, NGC 3096, MCG-03-26-006, PGC 28926 | also known as NGC 3091 Group |
| 43 | 10$^h$ 11.2$^m$ | −00° 01′ | 6 | Z 8-59, Z 8-61, Z 8-62, PGC 29666, PGC 29668, PGC 29673 | |
| 44 | 10$^h$ 18$^m$ 00$^s$ | +21° 48.7′ | 4 | NGC 3185, NGC 3187, NGC 3190, NGC 3193 | |
| 45 | 10$^h$ 19.2$^m$ | +59° 06′ | 4 | UGC 5564, PGC 30137, PGC 30143, PGC 30156 | |
| 46 | 10$^h$ 22.0$^m$ | +17° 48′ | 4 | MCG+03-27-005, MCG+03-27-007, MCG+03-27-008, MCG+03-27-009 | |
| 47 | 10$^h$ 25$^m$ 48$^s$ | +13° 43.9′ | 4 | UGC 5644, MCG+02-27-013, MCG+02-27-014, MCG+02-27-015 | |
| 48 | 10$^h$ 37$^m$ 45.6$^s$ | −27° 04′ 50″ | 4 | IC 2597, ESO 501-59, PGC 31577, PGC 31580 | |
| 49 | 10$^h$ 56$^m$ 36$^s$ | +67° 10.8′ | 4 | PGC 32890, PGC 32893, PGC 32895, PGC 32899 | |
| 50 | 11$^h$ 17$^m$ 06$^s$ | +54° 55.1′ | 5 | PGC 34444, PGC 34447, PGC 34448, PGC 34452, PGC 34453 | |
| 51 | 11$^h$ 22$^m$ 21.6$^s$ | +24° 19′ 41″ | 7 | NGC 3651, NGC 3653, IC 2759, MCG+04-27-030, MCG+04-27-027, PGC 34899, PGC 34901 | |
| 52 | 11$^h$ 26.3$^m$ | +21° 05′ | 4 | MCG+04-27-036, PGC 35178, PGC 35179, PGC 35184, | |
| 53 | 11$^h$ 28$^m$ 58$^s$ | +20° 46.6′ | 4 | NGC 3697, Mrk 1296, MCG+04-27-044, PGC 35381 | |
| 54 | 11$^h$ 29$^m$ 15$^s$ | +20° 34.7′ | 4 | IC 700 | |
| 55 | 11$^h$ 32$^m$ 07$^s$ | +70° 48.7′ | 5 | PGC 35573, PGC 35574, PGC 35575, 2MASX J11320571+7048236, HCG 55e | |
| 56 | 11$^h$ 32$^m$ 32$^s$ | +52° 56.9′ | 5 | MCG+09-19-113, Mrk 176, PGC 35609, PGC 35615, PGC 35618 | south of NGC 3718 and a popular target for amateur astronomers |
| 57 | 11$^h$ 37$^m$ 50.5$^s$ | +21° 59′ 06″ | 8 | NGC 3753, NGC 3746, NGC 3750, NGC 3754, NGC 3748, NGC 3751, NGC 3745, PGC 36010 | Also known as Copeland Septet |
| 58 | 11$^h$ 42$^m$ 09.4$^s$ | +10° 16′ 30″ | 5 | NGC 3817, NGC 3819, NGC 3820, NGC 3822, NGC 3825, | |
| 59 | 11$^h$ 48$^m$ 27$^s$ | +12° 43.0′ | 5 | IC 737, IC 736, PGC 36871, PGC 36867, PGC 36851 | |
| 60 | 12$^h$ 03$^m$ 05$^s$ | +51° 41.6′ | 4 | MCG+09-20-071, PGC 38053, PGC 38064, PGC 38072 | |
| 61 | 12$^h$ 12$^m$ 24$^s$ | +29° 10.7′ | 4 | NGC 4169, NGC 4170, NGC 4174, NGC 4175 | |
| 62 | 12$^h$ 53$^m$ 05.6$^s$ | −09° 12′ 21″ | 4 | NGC 4759, NGC 4761, NGC 4764, NGC 4776, NGC 4778 | |
| 63 | 13$^h$ 02.2$^m$ | −32° 46′ | 4 | ESO 381-50, ESO 443-37, PGC 44959, PGC 44979 | |
| 64 | 13$^h$ 25$^m$ 43$^s$ | −03° 51.5′ | 4 | PGC 46971, PGC 46972, PGC 46975, PGC 46977, | |
| 65 | 13$^h$ 29$^m$ 53$^s$ | −29° 30.0′ | 5 | ESO 444-55, PGC 47401, PGC 47403, PGC 47406, PGC 47407 | |
