Evening star. [volume] (Washington, D.C.) 1854-1972, 1890-03-15
FROM JUPITER TO NEPTUNE.
Prof. Searle Talks About Little Aste.
roids and Great Planets.

The subject Of Prof. George NJ Searle's lee
poon was ''The planets from Jupiter to Nep.
une." He began with::the statement Of the sup
posed law according to which the distance,
from the sun seem to be arranged. A break In
the series, according to this law, occurring be-
tween Mars and Jupiter gave rise to the sus-
picion of the existence of o planet TO fill the
gap. This suspicion was strengthened by
the discovery in 1871. of Uranus,
the distance of which beyond the
farthest known planet seemed to conform
to the law Of Bode. Organized search for the
planet between Mars and Jupiter was com.
menced by twenty-four astronomers, mainly
Germans, but, strange to say, the planet was moi
found by any Of these, but by Father Piazzi,
religious Of the3Theatine order, who was then
constructing his celebrated catalogue Of fixed
stars. The planet found by him on the LIST OF
He observed it for several weeks, until it was
lost in the rays Of the sun. The question was
now how to find it again. There had been plenty
of opportunity to observe Uranus, and to cal
culate Its orbit at leisure, but that Of this one
had to be determined from q few observations
covering only small period Of time. The
celebrated mathematician Gauss invented for
this occasion his method of computing
orbits, and furnished an orbit for
Ceres by which it was found on the 3lst
was shortly after followed BY the discovery Of
Pallas by DR.. Olbers that OF Juno by Hardy
and that of Vesta by Oilers again in 1907. Nc
more were found for q considerable length OF
time and those Of rs who are we'll advanced In
life remember, perhaps, being taught in text
books that there were four asteroids. The
reason why no more were found is probably
that the search was not made for small enough
stars.
In 1845 another asteroid was found BY the
amateur astronomer Hencke, after Is years OF
search. Since then they have been picked up
and eighty-eighth having been found on the
oath of last February. A slide was shown on
the screen copied from the journal announcing
the discovery of this planet.
The lecturer then passed on to the planet
Jupiter, giving the figures in regard to the
satellites. Various fine stereopticon view,
were given exhibiting the planet and III
satellites with the markings on It's surface, and
particularly the great red spot which has at
tracted so much attention in recent times
Account was also given Of the discovery Of the
velocity of light from the eclipses Of Jupiter
satellites The surface Of Jupiter was stated
to be probably covered with clouds, and il
perhaps in molten condition, as it seems to
be in more active state and to give more
light than would be due to that reflected from
the sun.
A number Of beautiful views Of Saturn and
its ring and satellites were also shown. The
structure Of the ring was stated to be probably
meteoric, that is to say that it IL composed OF
mass OF small independent bodies.
An account was given of the discovery of the
planets Uranus and Neptune, the latter Of
which has been justly considered ~ the creates,
triumph Of mathematical astronomy. Prof.
Searle closed with some interesting statements
in regard to the amount Of sunlight thai
reaches the planet Neptune. Although the
sun gives there only about one nine -hundredth
part of the amount of light which the earth re.
ceives from it. it is not 30 family visible as ID
commonly supposed, but, on the contrary, has
been shown to shine In Neptune with briliiancy
equal to that Of an electric arc lamp distant
only few feet-that is to say, about 100 timei
AZ brightly as the full moon.
The subject Of the next lecture, to be given
next Friday afternoon, will be Comets and
meteors."