Iowa voter. [volume] (Knoxville, Iowa) 1867-1874, 1874-02-26
The Wonders OF Astronomy as Illus.
trated in the Star Depths.

AhV WVuuCAS VI iAStAOuOMy ~ Illus
trated in the Star Depths.
PROF. r. A. PRocToR has been delivering
series of six lectures in New York city,
on astronomy, which have been published
in the New York papers. The fifth lee
ture of the series was on "The Wonders
of the Star Depths" which is said to be
superior in scientific interest and enter
| tainment to any of the others. We are
| indebted TO the Herald for the following
| interesting analysis of this lecture:
| The lecturer first considered the ques-
| tion of the seeming calm of the star
depths compared with the real vastness of
the movements taking place in them. He
opened by recalling to the minds of the
audience the gradual change of the
earth's rotation due to the influence of the
tidal wave: but SO slight is the effect of
this disturbing cause that 1000 years
must elapse before loss equal to three
minutes of terrestrial time will re-
suit. Millions of years must, there
fore, elapse before any perceptible
| change takes place from this
cause. The stellar sphere is carried
through space from east to west. Other
motions are perceptible, but they are only
apparent They are due to the earth's gy-
rating like a gigantic top, which causes
an apparent motion in the heavens. The
quietude of the stars is only apparent; for
though they are relatively fixed, they rush
in tn multi through space, and though
the heavens seem at rest they are
the scene of most stupendous activity
Among the multitude of stars visible, the
distance of some nine or ten only is APP
proximately known, ana indeed the dis
tance of one only can be said to be salts
factorily determined, although the prob
lem is of the deepest interest. The change
OF one star in the Centaur has been no
.iced, and in order to show the delicacy
of the observation and its difficulty the
lecturer remarked that this star was re-
moved from our earth 10000 times fur
ther than the SUM- In order to indicate
the change of position, il would be neces-
sary TO imagine the minute hand OF a
watch marking the two-hundredth part of
a second, and the deviation of the line
drawn to the star to mark It's change OF
position would be less. Nor is there any
way Of measuring the discs of the stars,
as the best telescopes fail to show them
except as points of light in space. Their
distance is measured by light The star
in the Centaur is go, 900 times further of
than the sun it shines three times as
brightly, and is five times the suns vol
ume. But there is another star in the
space known as the king of stars. 1t is
four times as bright as the star in Cen
taur and five times as far away,
These facts would seem to point 10 the
existence Of higher order of stars than
our planets. 1t was cOnjectured that
these bodies might have size and light,
but not mass, and were therefore unable
| TO exercise control in the systems or in
| fuence other bodies But spectroscopic
| analyses allow us to ascertain in most
precise manner that the stars are, like our
| sun, glowing masses of matter shining
through surrounding envelopes of vapors.
| The value Of the spectroscopic analysis
| is due 10 its extreme delicacy, and the
strictly scientific and unvarying results
which ii gives in recording the presence
of certain elements in the planets. In
order to make this clear TO the audience
spectrums OF the sun and OF the variable
stars, and the sun spots on the stars were
exhibited, so as to make clear the mode
! in which the presence of certain matters
was made evident on the different heaven
| " bodies. There were the lines on the
spectrum indicating the presence OF
metals common to the earth. These ex.
periments were as certain as II the Oh
server carried into his laboratory piece
of the star and subjected 1t to chemical
| examination. The spotted stars were
variable and resembled our sun. The
specroscope proved the existence in them
of metals and other matter in certain
form. The question whether color is in.
herent in colored stars or due TO the cut
| ting off of some color by the action OF
an atmosphere or envelope is full OF IN
terest Great difference is shown In the
spectrums OF these stars-blue prevailing
in some, orange, red and yellow in others.
1t is now generally accepted that color Is
not inherent in these bodies, but is due to
the action of their envelopes on the light
| passing through.
A beautiful diagram of stellar group,
supposed to be cluster ofsuns, was exhib'
| tied by Mr.. Proctor, presenting TO the minds
eye the vision of world without night,
where noontide splendor would exist un'
ceasingly, and the skies know no night.
Ifthese worlds were inhabited the dwell
ers would be shut off from all knowledge
of the existence of other worlds. They
would never behold the splendor or the
bLafry heavens WHICH buiiOuuu lISih va
every side, and would have no idea OF
space. Passing on to the consideration
Of the nebule, the lecturer produced
very fine diagram of the nebula In Orion,
which showed clear evidence OF the
dynamical process. The mass Of nebula
| floating with clearly marked spiral
motion showed that il was not matter
travelling in space, but nebule passing
| through matter less dense In order 10
demonstrate the enormous extent OF the
nebuln the lecturer reminded the audience
of the immense diameter of even single
star OF the thousands enveloped by the
cloudlike nebul@ which spread over
space. Reviewing rapidly the theories
about the milky way and the efforts Of
men like Herschel to lay bare the arcbi
lecture of the heavens, and illustrating by
diagrams the curious theories built up by
astronomers, the lecturer proceeded II
show In what these theories were defect
i've and opposed 10 the discoveries made
| In late years. The attraction OF the stars
toward some unknown point in space was
| explained and illustrated By diagram
showing the motion and direction OF
group OF stars and marking the progress
they would make In $4,000 years TO the
point TO which they are tending.