| 66 | 13$^h$ 38$^m$ 33$^s$ | +57° 18.3′ | 4 | MCG+10-19-104, PGC 48220, PGC 48231, PGC 48222 | |
| 67 | 13$^h$ 49$^m$ 03.5$^s$ | −07° 12′ 20″ | 4 | NGC 5306, MCG-01-35-013, MCG-01-35-015, PGC 49036 | |
| 68 | 13$^h$ 53$^m$ 40.9$^s$ | +40° 19′ 07″ | 5 | NGC 5350, NGC 5353, NGC 5354, NGC 5355, NGC 5358 | |
| 69 | 13$^h$ 55$^m$ 31$^s$ | +25° 03.8′ | 4 | UGC 8842, Z 132-48, MCG+04-33-028, PGC 49499 | HCG 69 is surrounded by other galaxies, such as IC 4343, IC 4344, IC 4345, IC 4346, IC 4348 and IC 4349 |
| 70 | 14$^h$ 04$^m$ 07.4$^s$ | +33° 19′ 10″ | 7 | IC 4369, IC 4370, IC 4371, UGC 8990, MCG+06-31-057, MCG+06-31-065, PGC 50123 | |
| 71 | 14$^h$ 11.1$^m$ | +25° 29′ | 4 | NGC 5008, IC 4382, PGC 50640, PGC 50641 | |
| 72 | 14$^h$ 47$^m$ 55$^s$ | +19° 03.6′ | 6 | UGC 9532, MCG+03-38-017, MCG+03-38-018, MCG+03-38-018, MCG+03-38-020, MCG+03-38-022 | |
| 73 | 15$^h$ 02$^m$ 40.1$^s$ | +23° 21′ 13″ | 5 | NGC 5829, IC 4526, PGC 53702, PGC 53703, PGC 53720 | |
| 74 | 15$^h$ 19$^m$ 28$^s$ | +20° 53.6′ | 5 | NGC 5910, MCG+04-36-036, PGC 54692, PGC 54694, PGC 54697 | |
| 75 | 15$^h$ 21$^m$ 37.0$^s$ | +21° 10′ 50″ | 6 | PGC 54802, PGC 54803, PGC 54804, PGC 54818, PGC 54824, PGC 54827 | |
| 76 | 15$^h$ 31.7$^m$ | +07° 18′ | 5 | NGC 5941, NGC 5942, NGC 5944, MCG+01-40-003, PGC 55313, PGC 55325 | |
| 77 | 15$^h$ 49$^m$ 17$^s$ | +21° 49.7′ | 4 | UGC 10049, PGC 56121, PGC 56122, PGC 56125 | |
| 78 | 15$^h$ 48.5$^m$ | +68° 12′ | 4 | UGC 10057, MCG+11-19-016, PGC 56086, PGC 56095 | |
| 79 | 15$^h$ 59$^m$ 13$^s$ | +20° 45.1′ | 5 | NGC 6027, NGC 6027a, NGC 6027b, NGC 6027c, NGC 6027d, NGC 6027e (tidal tail of NGC 6027) | Also known as UGC 10116, VV 115, Seyfert's Sextet or Serpens Sextet. Contains 2 lenticular galaxies, 3 spiral galaxies (one barred spiral) and a tidal tail. |
| 80 | 15$^h$ 59$^m$ 12$^s$ | +65° 13.6′ | 4 | PGC 56572, PGC 56577, PGC 56588, PGC 56590 | |
| 81 | 16$^h$ 18$^m$ 13$^s$ | +12° 47.6′ | 4 | SDSS J161813.66+124811.2, PGC 57774, PGC 57777, PGC 57779 | |
| 82 | 16$^h$ 28$^m$ 22.1$^s$ | +32° 49′ 25″ | 4 | NGC 6161, NGC 6162, NGC 6163, PGC 58231 | |
| 83 | 16$^h$ 35$^m$ 40.9$^s$ | +06° 16′ 12″ | 5 | PGC 58559, PGC 58561, PGC 58562, PGC 58565, PGC 58569 | |
| 84 | 16$^h$ 44$^m$ 08$^s$ | +77° 50.2′ | 6 | PGC 58856, PGC 58861, PGC 58873, PGC 58877, PGC 58881, PGC 58884 | |
| 85 | 18$^h$ 50$^m$ 22.3$^s$ | +73° 21′ 00″ | 4 | PGC 62476, PGC 62477, PGC 62478, PGC 62484, | |
