The Opelousas journal. [volume] (Opelousas, La.) 1868-1878, 1877-09-01
THE DUMB-BELL NBB ULA.


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In Vulpecula there is a remarkable
object called the Dumb-bell nebula, or
s~tar-cloud. 1t cannot be seen we'll
without a very powerful telescope. 1t
was formerly thought 10 consist entirely
of small stars, SO remote that they
could not be separately d%iscerned; but
it has lately been discovered that the
greater part of this nebula's light comes
from glowing gas. The vastness of the
space occupied by this cloud of luminous
gas will be understood-though no
mind a possibly conceive it when
I mention that at the distance of the
nearest of the fixed stars the whole of
u solar system would appear but as
a mere point, even in a powerful tele-
Scope. The Dumb-bell nebula overs
quite a large space as seen in such an
instrument. 1t is also, probably, much
farther away than the nearest fixed stars.
1t must, therefore, occupy a region OF
space exceeding many times that
through the planets of cur solar system
pursue their paths, Yet the span of our
earth's path around the SUI is tt}ly one
hundred and eighty-four millions of
miles, while Neptune-the remotest
planet of the solar system--travels
thirty times farther from the sun,
having thus al orbit spanning o
than five thousand millions of miles.
A globe just fitting the path of Nep"
tune would contain many quadrillions
of cubic miles'--and probably the
Dumb bell nebula exceeds such a globe
in volume Tor, to sneak more exactly,
occupies a space exceeding such a globe
in volume) many millions of times.
Very strange is the thought that as
tronomers should have been able to find
out what this mighty mass of glowing
gas consists of. Placed yonder amid the
glories of the milky way, lost to human
vision through its vast remoteness, only
brought within our view at all by means
of powerful telescopes, and only reveal
ing its true shape when seen with the
most powerful telescopes men have yet
constructed, what at first sight a seem
more amazing than that men should be
able to tell what kind of substance it il
which gives out the misty luster of that
cloudlet in space? The very light which
comes to us from the Dumb-bell nebu1a
has probably taken hundreds of years in
crossing the tremendous space separating
us from that object. Yet that light has
conveyed its message truly. Examined
with that instrument, the spectroscope
whose oz1ce I lately described in a pa,
per On the planet Venus,-the light o.
the Dumb-bell nebula presents, not the
rainbow-tinted streak which comes from
glowing solid and liquid bodies, but three
bright lights only. At least three lines
are seen if the nebula is examined
through a foe slit if the field of view il
opened, there are seen three faint images
of the cloudlet. The correct way Of
describing what the spectroscope tells uE
about this object is to say that, instead Of
It's light presenting all the colors of the
rainbow, it is found, when sifted by the
spectroscope, to contain three colors only
all of them greenish, but slightly different
in tint. One of the colors is precisely
such a tint of green as comes with fou1
other colors) from glowing hydrogen gas,
and shows us that there are enormous
masses of Hydrogen in that remote cloud
another tint shows, in like manner, that
there are immense masses of nitrogen
but the third tint has rot yet been found
to correspond with a tint emitted by any
known substance. The skein of light
from that double huf-ball has thus been
~unraveled by the spectroscope, after
journeying millions of millions of miles,
and has been sorted into three tints, two
Of which have been matched against the
known tints of earthly gases, but the
third remains s yet unmatched.--Prof
r. A. Proctor, st. Nicholas for august