A Maffei I galaxishalmaz
A hozzánk igen közeli Maffei I galaxishalmaz rövid bemutatása, katalógusa, referenciák. Az oldal angolul van, de a katalógus angolul nem értők számára is hasznos lehet.
The galaxies of this group have probably once formed a subgroup of our Local Group, which during the dynamical history of the group, have been ejected because of a violent encounter with the Andromeda Galaxy M31. Since, they have moved away to an about 10 million light years distance.
As the Maffei 1 group lies very close to the Galactic plane (the equatorial plane of our Galaxy), it is highly obscured by the dark dusty matter of our Milky Way. Only one of them, IC 342, has got an IC number, and none is in the NGC.
The known galaxies in this group are (in the order of their discovery):
- IC 342 (UGC 2847). Discovered by W.E. Denning in 1895.
- Maffei 1 (UGCA 34). Discovered by Paolo Maffei in 1968.
- Maffei 2 (UGCA 39) Discovered by Paolo Maffei in 1968.
- Dwingeloo 1 (PGC 100170, Cas 2) Discovered in 1994.
- Dwingeloo 2 (PGC 101304) Discovered 1995 when investigating the field around Dwingeloo 1.
UGCA 86 (discovered 1974 by P.N. Nilson), listed in our Local Group list, is also not lying far from IC 342. It would be interesting to know its distance a bit more acurate, and to investigate its possible involvement in the encounter scenario.
Probably situated somewhat closer, spacially between our Local Group and the Maffei 1 group, are some galaxies around the nearby dwarf galaxies NGC 1569 and NGC 1560:
- NGC 1569 (H. II.768). The first of these galaxies to be discovered, on November 4, 1788 by William Herschel. Taken for a possible Local Group member by Halton Arp in 1966.
- NGC 1560 (Tempel 1882, AN No. 2660). Ernst Wilhelm Leberecht Tempel discovered this galaxy in 1882. Taken for a possible Local Group member by Halton Arp in 1966.
- UGCA 92? Discovered 1774 by P.N. Nilson. On occasions, this galaxy was listed as a possible Local Group member.
- Cam A. Discovered 1991.
More fainter and typically smaller galaxies have been discovered semi-recently that may belong to the Maffei 1 group, or perhaps the group around NGC 1560:
- Cas 3 (KKH 5)
- KKH 6
- Cas 1 (KK 19)
- Perseus 1 (KKH 11)
- Perseus 2 (KKH 12)
- UGC 2773 (KK 28)
- MB 1 (KK 21). Dicovered 1995 by McCall and Buta.
- MB 2 Dicovered 1995 by McCall and Buta.
- MB 3 (KK 22) Dicovered 1997 by McCall and Buta.
- KK 35
- Cam B (KK 44)
- UGCA 105
- Cam D (KKH 34)
- Mailyan 16 (KKH 37)
Astronomical data for the Maffei 1 group galaxies:
Name Con RA (2000) Dec Type mag dim v_r
IC 342 Cam 03:46.8 +68:06 Sc 9.1 21.4x20.9 + 31
Maffei 1 Cas 02:36.3 +59:39 E/S0 11.4 3.4x1.7 + 13
Maffei 2 Cas 02:41.9 +59:36 SBb 16.0 5.8x1.6 - 17
Dwingeloo 1 Cas 02:56.9 +58:55 SBb 8.3 4.2x0.34 +110
Dwingeloo 2 Cas 02:54.1 +59:00 Im 20.5 6.4 + 94
Astronomical data for the additional candidates listed above:
Cam A Cam 04:25.3 +72:48 E 14.8 3.7x2.1 -192
NGC 1569 Cam 04:30.8 +64:51 Irr 11.2v 2.9x1.5 -153
UGCA 92? Cam 04:32.0 +63:36 Irr 13.8 2.0x1.0 -164
NGC 1560 Cam 04:32.8 +71:53 Scd 11.5v 9.8x2.0 - 94
Cas 3 Cas 01:07.5 +51:26 Irr 17.1p 1 -166
KKH 6 Cas 01:34.9 +52:06 Irr 17.0p 1 -141
Cas 1 Cas 02:06.1 +69:01 Irr 16.4p 5.5 - 95
Perseus 1 Per 02:24.6 +56:01 Irr 16.2p 2.2 - 93
Perseus 2 Per 02:27.4 +57:29 Irr 17.8p 3.4 - 90
UGC 2773 And 02:32.1 +47:48 Irr 14.3p 1.2 + 83
MB 1 Cas 02:35.6 +59:23 Irr 19.5p 1.9 + 39
MB 2 Cas 02:37.0 +59:14 Irr?
MB 3 Cas 02:55.7 +58:52 dSph 19.8p 3.9 - 43
KK 35 Cam 03:45.2 +67:52 Irr + 32
Cam B Cam 04:53.1 +67:06 Irr 16.7p 2.6 + 27
UGCA 105 Cam 05:14.2 +62:35 Sm 13.2p 7.4 + 76
Cam D Cam 05:59.7 +73:26 Irr 17.1p 1 + 93
Mailyan 16 Cam 06:47.8 +80:07 Irr 16.4p 1 -157
References:
- Ronald Buta and Marshall McCall, 1999. The IC 342/Maffei Group Revealed. Astrophysical Journal Supplement, Vol. 124, No. 1, p. 33-93 (September 1999)
- W. Huchtmeier, D. Westphahl, I. Karachentsev, and V. Karachentseva, 2001. The IC 342/Maffei Group of Galaxies. Gas and Galaxy Evolution, ASP Conference Series, Vol. 240, p. 589.
Frank Richardsen, 2003. Die IC 342/Maffei-Galaxiengruppe [The IC 342/Maffei Group of Galaxies]. Teil [Part] I: Interstellarum No. 30, p. 46-48 (October 2003). Teil II: Interstellarum No. 31, p. 44-47 (December 2003). Teil III: To appear in 2004.