Stevens County tribune. (Morris, Minn.) 1877-1880, 1879-06-05
New Planets Near the Sun.

Perhaps no scientific achievement dur
ing the present century has been deemed
more marvellous than the discovery of the
outermost member $50 far as is knOwnl
of the suns family of planets. In many
respects, apart from the great difficulty
of the mathematical problem involved,
the discovery appealed strongly to the
imagination. A planet seventeen hun
dred millions of miles from the sun had
been discovered in March, 1871, by a
mere accident, though the accident was
not one likely to occur to any one but an
astronomer constantly studying the star
depths. Engaged in such observation,
but with no idea of charging the known
domain of the sun, Sir W. Herschel per-
ceived the distant planet Uranus. His
experienced eye at once recognized the
fact that the stranger was not a fixed
star. He judged it to be comet. TWAS
not until several weeks had elapsed that
the newly discovered body was proved to
be a planet, travelling nearly twice as far
away from the sun as Saturn, the remot-
est planet before known. A century on
ly had elapsed since the theory of gravi-
tation had been established. Yet it was
once perceived how greatly this theory
had increased the power of the astrono-
mer to deal with planatory motions
Before a year had passed more was
known about the motions of Uranus than
had been learned about the motion of any
of the cd planets during 1900 years pre-
ceding the time of Copernicus. 1t was
possible to calculate in advance the
position of the newly discovered planet, to
calculate retrogressively the path along
which it had been travelling, unseen and
unsupported, during the century preced-
ing its discovery. And now observations
which many might have judged to be of
| little value came in most usefully. AS
tromers since the discovery of the teles-
cope had formed catalogues of the places
of many hundreds of stars invisible to
the naked eye. Search among the obscr-
vations by which such catalogues had
been formed revealed the fact that Uran-
us had been seen and catalogued as a fix
ed star 81 several times! Flamsteed had
seen it five times, each time recording it
as star of the sixth magnitude, so that
five of Flamsteed's stars had to be can
celed from his lists, Lemonnier had act
| ud1Ay SccA CIduuS - IIulcS, anu only eS-
capped the honor of discovering the planet
Gas such) through the most marvellous
carelessness, his astronomical papers be-
ing, as Arago said, "a very picture of
chaos" Bradley saw Uranus three times.
Mayer saw the planet once only. 1t was
from the study of the movement of Uran-
us as thus seen, combined with the plan
cts progress after its discovery, that
mathematicians first began to supect the
existence of some unknown disturbing
body. The observations preceding the
discovery of the planet range over an in.
terval of 90 years and a few months, the
earliest observation used being one
made by Flamsteed Dec. 90, 1890. There
is something very strange in the thought
that science was able thus to deal with
the motions of a planet for nearly cen
fury before the planet was known. AS
tronomy calulated in the first place where
the planet had been during that time
and then, from records made by departed
observers, who had no suspicion of thu
real nature Of the body they were observ
ing, astronomy corrected her calculation
and deduced more vigorously the tru,
nature of the new planets motions.