The evening times., 1900-09-29

second hontH ok
of Astronomy Due to 0bserya-
tion and MathematiSuI Analysis.
During the month OF October the moons
phases will be as follows: First quarter
on the 1st and last, full on the Sth. last
quarter on the 18th and new on the 23i-
She viii be in perigee on the Sth and n
| apogee on the 21st. The sun will be lit
tie ever degrees south OF the equator on
the 1st and in the course of the month
traverse an arc of over IL degrees Oh
south decIination, so that at the eonclu-
sion of the month it will be nearly IA de-
| grees % seconds south of equator and
| about degrees from its southern limit.
| the winter solstice.
The planet Mercury will be suecessively
in Virgo, Libra, and Scorpio, while Venus
will be in Cancer the greater part of the
month, but enter Leo toward its term1na-
tion. She will rise soon after o'clock in
the morning during the earlier portion oi
the month, bat near o'clock during the
later. Venus is still very brilliant ard
certainly the finest object in the morning
skies. Up to the time of the famous Gal
leo, in the first portion of the seventeenth
century, it had been believed that Venus
could not show US more than half her IL
| Illuminated surface, since according to the
Ptolemaic hypothesis she was always be-
tween US and the supposed orbit OF the
sun. When, therefore, in the year 1910
Calico. by means of the telescope discov-
cred by him, proved that Venus showed
the gibbous phase as we'll as the cres-
cent, the Copernican theory of the solar
system received a very powerful argument
in its favor, since this fact certainly dis
proved the general truth of the ancient
system.
The planet Mars is in Cancer and rises
soon after midnight, also forming a bril-
/ liant object in the morning skies, since IN
| brightness it exceeds all fixed stars except
Sirius. Jupiter is in Seorpio. This beau
! tifuI planet forms with Antares the bright
! est star in that cons tellation, and at pres
! ent at a short distance from the kingly
planet very fine stellar picture and can
not fail to engage the Observers attention
until about 80, when it Will vanish from
our view. About Is degrees above Jupiter
| the planet Saturn, too. will shine IS an
| evening star in the constellation Sagitta-
! rius almost on the confines of that con-
stellation and Ophiuehus. Saturn will set
about an hour later than its brother plan
! ct Jupiter.
The great results which the science OF
| astronomy so pre-eminently has achiev
| ed are due first TO patient observation,
| and second TO The application Of nathe-
| matical analysis. The splendid develop
| ment of physics and chemistry too, nave
| contributed in a vast degree to some Of
| the most important astronomical disCoy-
! cries, especially as to the physical na-
| ture OF the heavenly bodies. II is a cri-
terion of the power and greatness Of
| science. if it can make other sciences
! tributary to itself. just as the magnitude
! of a river is commensurate with The
| number of its tributaries. We are apt
| to smile with contempt at the numerous
! and rigorous efforts of former ages to aC-
/ complish the exact Guadrature of the
| circle the trans mutation of metals. the
| perpetua motion, all of which have now
become a venerable paradox. but we un-
| fortuna tely become oblivious of the fact
| that some of the most interesting and
| important branches of modern pure
| mathcmat.' sprung from the problem of
squaring q circle; we forget that the
| researches of the alchemist develC ped
| into the science OF modern chemistry and
| that the vain efforts of the GstroIOger at
| prognosticating the future events of a
| human / .e by the conjunction of plan
| cts gave rise to a profounder study Of
! the stars, and the result Of the vain re
| search after perpetual motion termi
| mated in the greatest of all the general
| iZations of physical science-the princi-
/ pie of the conservation of energy. Be
fore the Invention of telescopes the OBJ
| seTvation of the planets and stars could
| not give US much valuable information
as to their sizes and distances. but with
| our present wonderfully improved in
/ stFuments and with the aid of the high
ly developed sciences of physics and
! chemistry we have gained an incom-
N oh fads
| it was possible formerly, not aIcne Of
| the comparatively near planets but also
| of the enormously distant fixed stars
| themselves.
Copernieus, the founder of the present
! solar system; Kepler, who subjected 1t TO
| fixed laws, and even Newton, who placed
| II upon mathematical and solid basis and
| thereby established its truth beyond the
shadow of a doubt, would perhaps have
! smiled at the idea of a proper motion Of
the sun and the fixed stars, as at those
| times the means were lacking of O. iecting
| an almost infinite displacement OF stars in
their relative position, while now these
| motions are no longer matter of DOUBT
| among intelligent people. If Newton :
| great law of gravitation is true-and might
| We not just well doubt the universality
| of that law as that of the multiplication
| table wherever reasoning beings deal with
| numbers the proper motion of all the
!
| sity and We are irresistibly forced to ad-
nit that in the whole universe there is
! not point in a state of absolute rest ex>
! cept the centre Of gravity of the whole
| wherever that may be. This is an ire
sistible syllogism, the truth of which no
! skepticism can invaiidate- 1t is strength
| ened by the fact that quite a large num-
| Der Ct stars have been actually seen to be
| In motion. It is true that in the majority
| Of cases the change of position of stars by
virtue of this proper motion amounts to a
/ few seconds of are in a century, buE the
power of our present telescope is such that
| the motion can be detected in the course
| Of 4 few years. The brilliant star Arc
| turus which for some time may still be
seen in the western portion of the skies.
| is one whose proper motion is exceptional
" great, being between 200 and geo miles
| per second. The discovery OF the star Of
| the greatest known proper o-ion was
made in 1897 by means of photography at
/ the Cape Observatory Still rapid as its
motion is. it would require nearly 150, 600
! years for that star to make a complete cir
| cult of the heaven were it to move round
| the sun uniformly at its present rate
! The proper motion of the sun IS, OF
| course of special interest for us dwe1Iers
of planet on which every manifestation