Sky & Telescope - May 2024 - 55

Suburban Stargazer by Ken Hewitt-White
Hat Hunt
An attractive galaxy with an evocative name is well placed on spring evenings.
I
love galaxies. Big and bright, small
and faint - no matter, I enjoy observing
them. Even if the galaxy I'm scrutinizing
is dim and diffuse, my mind's
eye perceives an " island universe "
populated with billions of suns and
countless planets.
Alas, urban light pollution isn't
kind to faint fuzzies. Not many galaxies
are easily visible from my backyard,
and only a handful exhibit definable
features. My favorites are the slender,
edge-on types that exhibit a central
bulge and a bisecting dust lane. Several
top-tier edge-ons return every spring.
The brightest of the bunch is the Sombrero
Galaxy, M104.
M104 is dubbed the Sombrero Galaxy
because in telescopes it resembles
the iconic, broad-brimmed Mexican
hat - or does it? I'm deploying my citybased
gear to see if the Sombrero sobriquet
fits. For the project, I've chosen a
120-mm f/7.5 apochromatic refractor
and an 8-inch f/6 Newtonian reflector.
Getting There
I'm a star-hopper, so I study the location
of deep-sky targets very carefully.
M104 resides in southern Virgo, the
Maiden, almost right on the border
with Corvus, the Crow. My preferred
star-hop to M104 runs upward from
little Corvus rather than downward
through sprawling Virgo. The Crow
route is just 5.5° long and includes
bonus targets along the way.
Before I go any further, let me tearfully
describe my sorry suburban situation.
I live in a small, over-illuminated
Canadian city near the 49th parallel.
Because Corvus hangs roughly 20°
below the celestial equator, the cosmic
Crow flies low across the south. Worse, I
live on the north side of town. Corvus's
box-like pattern is barely visible inside
the light dome ballooning above my
south horizon. That dome of doom also
threatens the pale Sombrero.
My star-hop starting point is
3.0-magnitude Algorab, officially Delta
(δ) Corvi, which marks the northeastern
corner of the Corvus box. A fine
double, yellowish Delta harbors an
8.5-magnitude secondary sun 24.2″
to the southwest. The unequal set
looks best at around 50×. A short hop
northeast of Delta is 4.3-magnitude Eta
(η) Corvi. I can't see Eta directly, but it
shows readily in my finderscope. Good,
because I need Eta for my next move.
Using 8×50 finders, I shift the
pEDGE-ON ELEGANCE Slightly larger than our Milky Way Galaxy and only 28 million light-years
from Earth, the Sombrero Galaxy, M104, is strikingly elegant in this Hubble Space Telescope
image. Astronomers had considered M104 to be a tightly wound spiral galaxy exhibiting a large
bulge-to-disk ratio. However, the precise morphology was difficult to assess due to the Sombrero's
nearly edge-on orientation. The vast dust ring encloses the entire system. Although it's the 104th
entry in the popular Messier catalog of 110 celestial objects, the galaxy wasn't discovered by
Charles Messier - it was found in 1781 by fellow French observer Pierre Méchain. At the time,
Messier had completed his initial listing of 103 objects. Regardless, Messier noted Méchain's " faint
nebula, " and today it's designated as M104.
telescopes 3° north of Eta to a trio of
6th-magnitude stars outlining a handy
1°-long isosceles triangle. In my finder,
sweeping 1° northeastward - the
direction the triangle points - I find
a pair of 6.6- and 6.8-magnitude stars
5.5′ apart. Low magnification picks up
a 9.9-magnitude star a few arcminutes
north of the tandem, to create another
triangle. Nestled inside this triangle
is a tiny isosceles triangle. The base is
delineated by 7.9- and 8.3-magnitude
stars lined up north-south 28.1″ apart,
while the vertex is a 10.9-magnitude
flickering pinpoint 43.8″ eastward.
Altogether, this delightful trianglewithin-a-triangle
constitutes a multiple
called Struve (Σ) 1659. Σ1659 is
eye-catching in both scopes, though the
refractor needs about 100× to snare the
faintest pinpoint.
sk yand tele scope .o r g * MAY 2024 55
HUBBLE HERITAGE TEAM (AURA / STSCI / NASA)

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Sky & Telescope - May 2024

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