The Caldwell Objects

(300,000 light-years), Pal 4 (360,000 light-years),
and AM 1 (400,000 light-years).
Some astronomers understandably refer to
these extremely distant globulars as "intergalactic
wanderers." And, though the common nickname
for NGC 2419 is the Intergalactic Wanderer, Brent
Archinal points out that we seem to have
forgotten the cluster's original name: the
Intergalactic Tramp, a name bestowed upon it by
Shapley in 1944. "By 1958," Archinal writes,
"Helen Sawyer Hogg, in her Monograph on
clusters, indicated that [the Intergalactic Tramp]
had become the accepted common name for the
object (although she seems to attribute the name
to Baade). I don't think it should go without
mention that in many modern publications,
Shapley's name has been changed to the
Intergalactic Wanderer. I have not tried to trace
the origin of this name but it would be interesting
to do so. I suspect that this is just the 'politically
correct' version of Shapley's name, because of
differences in meaning that the word 'tramp' has
now vs. the 1940s. Shapley was apparently trying
to emphasize
The Caldwell Objects
25
that NGC 2419 was so far from the center of the
Milky Way, and was probably moving so slowly
that it was almost not moving, or at least moving
without any planned direction (like a railroad
'tramp,' or perhaps a 'tramp steamer' of his day).
That is of course not quite the meaning of the
word 'wanderer,' which implies something
different."
Is NGC 2419 lost in space? No. "With steady
improvements in the data," Harris writes, "and
the growing understanding of things like dark
matter and the mass profile of the Milky Way
and other galaxies, [that idea] has rather faded
away. All the known globular clusters in the
Milky Way (including NGC 7006, 2419, and all
the other remote ones) are now realized to be
quite securely bound to the Milky Way." Harris
does believe that free-floating intergalactic
clusters could and probably do exist, but we
haven't found any decent candidates yet.
Needless to say, NGC 2419 is not a knock-yourglasses-off
spectacle. Considering its great
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