13.09.2007 - Emberger Alm
Stephan's Quintet, as its name implies, is a group of five galaxies (NGC7317, 7318A, 7318B, 7319 and 7320) in the constellation Pegasus. This unusual system has often been used as proof that the redshift is not truly a distance indicator, which would completely overturn current cosmology, because although four of the galaxies have similar, large redshifts, the fifth (NGC7320), although apparently a member of the group, shows a much smaller redshift. Conventional theory states that the low-redshift galaxy is in a nearby group (the NGC7331 group) and by coincidence appears on the sky projected against a distant background group. Opponents point to debris and tails around the low-redshift galaxy, suggesting that it is interacting with the high-redshift systems, which would require that all five galaxies be at the same physical location in space.
12,5" f/4 Astrograph CTA320, STL-11000M, L:R:G:B- 100:30:30:30 min
Galaxy group
Size: 10' x 4,5'
Constellation: Pegasus
Magnitude: 13
Distance: approx. 300 Mio. light years