Astronomy

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is a remarkable example of a spiral system. In images,
it looks like a spinning saw blade whisking toward
the observer at a skewed angle. From Hawaii, I have
spied it with 7x50 binoculars. The 10'-long oval glow
displays a fuzzy core (with a starlike nucleus), from
which feathery extensions give way to a strong spiral
arm to the northwest and a weaker one to the south-
east. Larger scopes may be able to make out its prom-
inent star-forming regions and dust lanes.
Return to the wishbone and seek out the magni-
tude 6.5 star 17 Comae Berenices, a strikingly wide
double star marking the wishbone’s southeastern tip.
Only ½ ̊ to its southeast you’ll find another remark-
able 10th-magnitude galaxy: NGC 4494, a highly
condensed elliptical system appearing as a 2'-wide
cometlike glow with a diffuse core and bright central
condensation. We are now within striking distance of
the gem in Berenice’s Hair.
NGC 4565 — the most popular edge-on spiral
galaxy in the night sky — lies but 1 ̊ east-northeast of
NGC 4494. While the galaxy shines conspicuously at
magnitude 9.5, it is wafer thin, spanning 16' in
length, but only 2.5' in width. Years ago, I watched in
awe as the galaxy drifted from tip to tip through a
16-inch Boller & Chivens Cassegrain telescope at
Oak Ridge Station in Harvard, Massachusetts. Of
that experience, I wrote: “Suddenly the sharp tip of a

blade of light entered the field from the upper left.

Deeper and deeper it cut into the field of view, until

the galaxy’s robust hub and girdle of darkness all but

shattered the visual serenity that had preceded its

appearance. I continued to slew the telescope, but the

galaxy did not end — not until its leading edge began

to exit the opposite edge of the field of view.”

While some observers tend to stop at NGC 4565

and go no further, do push on, because 3 ̊ to the east-

southeast you’ll find one of the constellation’s hidden

treasures: magnitude 9.5 NGC 4725. This supergiant

spiral has only one arm, which originates from a

youthful inner ring rife with young blue stars and red

star-forming regions; that ring is, in fact, the most

complete spiral ring of any galaxy known. The single

The bright spiral

galaxy NGC 4559

appears like a spinning

saw blade hovering in the

sky. JEFF HAPEMAN/ADAM BLOCK/

NOAO/AURA/NSF

The bright double

star 24 Comae

Berenices consists of an

incredible color contrast:

The golden primary

star shines beside a

slightly fainter sea-green

companion. The artist

sketched this pair with

a 6-inch f/8 reflector at

240x. JEREMY PEREZ

The most

popular edge-on

galaxy in the

sky, NGC 4565

is wafer thin,

spanning 16'

in length, but

only 2.5'

in width.