The Caldwell Objects

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Box Galaxy
NGC 4449
Type: Irregular Barred
Dwarf Galaxy (IBm)
Con: Canes Venatici
RA: 12 h 28.2 m
Dec: +44° 06'
Mag: 9.6
Dim: 5.4' x 4.2'
SB: 12.8
Dist: 10 million light-years
Disc: William Herschel, 1788
W. H ERSCHEL: [Observed
27 April 1788] Very bril-
liant. Considerably large.
Extended from south pre-
ceding to north following
[from southwest to north-
east]. With difficulty resolv-
able. Has 3 or 4 bright compressed spots. (Η I-213)
GC: Very bright, considerably large, moderately
extended toward position angle 15°, well resolved, star
of magnitude 9 following [to the east] 5'.
A S ONE CAN GLEAN FROM THE HERSCHEL,
GC, and N G descriptions C tabulated above, NGC
4449 is one object that deceived 19th-century
astronomers into believing they had resolved a
"nebula" into stars. At the time galaxies as island
universes were unknown to astronomers. Many
of these systems belonged to what they
considered the realm of "spiral nebulae," which
seemed to fit a cosmological model introduced by
the French mathematician Pierre Simon Laplace.
Laplace's model postulated that our solar system
condensed out of a nebulous vortex, and the
spirals, many presumed, were solar systems
being born. Indeed, not until 1923, when the
outer regions of M31
The Caldwell Objects
NGC: Very bright, considerably large, moderately extended,
double or [bifurcated?], well resolved, clearly consisting of
stars, star of magnitude 9 following [eastward] 5'.
21
were first resolved with the 100-inch reflector on
California's Mount Wilson, was the true nature of
the mysterious spirals revealed. In fact, until that
time M31 was commonly referred to as the Great
Spiral N e b in u Andromeda. l a
Unfortunately, no 19th-century telescope
was powerful enough to reveal individual stars
in a distant galaxy like NGC 4449. Looking at a
photograph of this irregular system, it's easy to
understand how the astronomers of that era were
deceived; the galaxy looks like a clouded
hourglass wrapped in knotty stellar filigree. One
can only imagine the excitement these
astronomers must have felt when they imagined
the galaxy resolved into stars. Of course,
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