The Caldwell Objects

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NGC 3626
Type: Lenticular
Galaxy (SO)
Con: Leo
RA:11 h 20 m 04 s
Dec:+18° 21.4'
Mag: 11.0
Dim: 3.0' X 2.2'
SB: 12.5
Dist: 86 million light-years
Disc: William Herschel, 1784
W. HERSCHEL: [Observed 14 March 1784] Pretty bright,
small, a little extended, brighter in the middle. (Η II-52)
NGC 3626 is A CURIOUS OBJECT. AS IT IS ONLY
marginally visible in small telescopes, one might
wonder why Patrick Caldwell-Moore selected it
over the wealth of other galaxies in Leo; in fact,
NGC 3626 is the only Leo galaxy in his catalog.
Of course, the Caldwell Catalog is not intended
to be a list of 109 visually stunning objects but a
selection of Moore's favorite deep-sky objects,
whether they're telescopically dynamic,
astrophysically intriguing, or visually challenging.
The question, then, is how NGC 3626 fits
into the picture.
NGC 3626 is a tiny 3'-wide object that shines
with the light of an 11th-magnitude star. It is the
second-brightest member of a dense gathering of
10 galaxies (ranging in brightness from 10th to
about 13th magnitude) that populates Leo's
triangular hindquarters. All these galaxies are
plotted in the second edition of Sky Atlas 2000.0.
All but two of them (NGC 3691 and NGC 3599)
belong to the Leo Cloud of galaxies, an elongated
archipelago of ten dozen island universes. NGC
3626 is a classic lenticular galaxy whisking away
from us at
GC/NGC: Bright, small, very little extended, suddenly brighter
in the middle.
40
1,473 km per second. Less than 1° southwest of
NGC 3626 lies another lenticular galaxy, NGC
3607, which shines a full magnitude brighter than
our Caldwell target. (Why didn't Moore select
that one instead, I wonder?) NGC 3607 also is
part of a nice trio of galaxies, which is easy to
locate. Anyway you can use this grouping as a
steppingstone to NGC 3626.
To find NGC 3626 first locate the 3rd-magnitude
stars Zosma, or Delta (δ) Leonis, and
Chertan, or Theta (θ) Leonis, the westernmost
stars in the Lion's hindquarters. The aforementioned
trio is just east of the halfway point
between the two stars. If you set your finderscope's
cross hairs on the imaginary halfway
point and use a wide-field eyepiece in your main
telescope, the trio's brightest two galaxies (NGC
3607 and magnitude-10.8 NGC 3608) should be
quite obvious. The third trio member, 12thmagnitude
NGC 3605, will also be in the field, a
few arcminutes southwest of NGC 3607. In the 4inch
at 23x all three galaxies pop into view,
though NGC 3607 and 3608 are naturally more
readily visible than NGC 3605.
The Caldwell Objects 159