Semi-weekly south Kentuckian. [volume] (Hopkinsville, Ky.) 1883-1889, 1886-09-28
THE SUMS DISTANCE.
Great Difference In the Calculations
Xnrlous Astronomers.

Great Dt1erence III Inb Odicuibtiohh y
Various Astronomers.
The grand views of magn'tudos which
arise in connection with the considera-
ton of the physical condition of the
sun are, US matter of course, all de-
pendent upon the measures that have
been made of its distance. Because tho
solar sphere has the apparent size OF a
ono foot ball held 109 feet away, ii must
therefore be about 100000 miles across
if it be l0S times 100000 or 93,0OO,OOO
miles away; that is in, familiar form,
the rationale OF the process by when
the idea of its magnitude has been ac-
ouircd. Miss Clerke relates very fully
and charmingly the history OF the labors
which have been devoted by scientific
men 10 attain exact accuracy in this
Fundamental particular. So much the
greater pains have been taken in the
matter b ,cause the distance of the sun
is unayoidably the unit of the measure
TO be employed in making all further
investigations as to the profundlty OF
space. The semidiameter of the earth 5
sphere is necessarily the fundamental
unit in astronomical scrycys; and any
error in its determination is multiplied
in an inlinity of ways in all further con-
siderat.on of the planetary and stellar
distances. But the measure which has
to be accompl shed in coming to the
solution of this problem in the most
direct way is about the same tn ng rs
taking the apparent size of Il half penny
when held 1000 feet from the eye.
This is the amount which is known ms
the horizontal parallax OF the sun, that
is. the difference of the position which
the sun holds in the vast field OF space
among the stars according as it is
viewed from one or the other extremity
of the half diameter of the earth. The
transits Of Venus have been employed
as indirect means of getting at this
measure through the intervening stages
of mathematical calculations, SINCE the
first introduction of the method by
Horrocks in 1881. During the las
two transits of Venus-those, namely
which occurred in 1874 and lSS2-th'
most strenuous efforts by the astrono
mers of all civilized nations were t.
: get ms exact measure as was possible
In 1874 eighty distinct stations, scat
: tered over the most suitable portions
of the earth, wore established ut an eX
penditure of nearly quarter of n mil
: lion of money But the result is tina
, this method, so long cherished as tn,
t favorite of astronomers, is now founI
to have failed them. 1t is UNIVERSAL,
admitted by all that the sun is consider
, ably nearer to the earth than it wa
conceived to be a few years since. But
. so far as Transit observations are con
: cerncd, Mr.. Stone gives 92,566,OO
: miles as the corrected distance derives
p from the observations of 1874. NJ. Fay
rivcs 1866, COO miles; Prot Younl
90, Ss5, 900 and Dr. Ball $4,000, GOO
Doctors, therefore, disagree in this mat
ter very materially. From the transi
observations of 1882 the probable erro
was held by Prof Houzcuu, the lat
Director of the Brussels observatory
who devoted great LABOR and care to tn
| reduction and comparison Of the ca
K culations. to amount to 900, 900 eithC
: way, or to n total uncertainty OF 800
c OO6 N les BY common consent
c the best authorities the possible error
+ the measure of the suns iStanco
d this method of observing is held to
/ not less certainly than l 100000 milo
is -Edinbargh ReUieW.