Evening star. [volume] (Washington, D.C.) 1854-1972, 1900-10-20
SOLVING A PROBLEM
To Determine the Earth's Distance
From the Sun
BY MEANS OF THE PLANET EROS
Astronomers All Over the World
Are Interested.
HOW 1T WILL BE DON

Written for The Evening Star.
At the naval observatory in this city
work was this week commenced upon the
most important aStronomic problem which
today remains unsolved. Night and morn
ing, from now until the Sth of next Febru-
airy, will be made observations from which
will soon be deduced, much more accurately
than ever before, the earth's distance f.. n
the sun and the distance between all the
planets Of the universe
That science has not yet satisfied itself as
to how far Old Sol really is will surprise
the popular mind. We were taught at
school that daylight travels an average
distance Of 100000 miles from its source.
That is but very rough estimate. The exact
figures are greater. Nature has suddenly
supplied astronomers with an unantc. pa ted
means of revising the most scrupulous cal
culation yet made and making it as truly
correct as, in all probability, will ever be
possible.
New World Discovered.
| This means Is the new planet Eros"
lately discovered by Herr G. Witt of the
Uranla observatory, Berlin. Recent OBJ
| servations prove beyond a doubt that
Eros" ventures nearer to Mother Earth
| than any world having an independent
| orbit about the sun. Before the discovery
of this new world astronomers had figured
! out an ingenious method of determining
| the suns distance. But the success of
| this method long awaited the exact meas
urement of our distance from any other of
| our sister worlds. Eros, coming nearest
| of all, will give the most accurate distance
! ever calculated between sphere and
another. Having discovered how far Eros
| is from us the computation of how far we
are from the sun will then be matter of
| SlmD,e mathematics Astronomers desire
| the suns accurate distance from the earth
because they will use it their foot-rule,
so to speak, for measuring all heavenly
| space. That vast gulf is now measured in
| fractions Of imaginary rod extending
from our world to the central orb of day.
| Astronomers have plotted the heavens,
| far and wide, high and deep, into huge
map showing all worlds and their paths in
| proper proportions. Give a single distance
on this map and given it accurately they
can estimated the long wanted scale of the
| map. Thus the accurate estimate of how
far Eros is from will enable science to
correct Its doubtful computations of the
| great scale upon which the whole universe
around US is constructed. Tables of dis
| tances in all ASTRONOMERS used by schools
| or observatories will have to be altered
after the new figures have been worked out.
Could BE Circumnavigated in an Hour
Eros is a tiny world, less than twenty
miles In diameter. Were 1t to fall upon the
broad breast Of America and attach itself
thereto 1t would form lump but little
more than twice as high as the loftiest
peak of the Himalayas. Standing alongside
the moon In space it's face would measure
only one-hundredth the breadth Of the lat
| ter. A man might walk from it's north to
| its south pole in a day, while an express
train might circumnavigate its equator and
return to its starting point in an hour.
Yet this insignificant planet is given a year
one and three-fourths the length of ours.
To- al f1,.,v,
of the earth. The sun, rather than occupy
ing the center Of this oval, stands much
| nearer to one of it's ends than to the oIher.
At one season Of its long year Eros strays
165, 100000 miles from the sun. Then 1t
turns the far end Of its great oval race
track and returns to an opposite point
1O5, 900, 900 miles from the sun. At the same
time our planet hurrieS about the same sun
on more circular race track. inside that
of Eros and in the sunny half of it. Our
path keeps us at an average distance OF
about 93OOO,00O miles from the sun. (All
Of these round figures, of course, depend
upon the old scale shortly to be revised.
1t is while Eros is making its course around
the sunny end Of its oval that the little
world comes closer to ours than any other
planet. The earth is then sometimes be-
tween the sun and Eros. the latter being
almost in the plane of our orbit The near
est of such approaches on the part of Eros
occurs just once in thirty years Then 1t is
only 4,000, 600 miles distant from us.
Eros next nearest approach will be In
1924. Yet it will be nearer the earth than
it has ever been seen before on Februar y
next. During the darkened hours of thai
day it will appear in the Milky Way From
now until then it will continue to approach
US. During all this time astronomers
throughout the world will closely watch
and measure 1t. The nearer the little
world ventures the more accurate viii
these measurements become. The figures
having all been carefully checked up ant
compared, the distance of Eros will be an
nounced and accepted by astronomers
everywhere as the most accurate measure
ment ever made through interpanetary
space.
Is Invisible to the Naked Eye.
Eros Is now invisible to the naked eye
and will be so even on February s. 1t will
remain invisible. except through the tele
/ scope, until its next nearest approach Their
it will be barely seen in the heavens with
t OUT the aid of that instrument Through
!, the greatest telescopes 1t appears a.
; the merest pin-point of light. 1t will neve
exhibit round disk of measurable breadth
no matter how highly magniied
Telescope measuring instruments can b.
aimed more accurately upon a mere poin
/. than upon a broad disk, like that of TIL
, moon. Thus in Eros are combined. bette
! than elsewhere, the two prime virtue
+ which planets could offer the careful meas
a urer of vast distances. These virtues ar
| rearneSS and SmallneSS.
Above we have said that Eros come
| nearer to the earth than any planet havin!
q an Independent orbit about the sun. Blu
: | we should not forget that the moon, onl,
23s 600 miles away, is our nearest celestia
: neie hbor; yet the moon is only a secondar
e planet-a small satellite of the earth-whic
o | has no Independent orbit about the sur
h She could not be utilized In careful meas
+ uIement of the suns distance.
o The MOdus Operandi.
If two men a hundred feet apart air
their rifles at the same target an
simultaneously hit 1t, the sharpness of tn
angle made by the paths of their bul
lets in coming together will depend upo
HOW THE FLY SPOIL