Harrisburg telegraph. [volume] (Harrisburg, Pa.) 1879-1948, 1919-12-05
Scientific Discussions
by Garrett P. Serviss

Every little while 1 receive a letter
about the movement of the sun. an
astronomical fact which seem to cause
Some think it means that the sun is
revolving around the earth. as the an
clients supposed that it did: others in
quire how it is possible that the sun
can move without leaving the planets,
or, If they go along. how it happens
that they all have exactly the same
speed and do not lag behind. and fall
into disorder; and still others ask
whether the motion is circular around
a distant center somewhere among
the stars, or is in straight or a zig
gag line. And a few think it is i'm
possible. that the sun can move at all.
The facts are these: The sun is
moving at speed of about IL miles
per second, which carries it about
one million miles per day, in north
sky which is not very far from one
of the most beautiful stars in the vis-
ible universe. the brilliant Vega, sit
uated in the constellation known
the motion is not directly toward that
great star. and it is not to be suppos-
ed that the attraction of the star has
any perceptible influence on the di-
rection, or speed. of the suns move
ments.
In truth, owing to the extreme diff
ficulty of determining with eXactness
either the speed or the direction, diff
somewhat different locations for the
apex" of the suns way" i. e.. the
precise point toward which its motion
is carrying it. The difficulty arises
from the fact that not only the sun
but all the other stars, it's brother
suns, are in motion, each with We
locity, and in a direction, of its own.
Thus il appears that flying through
space, one way or another. and often
with astonishing velocity. amounting
in some cases to several hundred
miles per second, is as natural and as
universal an attribute of suns as is
their radiation of light. Not one of
them stands fast, or could stand fast,
any more than the particles consti-
tuting a mass OF gas coulo remain
This indicates the ground on which
it has been assumed that the universe
of stars (suns) resembles widely
senting the vibrating gaseous mole
cules. This imaginary resemblance
may at least be used TO Illustrate the
unquestionable fact that the motion
of our sun is not something peculiar
to it, but something shared in differ
ing degrees, by every shining particle
of the vast organism called the uni
verse. II we regard the sun as SIMPLY
one of the flying molecules or atoms
of the starry universe, then, as far as
magnitude is concerned, we may con-
slider the earth and the other members
OF the solar system to be the corpu-
scles or electrons revolving around
the nucleus of that atom and sharing
it's movement as it swings to and fro,
or around and about among its num-
dreds of millions of fellow atoms.
The Illustration must not. however,
be pushed too far. The stars are not
arranged as regularly as are the par
ticles of mass of gas. They are. re-
.latively speaking, packed in some
places and along some planes and
thinIy scattered elsewhere. The plane
of the Milky Way is occupied by enor-
nous clouds Of stars; while the hemi-
paratively barren. But in those hemi-
spheres are compact star clusters,
denser than any part of the Milky
seem to be drawing in toward the
Milky Way, where. apparently, they
are destined to undergo scattering
process which will break up their
present com2SsGt 9rgannat6Se frnm t6e nresert
appearance of certain diffuse assem-
biages of stars in and near the plane
of the Milky Way whose motions sug-
pest that they came from outside Of
r and have undergone a scattering
since thew entered or passed through
it Our sun is involved in one of
these scattered cluster clusters 10 or = i'm the re-
THAT the planets accompany the
sun in it's movement among its fell
low suns is an inevitable result of
their connection with it in a gravita-
tional system. Their individual mo=
tions among themselves and around
the' sun are not affected by the COM
mon movement any more than are the
motions of the passengers inside
raiiway car. AS to the actual shape
81 the SUMS path through space moth
ing certain is known. AS far as obser-
vafions go it seems to be straight.
hut in fact 1t is undoubtedly an i'm
,oapso curve which may be more or
less Irregular and may or may not