NGC 68 group
| NGC 68 group | |
|---|---|
 | |
| Observation data (Epoch ) | |
| Constellation(s) | Andromeda |
| Right ascension | main group 00h 18m 30s cluster center 00h 18m 45s |
| Declination | main group 30° 03′ 00″ cluster center 30° 00′ 00″ |
| Brightest member | NGC 68 |
| Number of galaxies | 40 (confirmed) 60+ (possible)[1] |
| Richness class | Group 0/1 |
| Bautz–Morgan classification | type II/III |
| Velocity dispersion | ~6750[1] |
| Redshift | 0.019 to 0.025 |
| Distance | ~300,000,000 ly |
The NGC 68 galaxy group is a cluster of at least 40 galaxies around the elliptical galaxy NGC 68. The main group was discovered in 1784 by William Herschel, who listed the galaxies as a single object. Later, in the 1880s, John Louis Emil Dreyer managed to discern the main galaxies and cataloged them each as NGC 68, NGC 70, and NGC 71.[2]
Members
| galaxy | RA | DEC | redshift | size (ly) | distance (mly) |
|---|---|---|---|---|---|
| NGC 67 | 00h 18m 12.18s | 30° 03′ 17.5″ | 0.020734[1] | 40,000 | 275[3] |
| NGC 67a | 00h 18m 14.83s | 30° 03′ 45″ | 0.022162 | 35,000 | 300 |
| NGC 68 | 00h 18m 18.48s | 30° 04′ 15.4″ | 0.01913 | 90,000 | 260 |
| NGC 69 | 00h 18m 20.5s | 30° 02′ 21.2″ | 0.022285 | 80,000 | 300 |
| NGC 70 | 00h 18m 22.6s | 30° 04′ 44″ | 0.023907 | 180,000 | 320 |
| NGC 71 | 00h 18m 23.6s | 30° 03′ 45″ | 0.022339 | 130,000 | 300 |
| NGC 72 | 00h 18m 28.36s | 30° 02′ 23.7″ | 0.024213 | 120,000 | 325 |
| NGC 72a | 00h 18m 34.35s | 30° 02′ 08″ | 0.022399 | 25,000 | 300 |
| NGC 74 | 00h 18m 49.39s | 30° 03′ 39.1″ | 0.023646 | 65,000 | 315 |
| GALEXASC J001817.48+295854.3 | 00h 18m 17s | 29° 58′ 50″ | 0.024981 | 30,000[4] | 335 |
| PGC 1183 | 00h 18m 14.05s | 29° 57′ 05″ | 0.020374 | 68,000 | 275 |
| PGC 1163 | 00h 17m 46.02s | 30° 09′ 4.5″ | 0.021885 | 73,000 | 295 |
| 2MASX J00174636+2957409 | 00h 17m 46.3s | 29° 57′ 39″ | 0.024113 | 61,000 | 325 |
| 2MASX J00183652+2955586 | 00h 18m 36.5s | 29° 55′ 55.2″ | 0.021475 | 32,000 | 290 |
| 2MASX J00181971+2954372 | 00h 18m 19.67s | 29° 54′ 35″ | 0.022192 | 50,000 | 300 |
| 2MASX J00181589+2954145 | 00h 18m 15.92s | 29° 54′ 12.5″ | 0.024093 | 43,000 | 325 |
| 2MASX J00191196+3000506 | 00h 18m 11.97s | 30° 00′ 47.8″ | 0.023456 | 47,000 | 315 |
| 2MASX J00191966+3005286 | 00h 19m 19.64s | 30° 05′ 26″ | 0.02389 | 60,000 | 320 |
| GALEXASC J001833.49+295028.7 | 00h 18m 31.52s | 29° 50′ 24.3″ | 0.020981 | 32,000 | 285 |
| 2MASX J00174173+2951151 | 00h 17m 41.71s | 29° 51′ 12.4″ | 0.022359 | 37,000 | 300 |
| PGC 1138 | 00h 17m 17.38s | 30° 12′ 30.5″ | 0.020988 | 56,000 | 285 |
| PGC 1119 | 00h 17m 02.63s | 29° 56′ 29.7″ | 0.023116 | 82,000 | 310 |
| NGC 76 | 00h 19m 37.81s | 29° 55′ 59.3″ | 0.02444 | 118,000 | 330 |
| 2MASX J00164915+3010462 | 00h 16m 49.16s | 30° 10′ 43.5″ | 0.024133 | 42,000 | 325 |
| PGC 1266 | 00h 19m 43.06s | 29° 56′ 4.1″ | 0.022339 | 43,000 | 300 |
| 2MASX J00181849+2942002 | 00h 18m 18.47s | 29° 41′ 57.7″ | 0.022749 | 46,000 | 305 |
| GALEXASC J001940.31+294928.1 | 00h 19m 40.35s | 29° 49′ 26.1″ | 0.025621 | 51,000 | 345 |
| PGC 1090 | 00h 16m 32.85s | 30° 20′ 42.5″ | 0.021331 | 84,000 | 290 |
| PGC 1220 | 00h 18m 55.28s | 30° 30′ 46.6″ | 0.02408 | 50,000 | 325 |
| 2MASX J00160018+3002561 | 00h 16m 00.31s | 30° 02′ 54.9″ | 0.022676 | 43,000 | 305 |
| GALEXASC J002032.09+300302.0 | 00h 20m 32.06s | 30° 02′ 58.8″ | 0.021058 | 34,000 | 285 |
References
- ^ a b c "objects within 30 arcminutes of NGC 72a". NED. NASA/IPAC. Retrieved 18 May 2014.
- ^ Seligman, Courtney. "New General Catalog Objects: NGC 50 - NGC 99". Cseligman.com. Retrieved 18 May 2014.
- ^ Wright, Ned. "Ned Wright's Javascript Cosmology Calculator". http://www.astro.ucla.edu. UCLA. Retrieved 18 May 2014.
{{cite web}}: External link in|work= - ^ "Angular Size Calculator". www.1728.org. Retrieved 18 May 2014.