Eridanus Cluster

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Eridanus Cluster
Observation data (Epoch J2000)
Constellation(s) Eridanus
Right ascension 03h 28m 13.8s[1]
Declination −20° 44′ 40″[1]
Brightest member NGC 1232 (B)
Number of galaxies ~200[2]
Velocity dispersion 261 km/s[3]
Redshift 0.005570[1]
Distance
(co-moving)
23 Mpc (75 Mly)[1]
ICM temperature ~107 K (~1 keV)[2]
Binding mass ~1014[3] M
X-ray flux 0.105 mCrab[2]
Other designations
Fornax II Cluster,[4] de Vaucouleurs Group 31[5]
See also: Galaxy groups, Galaxy clusters, List of galaxy clusters
The spiral galaxy NGC 1232 is one of the brightest in the Eridanus Cluster.

The Eridanus Cluster is a galaxy cluster roughly 23 Mpc (75 Mly) from Earth, containing about 73 main galaxies and about 200 total galaxies. About 30% have Hubble classifications of elliptical or S0 and the remaining 70% are spiral or irregular.[2] These galaxies reside in smaller groups which are all loosely gravitationally bound to each other, suggesting that the system is still condensing from the Hubble flow and may eventually form a cluster of about 1014 M. A low velocity dispersion compared to that of, for example, the Coma cluster, supports this hypothesis.[3] The Eridanus Cluster is located in the constellation Eridanus near the Fornax Cluster, and is sometimes called the "Fornax II Cluster".[4]

Table of galaxies[edit]

Column 1: Name of the galaxy
Column 2: Right ascension for epoch J2000
Column 3: Declination for epoch J2000
Column 4: Blue apparent magnitude of the galaxy
Column 5: Galaxy type: E=Elliptical; S0=Lenticular; Sa, Sb, Sc, Sd=Spiral (degree of woundedness of spiral arms); SBa, SBb, SBc, SBd=Barred Spiral; SAB= Intermediate Spiral (between barred and unbarred); Sm, SBm, Irr=Irregular; (r),(rs)=Ring Structure
Column 6: Angular diameter of the galaxy (arcminutes)
Column 7: Diameter of the galaxy (thousands of light years)
Column 8: Recessional velocity (km/s) of the galaxy relative to the cosmic microwave background

