Astronomy

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light is spread

thinly across nearly

half a degree. As a

result, its surface

brightness is very

low, just above

background. But persevere, and you’ll spot

it eventually.

Once you find M101, scrutinize it

closely. Under exceptional skies, an 8-inch

telescope reveals a subtle spiral pattern

within the exceedingly faint halo. The

brightest arm curves away

from the core to the north

and unfurls toward the east.

Be forewarned, however, that

with large, faint galaxies like M101, there is

no substitute for sky transparency. You’ll

have to wait for that special, once-a-season

clear night before M101 reluctantly shows

its true nature. And don’t be afraid to use

medium or even high-power eyepieces to

distinguish individual features.

NGC 2903, at 9th magnitude and span-

ning 13' by 7', is one of the brightest and

largest galaxies in the spring sky that

Messier and his contemporaries missed.

But don’t you miss it. You’ll find it just

1.5° south of Lambda (λ) Leonis. Even

10x binoculars will reveal its noticeably

oval disk and brighter central hub. Viewing

this spiral system through an 8- to

10-inch telescope begins to reveal a com-

plexity that remains hidden in smaller

apertures. Through the largest backyard

scopes, NGC 2903 shows

many knots and irregularities.

The brightest, cataloged sepa-

rately as NGC 2905, is about 1'

to the northeast of the core.

Next, we have the Leo Trio, made up of

M65, M66, and NGC 3628. All three

reside some 2.6° southeast of Chertan

[Theta (θ) Leonis] in Leo’s hind triangle.

Spiral galaxy M66 is the dominant mem-

ber, outshining its two neighbors. Its spiral

arms are rather faint, however, mostly

because of its narrow tilt from our vantage

point. Most telescopes show only the gal-

axy’s oval core, though 8-inch and larger

apertures add hints of bright and dark

patches throughout the galaxy’s

spiral arm halo.

M65, found in the same medium-power

field of view, appears longer, thinner, and a

little fainter than M66. Although also clas-

sified as a spiral galaxy, M65 appears even

more edge-on to our line of sight. Again,

Leo’s NGC 2903 is a
bright springtime
galaxy overlooked
by Charles Messier,
the famous deep-
sky compiler. It has
a bright disk and
pronounced central
hub. KEITH B. QUATTROCCHI

The “Leo Trio” —

M65 (top right), M66

(bottom right), and

NGC 3628 — is a

fascinating contrast

of three distinctly

different types of

galaxies. CHUCK KIMBALL

The Black Eye Galaxy

(M64) is famous for its

distinctive dark patch

lying near the galaxy’s

center. ADAM BLOCK/MOUNT

LEMMON SKYCENTER/UNIVERSITY

OF ARIZONA