The Pulaski citizen. [volume] (Pulaski, Tenn.) 1866-current, 1874-07-23
COMETARY.
A Little Popular Science About COggfa's
and Other Comets.

The second comet of 1874, in which
the popular interest Is daily deepening,
appears to have defied astronomic COM
putation till very recently. For some
weeks IN June it was approaching the
earth in so direct line that the calcu-
lations were very difficult. The Berlin
ephemeTis of its position, brilliancy and
future pathway, so freely published
last month, because so confidently trus-
ted In this country, proved to be decid-
edly fallacious in some points. In the
last few days the meteor has altered its
course and Is now more easily studied;
but very precise predictions are as yet
premature. 1t now appears that its
greatest brilliancy viii occur from July
81 to the Sd of August, and the degree
of luminosity viii be between that of
Jupiter and that of Venus. The nu-
cleus viii be then seen to the best adj
vantage about twilight, the comet being
so near the SIM that it will not be OBJ
served two or three hours after the lat
ter sinks behind the western horizon.
The brightness of the meteor stream
viii then be three times as great as it is
now.
On Tuesday, the 9th of June, from
micrometrical comparisons with star
in the Bonn catalogues, the distin-
guishad astronomer, J. r. Hind, of Mr..
Bishops observatory, Twickenhan, Eng
land, found that Coggia's comet was
then rather brighter than Argelander's
stars of the sixth magnitude, and the
tail was traceable about two degrees
from the nucleus, which still presented
very stellar appearance. Mr.. Hind
also determined that its perihelion pas
sage would take place on the 9Th of
.FnIU Vvhnr Tfu 1gS,
would be sixty-seven minutes of the
earth's mean distance. e., about six
ty-one million miles. This seems to be
very near the central orb of fire; but
there are instances of much nearer APP
proach, as IN the comet of 1860, which
swept within six hundred thousand
miles of the sun. It did not, however,
merge into the sun, as comets havenever
been known to do, contrary to a vague
theory that has been largely enter
tanned, as if the nebulous matter was
fuel for its mighty furnaces. So far
from this rash venturer upon the suns
domains efecting a Judgment on his in
candescent and tumultuous surface, it
was subjected to an enormous repuIsion,
and from the point of perihelion was
shot out into space with an ineoncCiva-
bic force, far greater than that with
which the solar heat acted upon and
controlled the head of the comet itself.
The amount of this force may be faint
ly indicated when we reflect that the
cometary matter was then glowing with
heat twenty-five Thousand six hun
dred times as intense as that which
RACES at MONDAY on our eouator-a
heat in which any terrestrial substance
known to us would instantly be CONVEX
ted into vapor.
The condition of a comet, after it has
passed the perihelion, must be very diff
ferent from what it was before but
that difference is yet to be ascertained,
except in the mere fact that from disun-
ion by action of heat the meteor has
undergone great attenuation and analy-
sis. The comet of 1880, to which we
have alluded, and that of 1913, after
their immersion in the suns rays emerg-
ed from them in augmented splendor
and with vastly enlarged tails, as if
they had caught up new supplies of
light and fire from the great luminary.
1t would not be, therefore, a great sur
prise Of OSggia's comet should do the
same, though instances are recorded in
which immersion in the solar rays has
stripped the flying meteor of much of
its glory. The idea has been expressed
that the present comet viii intersect the
earth's orbit and come in collision with
us. The opinion prevailed with Sir
John Herschel and others that if ever
the earth swallowed up a comet it would
be on the 30th of November, when
Biela's comet approached very near
But there is great doubt whether. in
the event Of actual collision, any harm
would ensue or even any one be cogni-
zant of it. The comet is a material
substance, since it has been proved that
it shines by reflected light but its
Nervousness is almost uncomfortable.
The cometic particles form a cosmical
fog or vapor so light that, through Do
MATHS comet, where the tail was ninety
thousand miles thick, the stars clearly
shone. Arcturus was in no degree
collapsed, as it beamed directly through
this enormous band of mist. We NAV.
therefore, safely dismiss the long stand
ing superstition Of
A painless comet and a curse
Themenance of the universe.
Various theories have been offered as
to the purpose for which comets were
created and sent flying about through
illimitable space. By some it is thought
they may be the scavengers of the uni
verse, sweeping up the impurities that
accumulate from the countless worlds
of an infinite creation. They have been
regularly appearing in our solar system
as long as astronomy can recOllect. and
! mayhap If they did not put in an an
pearanee at intervals some dreadful ex-
plosion of electricity might occur that
might blow our globe to pieces, Those
of religious turn will have it that they
come to remind man of his Contempt
bic helplessness, of the little account
he could possibly be IN the struggle
with the tail of comet, and to drive
the ruinous and sinful passions of pride,
avarice and ambition from his heart.
Again, there are those who believe that
comets may act as a balance wheel in
the vast machinery of the universe. No
serious thought can be given the notion
that comets are rebels who have de-
ciined to submit to established authori-
ty and broken loose from their alleQi-
ance. Nor will it do to contend that
they are sent around the universe to
inspect the condition of the regular old
stagers, such as we happen to have in
our solar system. Certain it is. thew
are the mystery of the skies, and when
we think We know most we know per-
haps least about them.
Sir Isaac Newton gave some attention
to the subject, and the conclusion he
reached was that the course of a comet
was rs regular as the course OF our own
planet. He contended that the orbit of
the comet was an eclipse. but since his
day the idea appears to be taking pos
session of the minds of astronomers
that the comet describes an eccentric
parabola so int icate as to battle caIcu-
lation. Many comets have come and
gone and have never been heard of
since, though, according TO astronomi-
cal calculations, they should have turn
ed up long since and Obliged the obser-
vatories. Donati's comet was said to
have visited this earth about 5000
years before its discovery by Donati.
and that il would come 8, 900 wears
hencs on another visit, when Donati and
all of us are dead and buried. It is
clear that astronomy has not yet reached
that perfection of calculation which can
furnish the precise travels of comet. I
If comet comes FROM the depth of
space, as it has been said, and returns
thereto, the journey is not ended. She
must keep forever on the move to fulhll
her evident DESTINY and sha cannot