Name RA equatorial
coordinates
Dec equatorial
coordinates
Blue
Mag
Type Size
(arcmin)
Size
(kly)
RV
(km/s)
ESO 547-09 03 06.0 -19 23 16.8 Irr 1.3 35 1509
ESO 547-12 03 09.6 -17 50 16.5 Scd 1.5 35 1837
NGC 1232 03 09.8 -20 35 10.7 SAB(rs)c 6.9 170 1517
IC 1898 03 10.3 -22 24 13.7 SBc 3.4 85 1164
ESO 547-20 03 13.0 -17 56 16.0 SBm 1.2 30 1825
NGC 1258 03 14.1 -21 46 13.9 SBc 1.3 30 1340
NGC 1297 03 19.2 -19 06 13.5 E 2.0 50 1395
NGC 1300 03 19.7 -19 25 11.2 SBbc 6.0 110 1421
NGC 1315 03 23.1 -21 23 14.0 S0 1.5 35 1534
PGC 12680 03 23.4 -19 17  ? Irr 1.3 30 1400
ESO 548-05 03 23.8 -19 45 14.7 SBm 1.5 35 1690
NGC 1325 03 24.4 -21 33 12.3 SBbc 4.7 115 1446
NGC 1325A 03 24.8 -21 20 13.6 SBcd 1.8 45 1188
ESO 548-16 03 26.0 -21 20 15.6 Scd 1.7 40 1977
NGC 1332 03 26.3 -21 20 11.4 E 4.2 105 1383
ESO 548-21 03 27.6 -21 14 14.7 SBd 2.0 50 1541
ESO 548-25 03 29.0 -22 09 15.0 SBa 1.3 30 1542
NGC 1345 03 29.5 -17 47 14.3 SBc 1.4 35 1385
ESO 481-30 03 29.6 -23 21 15.5 Scd 1.5 35 1504
NGC 1347 03 29.7 -22 17 13.9 SBc 1.4 35 1624
ESO 548-28 03 30.6 -17 56 14.0 S0 1.3 35 1360
ESO 548-29 03 30.8 -21 03 14.3 SBbc 1.1 30 1175
NGC 1353 03 32.1 -20 49 12.4 SBb 3.5 85 1390
ESO 548-32 03 32.3 -17 43 15.8 SBm 1.6 40 1815
ESO 548-33 03 32.5 -18 57 14.5 S0 1.3 35 1552
ESO 548-34 03 33.0 -21 05 14.6 SBc 1.1 30 1610
ESO 482-05 03 33.0 -24 08 15.2 SBcd 2.1 50 1783
IC 1952 03 33.4 -23 43 13.5 SBbc 2.5 60 1683
IC 1953 03 33.7 -21 29 12.7 SBc 2.6 65 1733
NGC 1359 03 33.8 -19 29 13.0 SBm 2.1 55 1833
NGC 1362 03 33.9 -20 17 14.2 S0 1.2 30 1085
ESO 548-44 03 34.3 -19 25 14.2 S0 1.3 35 1561
ESO 548-47 03 34.7 -19 02 14.1 S0 2.5 60 1472
NGC 1371 03 35.0 -24 56 11.6 SBa 5.6 140 1344
NGC 1370 03 35.2 -20 22 13.9 E 1.5 35 933
IC 1962 03 35.6 -21 18 14.8 SBd 2.5 60 1670
ESO 482-11 03 36.3 -25 36 14.7 Sbc 1.4 35 1469
NGC 1377 03 36.7 -20 54 13.8 S0 1.7 45 1645
NGC 1385 03 37.5 -24 30 11.5 SBc 3.7 90 1373
NGC 1383 03 37.7 -18 20 13.8 S0 1.7 40 1828
ESO 482-17 03 37.7 -22 55 14.9 Sab 1.3 30 1330
NGC 1390 03 37.9 -19 00 14.9 SBa 1.3 35 1078
NGC 1395 03 38.5 -23 02 10.7 E 5.6 140 1577
NGC 1398 03 38.9 -26 20 10.5 SB(r)ab 7.1 135 1289
NGC 1403 03 39.2 -22 23 14.1 E 1.3 30 1751
NGC 1401 03 39.4 -22 43 13.7 S0 1.9 50 1406
NGC 1400 03 39.5 -18 41 12.3 E 2.3 60 415
ESO 548-63 03 39.6 -20 01 15.1 Sbc 1.4 35 1846
ESO 548-65 03 40.0 -19 22 15.3 Sa 1.4 35 1102
IC 343 03 40.1 -18 27 14.3 S0 1.4 35 1730
NGC 1407 03 40.2 -18 35 10.9 E 5.1 125 1650
ESO 548-68 03 40.3 -18 56 14.3 E 1.3 35 1636
NGC 1412 03 40.5 -26 52 14.7 S0 1.4 35 1675
ESO 548-70 03 40.7 -22 17 15.4 SBcd 1.6 40 1615
ESO 482-32 03 40.7 -26 47 15.9 Irr 1.2 30 1621
NGC 1415 03 40.9 -22 34 12.8 Sa 3.3 80 1451
NGC 1414 03 41.0 -21 43 14.6 SBbc 1.6 40 1464
ESO 482-35 03 41.2 -23 50 14.2 SBab 1.8 45 1756
NGC 1422 03 41.5 -21 41 14.2 SBab 2.3 55 1514
IC 346 03 41.7 -18 16 13.9 S0 1.9 45 1830
ESO 548-79 03 41.9 -18 54 14.8 Sa 1.1 30 1914
ESO 548-82 03 42.7 -17 30 15.4 Sbc 1.1 30 1590
NGC 1426 03 42.8 -22 06 12.7 E 2.5 60 1296
ESO 549-02 03 43.0 -19 01 14.9 SBm 1.3 30 988
ESO 549-06 03 43.6 -21 14 15.7 Irr 1.3 30 1490
NGC 1439 03 44.8 -21 55 12.4 E 2.6 65 1577
NGC 1440 03 45.0 -18 16 12.9 S0 2.2 55 1403
NGC 1438 03 45.3 -23 00 13.3 SBa 2.0 50 1438
NGC 1452 03 45.4 -18 38 12.9 Sa 2.3 60 1619
ESO 549-18 03 48.2 -21 28 13.3 SBc 2.5 60 1473
ESO 482-46 03 49.7 -27 00 13.7 Sc 3.5 90 1422
ESO 482-49 03 52.4 -23 03 15.3 Sc 1.1 30 1377
NGC 1482 03 54.6 -20 30 13.3 S0 2.2 55 1753

See also[edit]

References[edit]

  1. ^ a b c d "Eridanus Cluster". NASA/IPAC Extragalactic Database (NED). Retrieved 2012-02-25. 
  2. ^ a b c d Omar, A.; Dwarakanath, K. S. (March 2005). "GMRT HI Observations of the Eridanus Group of Galaxies I" (PDF). Journal of Astrophysics and Astronomy. 26 (1): 1–33. arXiv:astro-ph/0503536Freely accessible. Bibcode:2005JApA...26....1O. doi:10.1007/BF02702451. Retrieved 2012-02-25. 
  3. ^ a b c Willmer, C. N. A.; Rocardi, P.; da Costa, L. Nicolaci; Pellegrini, P. S. (November 1989). "Studies of nearby poor clusters - The Eridanus group" (PDF). Astronomical Journal. 98 (Nov. 1989): 1531–1541. Bibcode:1989AJ.....98.1531W. doi:10.1086/115236. ISSN 0004-6256. Retrieved 2012-02-25. 
  4. ^ a b atlasoftheuniverse.com
  5. ^ Chincarini, G.; Rood, H. J.; Welch, G. A. (March 1975). "A re-analysis of the dynamics of the nearby groups of galaxies" (PDF). Monthly Notices of the Royal Astronomical Society. 170 (Mar. 1975): 441–445. Bibcode:1975MNRAS.170..441C. doi:10.1093/mnras/170.3.441. A&AA ID. AAA013.160.006. Retrieved March 10, 2012. 

Coordinates: Sky map 03h 28m 13.8s, −20° 44′ 40″