NGC 6051, IC 4588,
Galaxies in Serpens Cauda
Galaxy Cluster AWM 4
a Negative version of this image with the galaxies identified, click here.
This is a 15 minute exposure
with an ST-1301E CCD camera thru Kopernik's 20-inch F/8.1 Ritchey Chretien
Cassegrain telescope focal reduced to about F/5.1. The field of view is
about 20 x 23 arc minutes, with South at the top.
NGC 6051, IC 4588, and about 15
other galaxies form a small and very distant Galaxy Cluster (AWM 4) in
the Constellation of Serpens Cauda. Only one of the group is an obvious
Spiral Galaxy. All of the others are Elliptical Galaxies. The distance
to this small cluster is roughly 493 Million Light Years, (assuming
a Hubble Constant of H0 = 62 Km/Megaparsec - with relativistic adjustment).
NGC 6051 is 190,000 light years across. This group is a component of the
very large Hercules Super Cluster of Galaxies. There are a number of other
anonymous galaxies in the image, most of which have about the same red
shift - meaning that they are probably at about the same distance.
NGC 6051 is a giant type
of galaxy known as a "Cluster Dominant Elliptical". These galaxies
are possibly the result of the merger of several smaller galaxies and are
always found near the center of a galaxy cluster.
IC 4588 is sometimes described
as "non-existent". However it is very close to its IC position
southeast of NGC 6051. Dreyer added a note to (discoverer) Javelle's description
mentioning the NGC galaxy, and this has caused some confusion. The most
recent galaxy catalogs have given IC 4588 back its rightful place. Admittedly,
this distant elliptical galaxy appears very dim and tiny.
- NGC 6051
- Constellation: Serpens Cauda
16h 04m 56.6s
- Dec: +23° 55' 57" Epoch
- Size (mins): 1.3' x 0.8'
Classification: Cluster Dominant
Giant Elliptical Galaxy
Dreyer's Description in the NGC:
round, gradually brighter middle nucleus, 10th magnitude star southeast."
- IC 4588
- Magnitude: ??
10h 13m 44.9s
- Dec: +03° 25' 31" Epoch
- Size (mins): 0.2' x 0.2'
Classification: Dwarf Elliptical
- AWM 4
Classification: Galaxy Cluster
George Normandin, KAS
June 1st, 2006