The Caldwell Objects

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NGC 2775
Type: Spiral Galaxy (Sab)
Con: Cancer
RA: 09 h 10.3 m
Dec: +07° 02'
Mag: 10.1 Dim:
4.6'x 3.8' SB:
13.1
Dist: 55 million light-years
Disc: William Herschel,
1783
W. H ERSCHEL: [Observed 19
December 1783] Considerably
bright, considerably large,
very gradually brighter in the
middle, having a nucleus or a
bright compressed spot. Round. (H1-2)
GC/NGC: Considerably bright, considerably
large,
BEFORE THE INTERNATIONAL ASTRONOMICAL Union
redefined the constellation boundaries in 1930,
the spiral galaxy NGC 2775 (Caldwell 48)
belonged to Hydra, not Cancer. It's quite
entertaining to compare today's seemingly rigid
and somewhat blocky constellation boundaries
with the looser, more curvaceous ones used in
the late 1800s. In fact, it's very much like comparing
the ragged boundaries of the eastern
United States with those boxy ones out west. It's
as if curves had suddenly fallen out of favor with
both celestial and terrestrial cartographers after
the turn of the 20th century.
On equinox 2000.0 star charts, NGC 2775 can
be found in the southeastern corner of Cancer,
just ½° north of the Hydra border. NGC 2775 is
the third most rewarding deep-sky object in
Cancer, especially for observers with small
telescopes; the other two are the famous Messier
open star clusters M44 and M67. The
The Caldwell Objects
round, very gradually very suddenly much brighter in the
middle, resolvable.
48
best way to locate NGC 2775 is to look 3¾° east
and slightly north of golden, 3rd-magnitude Zeta
(ζ) Hydrae. In some works that star is part of
Hydra's head; in others (this included), his neck.
The l0th-magnitude galaxy also lies only 1¾° due
east of an obvious binocular pair of 6th- and 7thmagnitude
stars that makes a near-equilateral
triangle with Zeta and another golden star, 5thmagnitude
Omega (ω) Hydrae. Since NGC 2775
is rather small and moderately dim, you must
star-hop slowly and carefully. The galaxy is just
visible in 7x35 binoculars. Be sure you're relaxed
when looking, and try to avoid any neck strain;
otherwise, the galaxy will fade from view (if
indeed you glimpse it at all).
In photographs NGC 2775 has a misty or
curdled texture and almost appears featureless at
a glance. But faint details do shine through. Most
prominent are the galaxy's bright nucle-
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