Iowa voter. [volume] (Knoxville, Iowa) 1867-1874, 1873-12-18
A Look at The Sun.

From Report Of q Lecture by Professor Proctor.
ATTENTION was then directed to the
sun. Many well-informed persons look
st him, and forget what he really is.
They recognize him as the ruler of the
day and of the seasons, but forget the
tremendous operations which are going
on In this wonderful orb. First, as to his
SAGE, compared with which that of the
earth sinks to insignificance. In coming
to this country he had, during the thir-
teen days journeying across the ocean,
obtained some idea of the magnitude of
the small arc of he earth over which he
passed, and so of the whole earth. From
this an improved idea of the suns magni-
tude could be gained Drawing two
short lines, about nine feet apart, on the
blackboard to represent the SUMS diam
eter, circular dot of an inch in diane
ter showed the comparative size of the
earth. In figures the
Suns diameter is 10S times the earth
" area is $1,000 +"
:. volume is 1,250,OOO {"
But 1t is important that we should con-
slider not only the size, but the mass of
the sun-that is, the quantity of matter it
contains, for this is the real measure of
its power as controlling body. Some
comets tails are estimated to have a vol
umc which would fill sphere of the size
OF the earth's orbit, but their mass is ut
terly insignificant. The mass of the sun
is $4,000 times that Of the earth. Sup
posing the earth to contain the same
quantity of matter as the sun and to re-
main the same in size as at present, a
body lifted a single inch would fall with
the velocity of an express train. Every
thing on the surface of the earth would
be Bis, 900 times heavier than at present
But the sun is 10S times larger in diane
ter than the earth. Square this number
and we have the ratio of diminution of
attraction at the surface, due to increased
size, viz, 10000, and dividing $4,000 by
this we find the actual ratio of increased
attraction about twenty-seven This
should be borne in mind, that at the sur
face OF the sun gravity acts twenty-seven
times more powerfully than at the sur
face of the earth. The mass of the sun
far exceeds that of all the planets COM
bined.
Next consider the light of the sun and
its extreme brilliancy. BY the oxyhy-
drogen light we can get an intensity of
one 146th part, and by the most powerful
light one-third part that Of the sun. The
power Of his chemical action we are unable
to gauge. We have better means of
measuring his heat though strangely
wide variations still exists in his esti-
mates of his temperature. The quantity
emitted is well acertained. Herschel and
Pouillet calculated that the power of the
suns heat, if poured vertically upon a
circular area of the same diameter as the
EARTH was sufficient to melt 26, 900 tons
OF ice over every square mile per hour,
or to raise the temperature of an
ocean of the same size GO feet in depth,
from the freezing to the boiling point.
But these enormous quantities of heat
are entirely insignificant when compared
with the whole quantity emitted by the
sun. The earth seen at the sun
would be mere telescope point
1t would take $4,000 Of them TO reach
entirely around him in one line; then
consider that the whole celestial sphere
receives the suns heat. All the planets
together only get one 227 millionth part
of the entire heat Of the sun. This is one
of the most perpiexing facts of science,
the apparent waste Of all this enormous
heat. Not only the sun but the stars are
thus throwing out to waste this tremend-
Gus energy.
A convenient mode Of remembering the
distance to the sun is found in the aproxi-
mate equality of the ratio between the
diameter of the earth to that Of the sun,
and between the suns diameter and his
distance from the earth. Light, heat and
magnetic influence travel from the earth
to the sun in about the same time, some
eight minutes. If sounds could be heard
from the sun, and doubtless most terrific
sounds are produced there in those ire
mendous eruptions and cyclones, which
we shall hereafter consider, the time re-
quired to reach the earth through an
atmosphere like ours would be thirteen
and half years. If those sun-worship-
ers who formerly prayed with loud voices
to the sun had realized the length of time
thus required TO obtain hearing, doubt
less their worship would have been
abandoned. Laughter. But consider
an actual contact Of steel rod which
might be supposed to connect the sun
and earth, a pull or push at one end
would not produce its effect at the other
in less than 300 days. The rates ofpropa-
cation Of sensation have been measured.
III baby were born with an arm long
enough to reach the sun he would live TO
old age and die before he would know
that his finger was burned there.
Laughter II the gravity Of the sun
required time for its transmission the
earth would be pulled forward in its orbit,
and the length of the year increased. AS
no such increase had taxed place gravity
acts instantaneously. This is most
surprising fact. Herschel proposed TO
account for ii on the idea that the ether
was actually solid and pulls were trans
mitted directly through its immoyable
substance
The sun spots were noticed as long ago
as 1910 and 1911, when Calico and others
observed them. Later, Wilson noticed
indications, as the spots approached the
suns edge, that they were caotties in the
sun. This is true Of most Of the spots,
and generally Of those having a rounded
form. The figures on the diagrams show
a white matter across the spots. This
was seen to fall behind the spots, the
reason being that it was matter thrown
up into higher region, where the veloc-
ity Of rotation would have TO be greater to
keep up in angular velocity.
Laws had been discovered regulating
the increase and diminution of the sizes
and number ofthe spots which occurred