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NGC 288
Ben 5
RA 00:52:46
Dec -26° 35.4'
Globular cluster
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Discovered in 1785 by William Herschel (H
VI-020) with an 18.7-inch f/13 speculum telescope. He called it "cB, iR, 8
or 9' diameter, a great many of the stars visible, so that there can remain no
doubt but that it is a cluster of vS stars."
h: "globular cluster; bright; large;
round; gradually brighter in the middle; all resolved into stars 12..16 mag; 5'
diameter."
Houston notes that this "8th mag ball of
stars about a quarter of a degree in diameter lies about two degrees southeast
of NGC 253. Steve Gottlieb of Albany, California, reports that his 13-inch
Dobsonian at 166x resolved some 40 to 50 stars against a background of hazy
light." In 1976 Houston wrote: " . . binoculars were sufficient to
distinguish NGC 288, which I make to be 12' in diameter and of visual magnitude
7.0. In a pair of 5-inch 20power binoculars, it was possible to see individual
stars around the edge of the cluster. With a 12.5-inch f/8 the cluster could be
resolved almost to its centre. Only the regularity of the star pattern indicated
that NGC 288 was a globular cluster. ."
William P. Clarke (San Diego, California, USA)
writes in the The Webb Society Nebulae and Clusters Section Report No. 10, July
1992: "A large, irregular-looking globular with no core. Many tiny stars
resolved. (10-inch, x48)."
Tom Lorenzin, in the electronic version of "1000+
The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "8M;
14' diameter; easily resolved at 100x into compressed glitter of 12M and dimmer
stars; 1.75 degrees SE of N253; S Galactic Pole is 40' to SW (don't look for
it!)."
Steve Coe, observing with a 17.5" f/4.5
at 100X, notes: "Pretty faint, large, not much brighter in the middle,
irregularly round, 40 stars resolved at 135X. It can be seen in a pair of 10X50
binoculars as a dim, small spot. Even this low surface brightness globular
cluster is a welcome as a break in all these galaxies.
11x80: A delicate, round
puffy globular cluster, some 8 arcmin across, amongst the stars of a
parallelogram. (exurban skies, seeing 7, transparency 7, sky darkness 6,
lim.mag. at south pole 6.0 (naked eye)) [AS]
10-inch f/5 Newtonian: At
30x the 10-inch shows this as a considerably bright, very large unresolved
cluster, presenting a surface which does not even appear mottled. The higher
contrast at 120x shows it clearly composed of pretty evenly scattered, very
small stars. At times it appears somewhat elongated, but this is doubtful..
(suburban skies) [AS] |
