Public ledger. [volume] (Memphis, Tenn.) 1865-1893, 1876-10-03
AN ASTRONOMICAL EYENT.
Saturn with n EsiEhbOriy Turn Rum
Mug uOWn Toward Oar Planet.

Saturn with n EeighbOrly Turn Rum |
Mug DOwn Toward Oar Planet.
On the 9th of August there was
an occultation of the planet Saturn
by the moon, and unusual interest
was excited among astronomers by
reason of the beautiful scene which |
the telescope revealed on that occa-
sion. On the Sd of September there
was another occultation by the
moon in the morning. On the
27th of August Saturn was in OPP
position to the sun; that is, the
sun, the earth and the planet were
in the same line, the earth occupy
ing the middle place. 1t is some
what remarkable that all the occul-
tations occurred on Sunday.
The use which the opposition
of the 9th will be made to serve
is to test certain conclusions de-
Quoted by the French astronomer
Trouyelot in memoir on the
physical aspects of the planet
Saturn. This memoir was pub
lished, with illustrations, in Sill
mans Journal. One of these con
clusions was that the inner margin
of Saturn's outer ring has Tor
several years shown Jagged forms
near the handles, which would in
dictate irregularity Of structure;
another is that the thickness Of the
whole ring system Is increasing,
and that the inner ring is not en-
tirely transparent, although more
nearly so than the planet. This
system of rings renders Saturn q
unique member of the planetary
family; and as modern investiga-
tions tend somewhat to show that
we have in it an evidence of the
truth of Leplace's hypothesis of the
original formation Of our system,
the importance attached to a care
full observation of the latest oppo-
sition by astronomers may be
readily appreciated.
Saturn is now only about 1872
100000 miles from this earth, in
stead of $40, 10000 miles, its great
est distance. 1t is this difference of
1873, 100000 miles which makes the
period of an opposition SO impor-
tant to the star-gazers.
Saturn is the oldest of the
worlds that compose the known
system of the universe. He is
qixth in the order of distance from
the sun. When viewed through a
strong telescope his disc appears
striped with dark belts, which,
from their parallelism to the equa-
tor of the planet, arc believed by
some scientists to have been deter
mined by currents similar to our
trade winds. He is attended by
eight satellites, who have been
since the beginning OF time pune
tual and regular in their attend
ance. lie is changeable in charac-
ter and never presents Tie same APP
pearQnce twice in succession. For
this apparent eceentrieity the as-
tronomers give the reason that SINCE
the eayth's mean distance from the
sun is 9l,0O0,00Q miles, Saturn
when in opposition to 1t is distant
| 732,000,000 miles when nearest tho
sun, and 3S0,000,000 miles when
furthest from it. AS the plane of
Ais rings is inclined te the ecliptic
aud maintaips its paIAlelisms dur
| ing the revolution Of tie planet,
the angle under which it is pre-
sented to the sun Is continually
changing; the appearances which
| it presents to the earth are, there
fore, also continually changing.
The ripgis visible only when The
sun and tie earth arg ep thp same
side of it, but it becomes Invisible
when its planet passes through Che
center Of the earth, as we'll as when
it passes through the center Of the
sun. On this account, says Sir
John Herschel, two or three disap-
pearaaaes Of the ring may happen
in a very short space Of timG, The
disappearances take place about
every fifteen years, or half the time
of Satun'S revolution in his orbit,
and the two sides Of the ring have
alternately fifteen Years of sunshine
and fifteen years OF darkHess,
Saturn rises in opposition when
the sun sets, and may be readily
found early in the evening coming
Iup in the southeast. 1t will be the
prominent evening star for some
time to come, and after ten o'clock,
when Jupiter sets, the only visible
planet during the night. The star
gazer cannot mistake Saturn. He
has no bright neighbors, and il he
had, tho lurid, dirty yellow light
that he sheds would alone be spfii,
cient to mark him.