| Hickson 94 | ||
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Hickson 94 is a compact galaxy group with a total of seven members. Measurements of the gas temperature between the galaxies and the unabsorbed X-ray luminosity indicate that this is a true galaxy cluster. The redshift (Z) of the member galaxies is 0.04, representing a light travel time of 600 million years from the cluster to your eye. The cluster was apparently discovered by William Herschel, who merely noted, "4 or 5 small stars with nebulosity."
Nearby lie two other galaxies within reach of larger amateur instruments. PGC 70943 is a 16.2 magnitude spiral galaxy that subtends 28" x 13". Despite the faint magnitude, the surface brightness of this galaxy is relatively high (22.3 mag/arc-sec2). This galaxy is listed as interacting with an associated bar. As with the others the core of PGC 70943 is most easily seen and appears stellar. PGC 70936 is a tiny (10" x 6") 16.3 magnitude lenticular galaxy that lies very close to the NGC 7578A/B pair. This tiny galaxy appears in the eyepiece as a very faint star. Unfortunately, a nearby star is easily confused with it (see image).
The
image above shows how small and starlike these galaxies are.
The field (gray circle) in an 18-inch f/4.5 at 60x. North is down and east is to the right. At the eyepiece the cluster appears as a few faint stars embedded in a very faint haze. A night of good seeing and high magnification (at least 250x) are recommended. |
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