The Jasper weekly courier. [volume] (Jasper, Ind.) 1858-1922, 1913-06-20
DlSrANCEA0F THE STARS.



of Measuring 1t.
With the exception of a hundred
stars at, most, We know nothing Of
The distances of the individual stars.
What is the cause of this state of ]
things? 1T is owing to the fact that
we have two eyes that we are en-
abled not only to perceive the d. :
rection in which external objects
are. situated, but to get an idea OF
their distance, to localize them In
space. But this power is rather linn
tied. For distances exceeding some
hundreds of yards it utterly fails.
The reason is that the distance be-
tween the eyes as compared with /
the distance to be evaluated be-
comes too small. instruments have
been devised by which the distance
between the eyes is, as it were, artl-
fcially increased. With a good in
strument of this sort distances of
several miles may be evaluated. For
still greater distances we may i'm
agine each eye replaced by photo
graphic plate Even this would be
quite sufficient for one of the heav-
enly bodies-viz, for the moon.
st one and the same moment let
photograph of the moon and the
surrounding stars be taken both at
the Cape observatory and at the
Royal observatory at Greenwich.
Placing The two photographs side by
side in the stereoscope, we shall
clearly see the moon changing in
space" and may evaluate its die
tance.
But for the sun and the nearest
planets, or next ncighbors III the
universe aiter tie moon, the diff
Guilty recommences.
The reason is that any available
distance on the earth, taken as eye
distance, is rather small for the
purpose. However, owing to IN
credible perseverance and skill OF
several obserge and by substitut-
ing the moSt refined measurement
for stereosc.p.c examination, as
tronor.cf. l.: q succeeded in over
connie tie d''i'rI:t Tor the sun.
think a. ,Yav sav hat at present
0 We llnow Is il. tai-c to within
U thousand is't II its amount
Known he s4's distance, we ge+
that of al re planets by a vel
known relstion existing between th'
planetary distances.
But now for the fixed stars
which must be hundreds of thou
sands Of times farther removed thar
the sun. There evidently can be n
question of any sufficient eye dis
lance on our earth. Meanwhile GU
success with the sun has provide
,, us with a new one distance, 24,0O
r. times greater than any possible ey
10 distance on the earth, for now tina
V. we know the distance at which tn
10 earth travels in its orbit around tn
Or sun we can take the diameter of II
ID orbit as our eye distance. Photo
III graphs taken at periods six month
a apart will represent the stelia
m world as seen from points the di'
e. lance between which is already be;
s. expressed in the time it would tax
ke light to traverse it. The time woul
@. be about sixteen minutes.
However, even this distance, in
nd mense as it is, is, on the whole, IL
ore adequate for obtaining a stere
We scopic view of the stars. 1t is on
or in quite exceptional cases that pm
IS tographs on a. large scale-that
obtained by the aid of big tel
scopes-show any stereoscopic
Il feet for Fixed stars. By accura
measurement of the photos we mi
Du- perhaps get somewhat beyond VIII
T nty we can attain by simple stereoscop
the inspection; but, as we said IN
ays ment ago, astronomers have not 81
; %G ceeded in this way in determlnn
pc pc the distance of more than a hu
Gus dred stars in all.-Scientilic Anne
With can. --
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