The Caldwell Objects

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2 5
Intergalactic Tramp;
Intergalactic
Wanderer
NGC 2419
Type: Globular Cluster
Con: Lynx
RA: 07 h 38 m 08.5 s
Dec: +38° 52' 55"
Mag: 10.4
Diam: 4.6'
Dist: 275,000 light-years
Disc: William
Herschel, 1788
W. H ERSCHEL: [Observed 31 December 1788] Considerably
bright. Round. Very gradually much brighter in the middle.
About 3' diameter. (Η 1-218)
GC: Pretty bright, pretty large, little extended toward position
angle 90°, very gradually brighter in the mid-
OF THE 150 OR so GLOBULAR CLUSTERS KNOWN or
believed to be associated with our Milky Way
galaxy, NGC 2419 is among the most remote. In
1918 Harvard College Observatory astronomer
Harlow Shapley began determining the distances
to these spherical swarms, each containing tens
or hundreds of thousands of ancient stars. He
found that globular clusters appeared to be
distributed within a sphere 65,000 light-years in
radius that was centered on the galactic center.
This significant discovery demonstrated that our
Sun was not at the center of the universe as many
had previously believed.
Shapley knew NGC 2419 was a "distant"
cluster and assigned it a distance of 99,000 lightyears
in his 1930 monograph, Star Clusters. But it
was Walter Baade who first discovered
104
dle, a star of magnitude 7 or 8 toward position angle 19°.
NGC: Pretty bright, pretty large, little extended toward position
angle 90°, very gradually brighter in the middle, a star of
magnitude 7 or 8 toward position angle 267°, 4' distant.
just how extremely distant NGC 2419 really was.
His 1935 observations from Mount Wilson placed
the globular 182,000 light-years from the Sun —
about as far as the Large Magellanic Cloud, the
Milky Way's preeminent satellite galaxy. NGC
2419 indeed is a maverick, lying well beyond the
edge of the Milky Way's starry disk. But even
Baade's distance determination seems
conservative with hindsight. More recent studies
have pushed the cluster out even farther. The
1999 Catalog of Parameters for Milky Way Globular
Clusters compiled by William E. Harris
(McMaster University, Canada) places NGC 2419
some 275,000 light-years from the Sun. If true,
this means the globular is fully 100,000 lightyears
more distant than the Large Magellanic
Cloud. Even more remote are globular clusters
Pal 3
Deep-Sky Companions: The Caldwell Objects