Deep-Sky Companions: The Caldwell Objects

Описание

years of thought and observation arising from the
simple yet profound revelation that there's more
to observe in the night sky than the Messier
objects.
When Sky & Telescope introduced the
Caldwell Catalog in its December 1995 issue, I
had just completed the manuscript for Deep-Sky
Companions: The Messier Objects, my own first
foray away from the planets and into the
fascinating realm of the deep sky. I suppose, like
Moore, I too am hard to pigeonhole as an
observer. But that's really nothing new. Two of
history's most revered "deep-sky observers" were,
well, solar-system observers. Messier was an
experienced lunar and solar observer and, of
course, a comet aficionado. In fact, Messier was
not at all interested in the deep sky; the objects
we now admire in his list were nothing but
celestial mosquitoes to him — pests. And, as
Larry Mitchell, a member of the Houston
Astronomical Society, explains in his biography
of William Herschel (Appendix C), Herschel was
a "prolific observer of everything in the heavens."
Herschel was fascinated by transient phenomena
on the Moon, the polar caps and "luminous spots"
of Mars, Saturn's rings, and the belts and
flattened poles of Jupiter. It was Herschel, that
great deep-sky observer, who discovered the
planet Uranus, one of its moons, and two moons
of Saturn. Herschel also cataloged double stars,
tracked variable stars, and investigated stellar
distances. So Moore and I are simply a part of an
extended family of observers, a melting pot of
people who love to look at all manner of
heavenly wonders. What we like to observe is
merely a reflection of what soothes our hearts
and inflames our souls. (Besides, what you
observe is not nearly as important as how you
observe.)
Since the Caldwell Catalog was advertised
as a list of 109 objects "beyond Messier," it
seemed a natural candidate for the second
book in my Deep-Sky Companions series. As soon
as the Messier manuscript was mailed, I grabbed
my 4-inch Tele Vue Genesis refractor and began
another long but exhilarating visual journey
across the night sky. Soon I learned that some
observers believed the words "beyond Messier"
were shorthand for "Here's a list of incredible
deep-sky objects missed by Messier." Neither
Moore nor Sky & Telescope ever intended to
promote that view. A quick scan of the catalog's
contents, which include irregular dwarf galaxies,
prodigious sources of cosmic radio waves, and
dim bubbles of gas blown off of Wolf-Rayet stars,
proves otherwise, as does the simple fact that
more than half of the Caldwell objects lie south of
the celestial equator. In fact, I hope no one ever
publishes a catalog of objects "missed" by
Messier, because that would be a grave injustice
to the famed ferret of comets. As I explain in
Deep-Sky Companions: The Messier Objects, Charles
Messier was first and foremost a comet hunter.
His primary goal was to discover comets, not
deep-sky objects. He did not systematically
survey the night sky to discover every nebula
and cluster in it, as did William Herschel. Messier
explains as much in the Connaissance des Temps
for 1801: "After me, the celebrated Herschel
published a catalog of 2,000 [nebulae] which he
has observed. This unveiling of the sky, made
with instruments of great aperture, does not help
in a perusal of the sky for faint comets. Thus my
objective] is different from his, as I only need
nebulae visible in a telescope of two feet [in
length]." To fault Messier for excluding objects he
would never have confused with comets — or
that were beyond the visible limit of his modest
telescopes — would be like faulting treasure
hunters for not listing the names of birds hopping
around the piles of gold and diamonds they
discover. No, the Caldwell Catalog is a list
x The Deep-Sky Companions: The Caldwell Objects

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