Last month I mentioned IC 342 as previously having been a member of our Local Group, which consists of our Milky Way, Andromeda, M33, and a about 27 other small guys. We used to have more members, but apparently the Board of Supervisors of our group decided to eject a few members and banish them altogether. Who are they and what did they do you ask? Well here's who they are:

Name             Con     RA(2000)    Dec     Type    mag    dim
IC 342            Cam     03:46.8     +68:06   Sc        9.1       21.4x20.9
Maffei 1          Cas      02:36.3     +59:39   E/S0    11.4      3.4x1.7
Maffei 2          Cas      02:41.9     +59:36   SBb     16.0      5.8x1.6
Dwingeloo 1   Cas      02:56.9     +58:55   SBb     8.3        4.2x0.34
Dwingeloo 2   Cas      02:54.1     +59:00   Im        20.5       6.4

What they did was they got into some sort of fracas, mostly with Andromeda, about 5 to 10 billion years ago. At the time, Andromeda was busy swallowing whole a dwarf galaxy, and during the cataclysm, these fellows got heaved out.

Note that none of these have NGC numbers! Paolo Maffei discovered the two bearing his name in 1968 and astronomers at the Dwingeloo Radio Observatory in the Netherlands discovered the two bearing its name in 1994! The two Dingeloo galaxies are estimated at about 12 MLY, but there is some uncertainty, since they lie so close to the plane of the Milky Way. (The reason this matters is that distance analysis often rely on examinations of Cepheid variables in a galaxy, but the dust in our own interferes with brightness measurements.)

It might be interesting to try to track down these fellows. IC 342 is an easy catch, Maffei 1 might also be pretty easy. However Dwingeloo 1 may present a challenge, it's really skinny! Dwingeloo 2 is visible only in radio telescopes and appears to be a dwarf companion of Dwingeloo 1. IC 342 was shown on last month's chart, however, none of the star chart programs I have include any of the others, I haven't presented a star chart.