Milford chronicle. [volume] (Milford, Del.) 1878-1974, 1891-09-11
lnrEapLANsT SIGNALING.

p.r.on who Shall Find Way.
A French nun has bequeathed 10000
$780, ~ the Academy OF Science, to be
given "A a prize to any one who shall aus /
cover any means Of communicating Win
another world, planet or star, The pianei
Mars was suggested In the will as the most
convenient heavenly body on which u
make the experiment..
iaTbis nropositlon may seem ridiculous,
hut Il Is not any more so than the ldea o.
James Lick, the founder OF the LACK %
servatory, said man well vefsed In starr5
'aThe Lick bequest to bald the great
telescope was intended to establish 1ns
fact whether or not the moon Is lnhaoiv -,
Now let US consider the diihculties ~ ~ ~
way Of this project The distance OF 'ns
earth from the moon may De stseea ~
round numbers as 24O OOOmiles ~ = q ~.
reco0nized in military science that mar
csn IL fairly distinguished by the eye at
n,Ilala distance. In making calculations
regarding vision it is the general rule e
eatinate that to be seen a mile away an Cd
isct u,nst be half a yard wide. The Desi
telescope has q magnifying power OF S'OW
diameters. 900 m,
isHalfthe distance to the moon Is lSO,ON
miles Divide this by 1000, the magnify
inc power Of the glass; and you get Sky
Yards as the minimum size OF an object ID
tbe moon discernible by the aid Of the tele
seope from the earth. So an object must
| ~ isO feet wide or thick to be more than
an annreciable dot have made the most
liberal allowances in this computation
The atmospheric condition must be per
feet. and 2 900 is an unusually high power
TO be used by an astronomer.
AFT an object must be $50 feet thick 70 b,
/ seen from the earth on the moon, II wouio
be best to make it 200 feet TO give tns
| inhabitants Of the moon an IDEA thht tners
are intelligent beings on earth' It would %
necessary to place, say, three objects IL
view OF the moons people-iet them re
4 main for time arranged at the angles o.
| ! trian0le. Then they might be changed
| 40 as to be in a straight line. The man N
the moon. seeing these phenomena, might
conclude that there were intelligent beings
on earth and arrange for some correspond
ing signal to the inhabitants OF earth. But
while this seems possible, It shows no"
preposterous would be the attempt to de
| termine with the most powerful telescope
now in use whether the moon Is inhabited
'tNow. as to the proposed communication
| with Mars At the time when Mars ano
the earth are nearest to eadA other-are ID
perihelion-the distance is in round mum
| hers q. GOO 600 miles. Take half this dis
tance and YOU have II 100000 as the mum
her OF wards that represents the size OF al
object IN Mars that could be seen that dis
lance with the naked eye. Divide this by
600 the power Of the biggest telescope
and YOU have $3.50, the size Of the smallest
object plainly discernible at such a dis
lance with the telescope. This is equal u
about five miles.
"An object in the planet Mars could b.
perceived as little t.. ger than a dot viii
the aid Of the largest refraetor and undel
the most favorable, in fact absolutely per
feet, atmospheric and other conditions ]
it was five miles In diameter. This Is wnei
the planet Is nearest to us. On the Othe
hand. at that time nothing on the cary
could be discerned from Mars, because tn
earth would be in a straight line between
e and the sun and in the blaze Of the sun
light. An inhabitant Of that planet woul'
have to wait until the earth was in som
other part Of its orbit, andthe distance be
tween the earth and Mars would then b
, many times as great as in perihelion.
$50 It wOnld be necessary 70 construe
an object, to be discernible on the cart
from Mars, say, twenty miles In diameter
It might be circular in form. Other struC
, lures not inferior in size would have to b
, erected at distances Of not less than twent
, miles from each other. Then, after thes
had remained for time, their relative pc
3 gitions might be changed. These bodies
, moreover, to be clearly distinguished froI
3 the surface of Mars must BE- intensely u
I miuous. A solid ball Of electric hg1
twenty miles in diameter would suffice.
, considering the size Of the structure
8 required, their distance from each othe
t and the necessity of changing their place
, to Indicate to man In Mars that these 1t
g minous structures were the result OF int
/ liRent action and not natural phenomena
g the sum bequeathed by the French nu
{ may be seen TO be greatly inadequate. IN
Academy OF Sciences at Paris may for tn
e reason refuse to accept the bequest. II Il
T sum were offered for prize essay on SON
g plan for accomplishing communicate
: with sister sphere it would be more re-
sOnable.
d ''In all the above computations It mu
e not be forgotten that all the condition
must be favorable, the atmosphere as we
Q as the relative positions Of the earth an
d Mars. Such conditions happen only on
e in a great while. ~ Chicago Tribune