The Jasper weekly courier. [volume] (Jasper, Ind.) 1858-1922, 1911-08-04
DISTANCE or THE STARS.
How Astronomers Set About the Ta..
81 Measuring n.

r. f~~~~ff'3 ~
9 with the exception OF a hundred
3. ttars al most, we know nothing OF
( the distances % the individual stars
What Is the cause OF this state of
things? Ii Is owing 10 the fact that
weshave two ewes that we are en-
abied not only TO perceive the d.
rection IN which external objects
are situated, but 70 get an idea of
their distance. 20 localize them in
space. But this power is rather lin
ited. For distances exceeding some
hundreds of yards II utterly fails.
The reason Is that the distance be-
tween the eyes as compared with
the distance 10 be evaluatcd bc-
comes too small instruments have
been devised hv which the distance
between the ewes is. as it were. arti-
tcially increased With a good in
strument of this sort distances Of
seyetal mics may be cvaluated For
stall greater distances we NAV i'm
aglne each eve replaced By a photo
graphic plate. Even this would be
quite sufficient for one OF the heay-
enly bodies-yiz, for. the moon.
AZ one and the same moment let
a photograph Of the moon and tho
surrounding stars BE- taken both M
The Cane observatory and AZ the
ROYAL observatory at Greenwich
Placing the two photographs side By
side IN the stereoscope, we shall
clearly see the moon. Hanging il
space and may evaluate its dis
tance.
But for the sun and the nearest
planets, our next neighbors in the
universe after the moon. the diff
Guilty recommeneeS
The reason Is that anv available .
distance on the earth. taken as eve
distance, i rather small for the
purpose However. owing 10 IN o.
credible perseverance and skill Of -
several observers and BY substitut-
ng the most refined measurement
Tor stfreoscopic examination. as
ronomers have succeeded in over
.oming the difficulty for the sun. I'll
hlnk we may say that at present
Fe know It's distance to within a I'll
housandth part Of its amount \
moving the suns distance, we get
nat OF aiae planets BY q we'll
nown relaNN existing between tho
lanetary distances. iii
But now for the fixed stars
Inch must be hundreds Of thou
inds OF times farther removed than 4
&c sun There evidently can be no
aestlon Of any sufficient eve dis III
lnce on our earth. Meanwhile our
iccess with the sun has provided 1
with new one distance. $4,000 Ill
mes greater than any possible eve Il
stance on the earth. for now that iii
know the distance at which the iii
nth travels IN its orbit aroundthe IL
N We can take the diameter of itsf
bit as our eve distance. Photo ~
apis taken at periods SIX months iii
d4N Viii represent the stellar
Did rs seen from points the dis
nee between which Is already best
pressed IN the time il would take
ht'to traverse it. The time would
about sixteen minutes.
However. even this distance. i'm
nse as y isis, on the whole. in
aquate FOR obtaining a stereo-
PIC view Of the stars. II is only
quite exceptional cases that pho
Taphs on large scale-that IS
AIMED by the aid OF bic tele-
any stereoscopie ef-
for fixed stars. BY accurate
..surement Of the photos we NAV
haps get somewhat beyond what
can attain BY simple steeoscopic
'ectlon; but, as we said a mo-
u ago, astronomers have not sue
led IN tins way IN determining
distance Of more than a hun
stars IN all.-Scientifc Ameri-