Helena weekly herald. [volume] (Helena, Mont.) 1867-1900, 1881-02-03
No. II
HOW LONG WILL THE sun LAST?
Prof. c. A. Young Gives His Views on
The Future of the Universe.
From the Popular Science Monthly

From the Popular Science Monthly
How is the heat of the sun maintained?
How long has it lasted already? How long
will it continue? Are there any signs of in
crease or Of diminution After affirming that,
IN the present state of science, only some
what vague and unsatisfactory replies are
possible. Prot. Young holds that, so far as
observation goes, we can only say that the
outpOuring OF the solar heat, amazing as it is.
appears to have gone on unchanged through
all the centuries of human history The au-
thor thinks that there is some truth in each
OF the two theories which have been proposed
to account for the suns fire.
AS to the first, the impact of meteOric mat
ter, 1t is quite certain that solar heat is thus
produced; but the question is whether the
supply OF meteoric matter is sufficient to ac-
count for any great proportion of the whole.
After giving Sir William Thompson s calcula-
ton OF the amount of heat which would be
produced by each of the planets falling into
the sun from its present orbit, by which it
appears that Jupiter would maintain the
suns present expenditure of energy for 80
254 years, and Mercury for six years and 219
days, and that the collapse of all the planets
upon the sun would generate sufficient heat
to maintain its supply for nearly 10000 years.
and after estimating that matter equal to
only about one-hundreth part of the mass of
the earth, falling annually upon the solar
surface, would maintain it's radiation indef-
nltely, Prof Young thinks it improbable.
from astronomical reasons that any such
quantity OF matter can be supposed to reach
the sun. So large a quantity OF matter would
necessitate vastly greater quantity circulat-
ing around the sun, between it and the planet
Mercury. But if there were near the sun
meteorlc matter equaling for example the
mass OF the earth, it ought to produce an OBJ
servable effect on the motions of Mercury.
and no such effect has yet been detected
Astronomers therefore, failing to find a
1ull explanation OF the cause of solar energy
IN this hypothesis, have adopted second one,
which is, that the suns diameter is SLOWLY
contracting, and thegaseOus mass is gradually
iquerfying and becoming solid. The econclu-
sion is drawn that if this theory be correct.
here must come time when there will be
10 solar heat, as there has also been a time
when it began. How far forward is the end,
loW far backward is the beginning? New
,omb is authority for the statement that.
With its present radiation, the sun will shrink
o half IT'S present diameter in about 100000
ears. Reduced to this size and eight times
IS dense as now, it would cease to be mainly
all: Hence Newcomb assigns as the term
urlng which the sun can supply heat enough
support life on earth, as we know life, a
eriod of 100000 years
The writer somewhat more confdentially
asts his eye backward, and concludes that
ne sun cannot have been emitting heat at
ne present rate Of more than 1SOOO,OOO
ears If its heat has been generated in the
tanner described. If the sun has contracted
ON diameter even many times larger than
lat OF Neptune's orbit to it's present dimen-
ons as is probably true in the MAN, 1--WE
re mexorably shut up to the conclusion
lat the total life of the solar system, from
S birth to its death, is included in some
'ch space of time as 3O,000,OOO of years; no
asonable allowance for the fall OF meteoric
AFTER" etc, could raise it to 6O,OOO,OOO."
he possibility of collision with wandering
ars, and the suggestion of ways as yet un-
,ncelved OF for restoring wasted energy, are
lowed by the statement that "the present
der OF things appears to be limited in either
rectlon by terminal catastrophes which are
lied in clouds as yet impenetrable."