The Jasper weekly courier. [volume] (Jasper, Ind.) 1858-1922, 1917-11-02
NSIMcE sOF THE STARS


tsc~ Astrsnoms~s Set About ths rssA
CT Measuring 1t
Withsthe exception of . hundred
stars atsmost, We know nothing Of
Tho distnces Of the individual stars.
Whsksis the eause Of this state Of
thingaf 1t is osing 10 the fsct that
We have two eyes that we are en-
abled net only TO perceive the di-
rection In which external objects
are situated, but 70 get an idea Of
their distance, to localizs them IN
space. But this power is rather linn
tied. For distances exceeding some
hundreds of yards IL utterly fails.
The reason Is that the distance be-
tween the eyes as compared With
the distance to be svalnAted ~
comes too small. instruments hare
been devised BY which the 6sta,cs
betwan the syes i, ~ Il wers, asti-
fcialJ iacrs.s~ With q god In
strumAat q tAHssort distances a
several nla ~ ybs evaluated. Tor
still greater distances We may I'm
agine each eye ssplsced BY photo
graphic plate. Even this would b
quite sufficient FOR one Of the heav-
enly bodies-vix, for the moon.
At one and the same moment let
q photograph Of the moon and the
surrounding stars be taken both at
the Cape observatory and at tho
Royal observatory at Greenwich.
Placing the two photographs side by
side in the stereoscope, we shall
clearly see the moon hanging In
space" and may evaluate its dis
tanoe.
But for the sun and the nearest
planets, our next neighbors IN the
universe alter the moon, the difn-
Guilty recommences.
The reason il that any availshs
distance on the earth, taken 90 eye
distance, is rather small for The
purpose. However. owing 70 IN
credible perseverance, and skill OF
several observers and by substitut-
ing Che most refined measurement
for ssersoscopio examination, ss-
truuomsrs have succeeded in over.
coming tho difficulty for the sun I
think we nay say that st present
We know its distanes - within .
tho~ san5tn part Of IL smeunt
Knowing the suns distance, We gst
thnt Of all the planets BY . veil
known reis ion existing between The
planetary distances.
But now for tho fixed star.
which must be hundreds Of thou
sands of times farther removed than
the sun. There evidently can Re No
question of any sufficient eye dis
tance on our earth. Meanwhile suS
success with the sun has provided
ue with o new one distance, $4,000
times greater than anv possible eye
distance Oh the earth, for now that
we know the distance at which the
earth travels in its orbit around tho
srn we can take the diameter of its
orbit as our eye distance Photo
graphs taken at periods six months
apart will represent the stellar
world as seen from points the dis
t,raa between which is already best
e1Dressed in the time it would take
,ight to traverse it. The time would
be about sixteen minutes.
However, even this distance, i'm
mense as it is, is, on the whole, In
adequate for obtaining a stereo-
scopic view of the stars. It is only
in quite exceptional cases that pho
tographs on a large scale-that il,
obtained by the aid Of big tele-
scopes-show any stereoscopic ef-
feet for fixed stars. By accurate
measurement Of the photos We may
perhaps get somewhat beyond what
we can attain by simple stereoscopic
inspection; but, as We said Q mo-
ment ago, astronomers have not sue
ceeded in this way in determining
the distance of more than . hun
dred stars In aU,-Scientfc AmuS
can. kxS~~