 In
researching this little-known open cluster on the web I came across
the following description by Bill Ferris: "This guy definitely
scrapes the bottom of the deep-sky barrel." He further
claims that, "The Herschel 500 list is filled with boring,
little open star clusters. This is one of them."
I cannot agree with
this sentiment, and I'm saddened that someone of the stature of Mr.
Ferris would write such a thing about any object in the night sky.
After all, this sentiment
could be expressed about so many of the objects we observe.
Consider that even the most colorful describer of the Universe would
be hard-pressed to describe a quasar as visually interesting.
Yet for many of us, the idea of what we are seeing with our
own eyes more than makes up for any lack of visual impact. We
see the quasar not just as a point of light, appearing just like any
star in the field, but in our mind's eye as well.
So what do I see in NGC
381 that makes it interesting? I see a family of stars.
I see opportunities. In this cluster of stars lies the keys to
unraveling the history of this family and our galaxy in general.
A family of stars such as NGC 381 allows us to understand stellar
evolution, to map out the distribution of stars in our galaxy, and
to probe the gas and dust that lies between them and us.
These things can be
said about any open cluster of course. But for me personally,
my connection to this cluster goes somewhat deeper. When I
first came across NGC 381 it was little more than a row of numbers
in a catalog. As an undergrad astronomy student I was looking
for an observing project. NGC 381 seemed to fit what I was
looking for; it was well placed for observation in the fall and
poorly studied. In fact, one of the notes indicated that it
may not be a real cluster of stars at all. In my mind NGC 381
had transformed itself from a row of numbers to a question mark -- a
question mark that I became determined to answer.
The following fall I
began my first UBV observations and got my first look at NGC 381.
I saw it through an eyepiece of rather low quality attached to a
photometer on the 1 meter telescope at Mount Laguna Observatory
(near San Diego). The magnification was too high to see the
entire cluster, but as I worked my way through the stars in the
region several asterisms became my guideposts and they remain with
me to this day (decades later). Look for a small arrow-like
asterism on the south end of the cluster. To the north lies a
string of three bright stars just beyond the cluster's edge.
Joe Bergeron described these as "a string of stars trailing
north that makes it look like a balloon." NGC 381
appears on his list of favorite
obscure deep-sky objects. One of the questions I answered
with my study was that these stars are not members of the cluster.
And yes, NGC 381 is in fact a real cluster. It turned out to
be a family of stars born together 3000 light years away, some 300
million years ago. When this cluster was born the 9000 foot mountains
on which I live were a warm shallow sea teaming with life.
In a 6-inch this
cluster looks like a small, hazy patch. Larger telescopes will
begin to reveal the main body of stars. I recently revisited
my old friend NGC 381 with my 18-inch f/4.5 Dob. At 97x it
appeared as little more than a slight, round, concentration of stars
in a field that is already quite rich. At 250x it nearly
filled the field and the familiar asterisms became apparent.
The field in an 6-inch f/8 at
150x. North is down and east is to the right.
So, is NGC 381 boring?
That depends entirely on how you choose to look at it, and I don't
mean how large your telescope is or what magnification you employ.
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