| 86 | 19$^h$ 51$^m$ 59.2$^s$ | −30° 49′ 34″ | 4 | ESO 461-7, MCG-05-47-001, MCG-05-47-002, MCG-05-47-003, | |
| 87 | 20$^h$ 48$^m$ 11$^s$ | −19° 50.4′ | 4 | ESO 597-36, PGC 65409, ESO 597-35, PGC 65414 | One of the most compact groups, hosting two active galactic nuclei and a starburst among its three members, all of which show signs of interaction |
| 88 | 20$^h$ 52.4$^m$ | −05° 45′ | 4 | NGC 6978, NGC 6976, NGC 6977, MCG-01-53-014 | |
| 89 | 21$^h$ 20.2$^m$ | −03° 54′ | 4 | MCG-01-54-012, PGC 66574, PGC 66575, PGC 66580 | |
| 90 | 22$^h$ 02$^m$ 06.3$^s$ | −31° 55′ 48″ | 4 | NGC 7173, NGC 7174, NGC 7176, and NGC 7172 | also called NGC 7176 Group |
| 91 | 22$^h$ 09$^m$ 00.8$^s$ | −27° 47′ 36″ | 4 | NGC 7214, ESO 467-15, ESO 467-13, HCG 91d | also called VV 700 Group |
| 92 | 22$^h$ 35$^m$ 57.5$^s$ | +33° 57′ 36″ | 5 | NGC 7317, NGC 7318A, NGC 7318B, NGC 7319, NGC 7320C | Also called Stephan's Quintet, one galaxy of the sixsome, NGC 7320, is not part of the HCG but is a foreground galaxy in front of the five galaxies in the HCG. When discovered, two of the galaxies in the grouping were considered to be one galaxy, NGC 7318. |
| 93 | 23$^h$ 15$^m$ 12.2$^s$ | +18° 59′ 31″ | 5 | NGC 7547, NGC 7549, NGC 7550, NGC 7553, NGC 7558 | |
| 94 | 23$^h$ 17$^m$ 16.5$^s$ | +18° 43′ 11″ | 7 | NGC 7578, UGC 12477, PGC 70936, PGC 70937, PGC 70939, PGC 70941, PGC 70943, | |
| 95 | 23$^h$ 19$^m$ 32$^s$ | +09° 29.5′ | 4 | NGC 7609, MCG+01-59-046, PGC 71077, PGC 71080 | also called Arp 150 Group and NGC 7609 Group |
| 96 | 23$^h$ 27$^m$ 58$^s$ | +08° 46.4′ | 4 | NGC 7674, NGC 7674A, NGC 7675, PGC 71507 | |
| 97 | 23$^h$ 47$^m$ 24.0$^s$ | −02° 19′ 08″ | 5 | IC 5351, IC 5352, IC 5356, IC 5357, IC 5359 | |
| 98 | 23$^h$ 54.2$^m$ | +00° 22′ | 4 | NGC 7783, MCG+00-60-059, PGC 72810, NGC 7783 C | In 2019 a giant tidal tail and a large envelope was discovered around HCG 98 with the Wise Observatory |
| 99 | 00$^h$ 00$^m$ 43$^s$ | +28° 23.7′ | 4 | UGC 12897, UGC 12899, MCG+05-01-021, PGC 60, PGC 57 | |
| 100 | 00$^h$ 01.3$^m$ | +13° 07′ | 4 | NGC 7803, Mrk 934, MCG+02-01-009, MCG+02-01-010 | |

## Gallery

* NGC 201 is a barred spiral galaxy similar to the Milky Way, a member of HCG 7
* HCG 22 by Hubble Space Telescope
* Hickson Compact Group 59 by Hubble Space Telescope
* HCG 31 by Hubble Space Telescope
* HCG 31
* The four members of HCG 44 by Hunter Wilson
* NGC 6976 (lower right) and NGC 6977 (left) are part of HCG 88. Hubble image
* NGC 3718 and HCG 56 (bottom). Image from the legacy surveys