The Caldwell Objects

was more readily seen in binoculars and finders
than in telescopes. . . . [James] Meketa believes
that the Helix might be seen with the naked eye
under excellent conditions."
Today, large, low-contrast objects are the
bane of urban and suburban skywatchers.
Throughout my childhood, the Helix was one of
my visual nemeses. It was right up there with
M74, that large and diffuse galaxy in Pisces. I
grew up in Cambridge, Massachusetts, and did
most of my observing with either a 4½-inch longfocus
reflector or the 9-inch Clark refractor at
Harvard College Observatory. For 20 years I
searched for the Helix on the best nights, when
the object was high above the horizon, but I
had two strikes against me: city lights and a limited
field of view. I did not succeed in seeing the Helix
until July 27, 1997, after I started the Caldwell project
under the dark skies of Volcano, Hawaii. I did not
know what to expect at first, because until then I had
only viewed
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the Helix in photographs. So imagine my surprise
(and disgust) when I raised a pair of 7x35
binoculars to the field and saw the Helix without
a hitch! For the first time since childhood I felt a
sense of primal awe and astonishment. "It's
glorious," I penned. "It's enormous. And with
averted vision I suspect a hole." Because of this
shocking sighting, NGC 7293 became what I
called the most "surprising" object in the
Caldwell Catalog. It became even more so when I
also "suspected [having seen] it with the unaided
eye" that same night.
Given that provisional detection, I was
astonished to come across no positive naked-eye
sightings of the Helix in the literature. The closest
account I found was a statement by Hans
Vehrenberg in his Atlas of Deep-Sky Splendors.
There he writes that the Helix "is of such low
surface brightness that even on dark and
extremely clear nights it is barely distinguishable
as a very faint patch." Unfortunately, we do not
know if the sentence pertains to the telescopic or
naked-eye view. But once again I surprised
myself by finding support for my tentative
naked-eye detection in an unexpected place.
While researching an article on the gegenschein
for the May 2000 issue of Sky & Telescope, I came
across the following entry, dated October 3,1983,
in my Hawaiian diaries (I was only 26 years old
at the time): "The Helix Nebula was visible to the
unaided eye as a very faint almost imperceptible
haze." That night I was testing the naked-eye
limit of the night sky from a 4,000-foot-high site
in Waimea. I saw stars as faint as magnitude 8.0
and estimated the Helix's apparent magnitude to
be 6.0.1 did not even seem impressed that I did
this (remember that I was foremost a planet
observer then), nor did I bother looking at the
Helix with binoculars. The object just happened
to be in the field that I was watching. This
"discovery" also alerted me to the fact that
The Caldwell Objects 249