The times. [volume] (Washington [D.C.]) 1897-1901, 1900-11-04
WATCHING A Tiny STAR
Astronomers Pointing Telescopes
at the New Planet Eros.
One of the Unknown Worlds That
Approaches the Earth Only About
Three Times in the Course of
Ccntury-NOw Only About Thirty
Millions of Miles Distant.

The astronomer at the Naval Observa-
tory. as at almost every similar institu-
ton throughout the world. are at the pres
ent time nightly watching little star, SO
small that it can only be seen with five
inch telescope, and not perfectly visible
except with an instrument twice as large,
but dignifed by being classed with the
planets, and having a name, which is Eros.
Although it is so very small. its impor-
lance is extremely great, greater. in fact,
than any object that has engaged the at
tention of astronomers for some time, for
by means OF it the scientists hope to be
able to fix the distance of the sarth from
the sun much more accurately than here
tofore. Since man began to observe the
heavens the distance of the earth from the
sun has been a subject of speculation and
investigation. At present it is known to
be between ninety and one hundred mil
lions Of miles, and it is expected that after
all the observations of Eros have been
made and the results figured out the ex-
tent of space separating one planet from
the great source of light will be much
more closely determined The reason why
Eros is OF Importance in determining this
distance is because 1t is at present much
nearer the earth than any other heavenly
body ever comes, with the exception Of the
moon and occasional planets. Being now
about thirty millions OF miles from the
earth. Eros will continue to approach until
the last OF December, when it will be only
half that distance away. This is a great
many millions of miles nearer than Mars
ever comes Being thus comparatively
near neighbor of ours. the distance of Eros
from the earth may be very accurately de-
terminel
When this distance is learned by means
of geometric computations from the re-
suits of observations made in different OBJ
then with formulas and rules
which have been proved AMI through a
known ratio of distance to time o. circlinS
the sun the distance of the earth from the
sun can be very accurately determined.
At the Harvard Observatory in Cambridge
nearly the whole force is now 'ngaged in
watching oil phOtographing the little plan
ct and in maxi Z computations from the
results of their vigils Prof. Pickering is
almost nightly observing Eros with a
large telescope. Two Draper tnlescopes-a
eleven and an eight-inch-are used for
making photographs OF Eros, From the
photographic plates the exact position OF
the planet with relation to the neighboring
known stars is learned and also its iuaS-
nitude With the eleven-inch instrument
the plates are exposed from one to five
minutes but with the cmaller telescope
an exposure of from ten minutes TO two
hours is given. Numerous plates are made.
and the same stars are photographed sev-
eral times upon :hs same plite. the plate
being moved to keep mp with the move
ment of the stars. II is now thought that
the little planet is about the tenth mag
nitude and some thirty million miles away.
It is moving nOrthward and is in the con-
stelation of Perseus. On November IL 1t
will have reached its maximum northern