The Douglas independent. [volume] (Roseburg, Or.) 187?-1885, 1879-09-06
Star showers.

Star showers.
Meteoric astronomy now takes rank as
a distinctive branch of astronomical sci
ence. Not forty years have elapsed since
periodical. Even them and for many
years after it was supposed there were bnt
two, called the August and November
showers. Now, not less than 100 have
been detected, and constantly others are
being added to the list. Tie accounts of
the showers that occurred i'll ancient
times came down to as clothed such In ex-
travagant language that, until the great
star shower of November 13, 1883, astrono-
mers were loath to believe them. Now
they know not only the cause, but are
able to predict their reoccurrence with
almost as much exactness as eclipses, and
the popular mind observes these displays
with equaninity and delight instead OF
fear and alarm, or thinking the day OF
judgment has come. Science has dis
armed not only them but eclipses and
comets as WE'LL of their terrors.
ALI know what shooting star looks
like, but no living man can tell what it
really is, for not one has ever been known
to reach the earth. Those heavy, stony
and still more weighty metallic masses,
called meteorlites, meteoric stones, etc.,
which occasionally fall to the earth from
the celestial regions, which the one that
recently fell in Iowa was q remarkable
example, belong to another class of objects
entirely, the origin of which man knows
| nothing.
A shooting star is only visible while
undergoing the process of combustion,
| which lasts from one to three seconds,
seldom longer. Previous TO this they ex-
ist in the dark, probably solid condition,
not much if any larger than peas, too
small to be seen in daylight and in the
night, being in the eartR's shadow, are
| eclipsed and consequently visible. Only
while being burned they are visible to US,
as they shine by their own light
Each meteoroid moves in an orbid, re-
volving around the sun with as much
regularity as the larger planets. In fact,
each is in every sense of the word q
| planet, obeying strictly the laws of gravi-
tation and planetary motion. All space
is filed with them they are as numerous
| as the sand. The earth and they in their
| journey around the sun encounter each
other; the earth, by its attraction, draws
them toward it, but to reach it they must
pass through the atmosphere, which one
is not liable to do Only meteoric stones
| are able to reach the earth, and they has e
! their surfaces blackened, and converted
to scoria by their terrible heat engender-
ed by the friction with the atmosphere
and by arrested motion.
Shooting stars move in all directions,
velocities probably equal to the earth's,
| nearly 10 miles second. One moving
retrograde, therefore from east to west),
would plunge into the atmosphere at a
relative velocity of 80 miles second
and if allowance be made for accelerated
motion, caused by the earth's attraction
probably double that. or rs miles a
second. The encounter is fearful, and but
for the atmosphere, which acts as
cushion, the effect would be disastrous
for not less than 100000 would rain upon
upon the earth every day.
The source from which these meteoroids
come is comets, especially from their tails
The tail of the great comet in 1911 was
l50, 100000 in length and 100000 ir
diameter. 1t is improbable in the highest
degree that the comet could gather its
tail to itself again. 1t is left behind
forming o ring, which in time may be-
come continuous. Another comet comes
and it does the same, and during the ages
which are past this process has been go
ing on till the inter-planetary spaces are
filled with not only meteoroids, but some
| tllng Sllll more marvellous.
In about three thousand years thai
great comet will return again and repeat
the process, forming part of another ring
or, adding to the first, depending on cir,
cumstances which need not be considered
here. Whenever the earth, in its usua
journey. passes through any ring made
by some comet, no man knews when We
get star shower. The four most notable
ones in our times take place at the fol
lowing dates, namely, on the mornings o.
August 18th and November 14th, and the
evenings of November Oath and 9th. The
last two are caused by the earth passing
through the track of meteoroids left be
hind by the fragments of Bida's coment
which divided in two parts in 1916. Ii
this way meteoric rings are formed, o
J which the solar system is filled, but none
are Visible to US, except those the eartl
was the August ring formed, which the
earth passed diagonally through on tht
! evening of the 10th and morning of The
14th of the present month.
The first August shower mentioned in
history occurred on July 25th, A, D., Sll
and has appeared with nnfailing regu
larity down to our own time, except {
slight break of SO years between S4l and
1924, and another and much greater one o.
$40 years between 933 and l243, owing
probably to breaks in the ring, or which
is more likely, to failure to record them
| The period of the above comet is about
l23 years, and it will therefore make it,
next appearance about the year 1885.
The eccentricity of the August ring il
very great, its perihilion distance being
equal to that of the earth, and its aphelior
distance being far beyond the orbit o.
Neptune, making the circumference o
the ring more than 1000, 100000 miles
and as the earth is ten Gays in passing
through 1t, its thickness must be at least
100000 miles.-Dr. Lewis Swit IN Roch
ister Erpress.