The Richmond palladium and sun-telegram. [volume] (Richmond, Ind.) 1907-1939, 1910-03-19
COLOSSAL ARCTURUS.
The Fourth Brightest Star In al
the Heavens.
IN REALITY A MONSTER SUN.

u 10 Thought 70 Be At Least . Hun.
drsd Times Larger Than Our Sun In
Diameter and 10 About Nine Hun
drsd and Fifty Million Miles Distant.
Most Of us are prone to think OF our
sun as being the largest body In the
heavens, the grand high lord Of all the
little planets and the twinkling stars.
Such is very far from being the case.
Practically all Of the fixed and twin
king stars are Al large as, aud some
even larger than. our own sun. They
appear small only because Of their great
distance, for they are just as truly
suns with families Of planets flying
around them as is our central orb.
There Is one Of these stars In par
ticular that has attracted the atten-
ton Of astronomers. not only on ac-
count Of its great size, but also Its
enormous distance from our solar sys-
tenn. This is the star Arcturus. To
have some conception Of the almost In
conceivable distance that separates 1t
from us the astronomical standard of
measuring distance must be compre-
hended. Now. light does not come
from a luminous body instantaneously
to our eyes. 1t takes time to come.
because it is wave motion In
medium. The velocity Of light as
most recently determined is about
$4,000 miles a second. Multiply this
by the number Of seconds In q year
and we have distance known in as
tronomy as a light year. Therefore
when a star is, say, six trillion miles
away we say it is one light year on.
which means that the light from the
star takes one year to reach US. 1t
may be Of some interest to know that
there is no fixed star less than ten
light years away, or sixty trillion
miles. This is the one known as Alpha
Centauri. Most of the stars are much
farther even than that. Arcturus being
the farthest one measured to date.
Arcturus is thought to be at least
a hundred times larger than the sun
in diameter. That would make 1t
10000 times larger in surface, or the
dimension that is ordinarily compared.
BY means OF the photometer its bright
ness has been determined to be GOO
times that Of the sun. 1t is the fourth
brightest star in all the heavens. Siri-
us. the dog star. being first In bright
ness. As regards the distance from
us, it has been found to be a little over
16O light years. or $50 trillion miles.
This distance. Of course. cannot be
conceived by mortal man, 1t Is so stu
pendous and amazing. However. one
can get a slight idea Of il by means Of
an everyday analogy. Think Of the
fastest express train going at the rate
Of 100 miles an hour toward such a
star and compute the time 1t would
take. 1t In found to be In round num-
| bers exactly 12O.OOO.OOO years! Now,
as We know that 1t has taken its light
so long to come to us and rs there are
a great many stars whose distance
has never been measured exactly. but
which have been computed to be ap.
proximately several million light years
away. We have absolute proof Of the
universe.
The elements composing the sun Arc
! turus are. peculiarly enough, very
nearly the same as our sun. As 1t Is
one Of the post wonderful and as.
founding things that a scientist can
tell what a star 50 far away Is com.
posed of, q small explanation Of the
modus operandi would not come amiss
here. 1t is done by means Of . small
| instrument known as the spectrOscOpe
which consists of glass prisms so ar
ranged as to split up the light falling
on them into its constituent parts
Now, every substance has the power
to cause a certain color or line In the
spectrOscope il 1t is in a luminous con
dition. so this instrument is simply
pointed at the star whose composition
is sought, and If any line is found that
corresponds to a substance that We
know about we assume that this sub
stance is found in the star examined.
Another interesting thing is the meth
cd pursued in determining the great
distance Of the stars. This II done
by determining their parallax or angle
made at the star between two rays
from the star striking Mt two differ
ent points in space. As the greatest
distance that We can measure or IN
this way and still ta.;e the angle Il
the diameter Of the earth's orbit. that
distance is invariably used. 1t Is al
most 2OO,OO0.OOO miles, but that. as !.
seen, is very small compared with thu
enormous distance Of the star. Now
the angle thus measured from Arc
turus is only two-hundredths OF q sec
ond! When 1t is remembered thai
there are 60 seconds in q minute, @
minutes in a degree and 800 degrees
in a circle. it is at once seen what I