Hickson 61, sometimes called "The Box", is a
very tight grouping of four galaxies that form a nearly perfect
rectangle. Contained within a field of just 3.8', they all will
fit into the same medium-power field. Particularly striking in
the eyepiece is how the two highly elongated galaxies line up,
nearly forming one long streak. The brightest member, the
13.3-magnitude Lenticular galaxy NGC 4169, can probably be
glimpsed in an 8-inch. The next easiest to detect is the tiny
NGC 4174, a nearly edge-on 14.5 magnitude spiral. NGC 4175 is
14.3-magnitude edge-on spiral that shows evidence of interaction
with a neighbor. Finally, NGC 4173 is the largest of the four,
but the most difficult. Another interacting spiral galaxy, this
13.8 magnitude galaxy has a very low mean surface brightness. It
is this galaxy and the nearby NGC 4175 that together form a
nearly perfect line. Interestingly, the three other galaxies all
have recession velocities of around 2900 km/sec, but at 1100
km/sec NGC 4173 is receding much more slowly. Recessional
velocities indicate, NGC 4173 is a foreground object not
physically associated despite the coincidental evidence of
interaction.
