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The Caldwell Objects

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was more readily seen in binoculars and finders<br />

than in telescopes. . . . [James] Meketa believes<br />

that the Helix might be seen with the naked eye<br />

under excellent conditions."<br />

Today, large, low-contrast objects are the<br />

bane of urban and suburban skywatchers.<br />

Throughout my childhood, the Helix was one of<br />

my visual nemeses. It was right up there with<br />

M74, that large and diffuse galaxy in Pisces. I<br />

grew up in Cambridge, Massachusetts, and did<br />

most of my observing with either a 4½-inch longfocus<br />

reflector or the 9-inch Clark refractor at<br />

Harvard College Observatory. For 20 years I<br />

searched for the Helix on the best nights, when<br />

the object was high above the horizon, but I<br />

had two strikes against me: city lights and a limited<br />

field of view. I did not succeed in seeing the Helix<br />

until July 27, 1997, after I started the <strong>Caldwell</strong> project<br />

under the dark skies of Volcano, Hawaii. I did not<br />

know what to expect at first, because until then I had<br />

only viewed<br />

63<br />

the Helix in photographs. So imagine my surprise<br />

(and disgust) when I raised a pair of 7x35<br />

binoculars to the field and saw the Helix without<br />

a hitch! For the first time since childhood I felt a<br />

sense of primal awe and astonishment. "It's<br />

glorious," I penned. "It's enormous. And with<br />

averted vision I suspect a hole." Because of this<br />

shocking sighting, NGC 7293 became what I<br />

called the most "surprising" object in the<br />

<strong>Caldwell</strong> Catalog. It became even more so when I<br />

also "suspected [having seen] it with the unaided<br />

eye" that same night.<br />

Given that provisional detection, I was<br />

astonished to come across no positive naked-eye<br />

sightings of the Helix in the literature. <strong>The</strong> closest<br />

account I found was a statement by Hans<br />

Vehrenberg in his Atlas of Deep-Sky Splendors.<br />

<strong>The</strong>re he writes that the Helix "is of such low<br />

surface brightness that even on dark and<br />

extremely clear nights it is barely distinguishable<br />

as a very faint patch." Unfortunately, we do not<br />

know if the sentence pertains to the telescopic or<br />

naked-eye view. But once again I surprised<br />

myself by finding support for my tentative<br />

naked-eye detection in an unexpected place.<br />

While researching an article on the gegenschein<br />

for the May 2000 issue of Sky & Telescope, I came<br />

across the following entry, dated October 3,1983,<br />

in my Hawaiian diaries (I was only 26 years old<br />

at the time): "<strong>The</strong> Helix Nebula was visible to the<br />

unaided eye as a very faint almost imperceptible<br />

haze." That night I was testing the naked-eye<br />

limit of the night sky from a 4,000-foot-high site<br />

in Waimea. I saw stars as faint as magnitude 8.0<br />

and estimated the Helix's apparent magnitude to<br />

be 6.0.1 did not even seem impressed that I did<br />

this (remember that I was foremost a planet<br />

observer then), nor did I bother looking at the<br />

Helix with binoculars. <strong>The</strong> object just happened<br />

to be in the field that I was watching. This<br />

"discovery" also alerted me to the fact that<br />

<strong>The</strong> <strong>Caldwell</strong> <strong>Objects</strong> 249

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