Evening star., 1898-06-04

times referred TO as the "globular cluster"
1t is situated on the western side of the
trdpezfGn. a small telescope shows Ii
merely as a round nebulous spot; a large
instrument resolves it into several hundred
tiny stars-S23 is the number given by Prof
h g Pickering-arranged, apparently, in a
globIlar form
But more Interesting to US than this teIe-
scopic object is the fact that this constel-
lation contains, according to the observa-
uons OF Sir William Herschel, the point to-
ward which the sun and its family of plan
cts are travelling in space.
We were speaking last month of the
proper motion of the stars. 1t is prob
able that nCne Of the stars is really fixed"
but that all of them are travelling, with
greater or less rapidity, in various direc-
tiers, though SO distant from US are they
that centuries are required to effect any
changes of relative position perceptible to
the naked eye. Our sun Is only star
Hence Herschel conjecsured that H. Ike
its brethren, was in motion-Was travelling
mewhither. To detect such motion, if it
exists, is matter very simple in principle.
When We move in any dire surround
ing objects appear TO move in the contrary
direction. They seem to move from the
point toward which we are going toward
the point directly behind us. Were the sun
the only moving star in the universe
were al the other stars fixed like trees in
fCrest. and were our conveyance alone in
motion-there would be little difficulty in
determining the direction in which we were
moving. We should need merely to observe
atteGtTeiy the apparent movement of the
stars-its We might observe that of the
trees of a forest through which we were
Dassins-aHd, knowing the appearance to
be deceptive. we would judge of the direc-
ton OF our own movement accordingly.
A Complicated Problem.
But since the stars are themselves tray
cling in all directions. the actual problem
is a complicated one. 1t is oaly after max
ing sort of general average of the direc-
uons and the amounts of stellar proper
motions that we can reach some conclusion
as to the direction in which we ourselves
are going. Herschel found hat on The
whole the movement of the star3--the ex-
cess of their proper motions-was toward
a point ABOUT twenty degrees southwest of
the star Sirius, and from a point in the
opposite part Of the heavens, nea.' The star
Lambda HercIlis, and accordingly ne fixed
upon this point as that toward which The
sun mcves-the apex of the suns way"
as this point is now called by astrono.n ars
The point fixed upon by Herschel is
marked on our planisphere by dotted cir
have confirmed HerscheTs conclusion in
the main All who have nade the matter
a subject OF investigation agree that the
sun Is moving toward this part of the
ftdFens, though no two astronomers have
placed the apex of the movement in pre-
cisely the same spot. The point fixed upon
by the elder Strive Is marked on our chart
with Il letter S One of the latest to at
tempt solution OF this problem Herr
Stumpe. after an exhaustive discussion of
four different sets of stars, came to the
conclusion that the point in question is in
the constellation of the Lyre, very nearly
at its center. The rate of the movement
according TO this astronomer. is eie mt miles
a second, or about 100 900 miles a year
Hypothetical Central sun.
1t was once held to be probable that the
stars were arranged on the same general
plan as the bodies of the solar system. ana
that they were all moving around a central
sun or, perhaps, around dark, invisible
body. The only astronomer of the present
century, however, to hold this view was
Maedler, who Went so far as to fix upon
the star Alcyone, in the Plciades, as
probably the great central body about
which reviewed all the other stars, the sun
included. Maedler's view has been widely
published in popular works on astronomy:
but no other astronomer has regarded it
with favor. The proper motions of the
stars have been observed for too short a
time to enable astronomers to say whether.
there is any center Of the movement much
less to fix upon its locality.
The Planets.
Mercury will be visible in the east, a
morning star, until after the middle of the
month. 1t will be in conjunction with the
Sun-behind the sun-on the 30th.
about two hours later than the sun.
Mars is morning star in the corstella-
tion Aries. rising at about am, little
north of east.
Jupiter is still a magnificent evening star.
in virgo. remaining above the horizon until
after midnight.
Saturn. in the Scorpion, six or seven de-
Stees northward of Antares is above the
hCrizon all night. This planet was in oppo-
sition To the sun May 30. 1t now shines
with its greatest brlliancy, closely re-
sembling Arcturus, both in brightness and
cOlor-orange-yellow. The rings are now
open nearly TO their widest, that the
planet is now at its best telescope
OF ijcct. Unfortunately, however it runs
low" being now near the point in the
heavens where the sun is al Christmas
Uranus also is in the Scorpion, a trife
more than one degree below the star Beta
Scorpii-as shown on the planisphere-and
therefore easy to find. 1t shines as a star
of the sixth magnitude, just within reach
of the naked eye. 1t can be seen easily
with an opera glass.
Neptune Is morning star in Taurus.
The sun enters Cancer on the 21st of the
month, at am, Washington time.