The Caldwell Objects

tight gathering of a half-dozen roughly 7thmagnitude
stars just 30' to the southwest. This
grouping cannot be resolved by the naked eye
into individual stars. Instead, it looks like an
extended fuzzy glow, and its collected light
appears greater than that of NGC 7243. The
challenge, then, is to separate the cluster from
this asterism. Lie on a blanket in late summer,
when the Lizard climbs high in the evening
The Caldwell Objects
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sky, and plan to spend some time at this task
under the darkest conditions possible.
In 7x35 binoculars the cluster's brightest members
stand out from the starry background as a long
and slender arrowhead of partially resolved stars
pointing to the northeast. At 23x in the 4-inch
NGC 7243 is a loose aggregation of some 40
reasonably bright suns spread across 20' of sky,
though there are fainter members that extend the
cluster's dimensions another 10'. A north-southtrending
dark rift winds through the cluster's
midsection. The members lining the northern
side of the arrow are brighter than those to the
south. Most amusing is that the two halves of the
cluster seem to mimic each other in shape and
struc-
ture. The core of the
southwestern half is Vshaped,
with long looping
arms of stars that
look like the flapping
wings of a seagull. The
northeastern half of the
cluster is a similarly
shaped "bird." Using
one's imagination, both
birds appear to be flying
away from the observer
and into the cluster's
background of
unresolved suns.
The scene changes
quite dramatically at
72x, when the fainter stars forming the haze start
to sparkle into view. At this magnification the
cluster's core appears to be centered on a tight
triangle of stars at the apex of the southwestern
V. The easternmost star (arrowed in my sketch is
a fine double for small apertures. Known as
Struve 2890 (Σ2890), it consists of a magnitude-9.3
star with a magnitude-9.7 companion 9.2" away.
Extending outward from
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