Yorkville enquirer. [volume] (Yorkville, S.C.) 1855-2006, 1912-06-04

lrange of the earth's 'orbital motion"
This method of measuring the dis
ltance Of the fixed stars Is called the
annual parallaxes. Proctor tells us in
I"Other Worlds Than Ours" that we
can actually see with the unaided eye
$3.50 stars. or this vast number only
a few seem to change even slightly
the earth in its orbit
Prof. T. I. l. See, one Of the great
est, If not the very greatest Of present
day astronomers, says: Some $50
stars have now been studied by the
standard method of parallaxes and
for most of these, perhaps about 200
in number, fairly satisfactory data
have been deduced; but the method
can be extended only to within less
than 100 light years Of our sun, and
Is therefore very limited in its appli-
cability, owing to the small diameter
Of the earth's orbit, and the insensi-
BILE effects Of the annual displacements
resulting from the orbital motion Of
/ our aS hdtui hSiSCll lldo iSN
ed the limits Of this method, astron-
omers have naturally cast about for
other methods of greater generality
and have finally developed processes
of surprising power"
The above quotation is from DR..
Sees paper, entitled Determination
of the Depth of the Milky Way" pub
lished in January Of this year in the
proceedings Of the American Philo-
sophical society held at Philadelphia
for promoting useful knowledge"
The light-year Is a term used by as
tronomers In estimating unthinkable
distances in the starry heavens. Light
has a velocity Of 10000 miles per
second. The light-year is the distance
which light traverses in one year of
our time. The nearest fixed star, AL
lpha Centauri, Is removed from us
distance Of three and one-half light
years. Multiply the number Of sec
onds in a year by 10000 and you
have the number of miles to the near
est fixed star. OF course, everybody
knows that the fixed stars are beyond
the limits of our solar system. Our
solar system consists Of the sun. moon
and planets, and these are close to-
gether, comparatively speaking. Light
travels from the sun to the earth in
trife over eight seconds.
Prof. See has for years made care
full Investigations into double stars.
By combining the Sir William Her
schel method of gauging ar-distances
with the modern spectroscope pro-
cess and applying his improved
method to double stars Prof. See was
enabled to find paralIaxes Of systems
very remote from the earth. He says
in the paper above quoted:
| I'm 1890, while a postgraduate stu
dent at the University Of Berlin, I de-
veloped this method still further, and
showed how 1t could be used also to
test the accuracy Of the law Of graVi-
tation in the stellar systems. The
spectroscope method then outlined
was brought to more general form In
I1S95, and 1t at once occurred to me to
point out its use for measuring the
distance of clusters in the Milky Way
as more certain than Herschel's meth
cd of star gauges. On looking more
closely in the spectroscopic method,
which in 1895 had been shown to be
applicable to objects 1000 light years
from the sun, and might thus include
all suitable double stars within this
sphere. I became convinced that,
while it is a great theoretic advance
over the old method Of parallaxes, 1t
is still quite inadequate for finding the
distances of the most remote objects
in the sidereal universe. Accordingly
in 1909 I returned to the improvement
of Herschels method as the most
remote objects.
| "The most remote stars are separ-
ated from us by distance Of at least
1000, 900 light-years, and as this space
Is a thousand times that to which the
spectroscopic method may be applied
/ it follows that there is no way Of faith
oming these immense distances, ex-
lcept by the improvement of the meth
cd Of Herschel.
| Prof. See spent some years at the
Lowell observatory, near the city OF
Mexico, and had the use Of the new
twenty -four-inch refractor. He en-
ployed every means for determining
the depth of the Milky Way. One OF
these means Is the use of photography.
The Photographic instrument Is at
tached to the telescope, which moves
of course, exactly with the revolu-
ton Of the earth. Hence the sensitive
Photographic plate Is exposed for
hours, thus picking minute stars and
clusters of stars which are totally in
visible through the telescope. This
process has revealed many wonders OF
the starry depths. The unaided eye
can detect a star of the fifth magni-
tude-a keen eye may see star of the
sixth magnitude. One astronomer,
Prof. w. S. Adams, using the system
of Photographic magnitudes Of the
Harvard college observatory, has sue
ceeded in taking stars Of the twenty
| first magnitude. Prof. See asserts
that the depth Of the Milky Way de-
cidedly exceeds one million light
years. He adds:
with our greatest modern instru-
ments and the use of photography 1t
is certain that we can observe stars at
a distance Of over two million light
years, and it is very probable that we
can penetrate to a depth Of about five
million light-years. At the present
time a twelve-foot reflector Is possible,
and the depth to which we can pene-
trate is simply question of telescop-
ic power, which can be vastly but not
indefinitely increased. An6 this is
true in spite Of the extinction Of light
by cOsmic dust in space. There Is
limit to the distance to which any
telescope can penetrate, but 1t In
creases steadily with the aperture,
since the only question involved Is one