South Bend news-times. (South Bend, Ind.) 1913-1938, 1918-04-22
Wonders fStarhght
BY GARRETT p. sERvIss.

There are about 225,OOO,00O stars
within reach of the largest tele-
scopes now in existence. Judging
from the decreasing rate at which
the numbers increase with increase
Of distance, it is estimated that
there exist not much more thar a
thousand million stars which can
not at present be seen with our in
struments. although their contribu-
ton 10 the total amount OF starlight
may be measurable quantity. In
divijually they are imperceptible,
but the sum of their rays, coming
from all quarters of the sky, is not
only about one-quarter as much
light as the single star Sirius.
The total amount of starlight fall
ing upon the earth is probably
equivalent to about one-hundredth
of the light of the full moon, and
nearly three-quarters of it is con-
tributed by stars, all of which are
too faint TO be individually visible
TO the naked eye. and the vast ma
jority of which can only be seen
with the most powerful telescopes.
II you are driving along a cOun-
try road, on a moonless and cloud
less night, with tall trees shutting
i'm the roadway on both sides, you
see overhead a faint streak Of sky,
with a few bright stars, like cleo
trio points, and you may think that
the dim, barely perceptible illu-
mination that falls between the
shadowy banks made by the trees
is due TO those visible stars
For a fact, however, it is prin-
cipaly due to multitudes of invisible
stars buried deep in the fathomless
background of space, and about one
quarter Of one per cent of Il has
come from the distant realm of that
thousand million stars which no
telescope can reach, and whose light
waves have been, on the average, at
least 10000 or 10000 years on their
way before reaching the earth. Yet.
if we could go out among those stars
we should probably find that, like
the nearer ones. they equal our sun
in average luminosity.
1t is distance, not smallness, that
makes them separately invisible.
Thirty thousand light-years Ga
liCht-year is the distance light trav-
els in a year,, are about 175, 900
600 600. 900. 900 G75 quadrillion)
miles. which is not much less than
two thousand million times the dis
lance of the sun from the earth!
Now. to see what effects relative
nearness com bined with size pro-
duces, take the brilliant star Sirius.
which is about fifty trllions of miles
distant and between so and 40
times brighter than the sun would
be at the same distance. About
one-thirteenth OF all the light sent
10 us from the stars clearly visible
TO the naked eve comes from Sirius
alone, although the others number
several thousands. Sirius contributes
about one sixty-third part of the en-
tire starlight furnished to our night
sky by the whole known universe,
with its twelve or fifteen hundred.
or possible two thousand million
stars.
Now. if the star Campus. which,
as We see il in the sky. is. owing TO
its vast distance. only about half
as bright as Sirius, were put in the
place of Sirius it would give us at
least two hundred and fifty times
as much light as Sirius does. and
more than one-third OF the entire
starlight falling on the earth would
come solely from that tremendous
star. Moreover. il would give near
IL 20 times as much light as all the
naked.eye stars down 10 the sixth
magnitude combined.
II NAV be that in that part OF
the universe where Campus shines
supreme all things are made on a
vaster scale than that which rules
in our dim quarter. And 1 have
been. perhaps. belittling Campus.
for 1 have taken the moderate es-
innate that his luminosity exceeds
the suns 10000 times. whereas some
astronomers reckon his superiority
over the sun at $4,000 times.
At least two other giant stars be-
sides Campus have been detected
Climmering across space like
mighty CONGREGATIONS minimized by
distance 10 specks Of light. one OF
them is the beautiful star Rigel. in
the foot OF the constellation Orion.
star that carries an exquisite blue
companion almost hidden in its
diamondShright rays and the other
is the star Deneb. az the head Of