Evening star., 1954-12-27
Sun Seen Exploding :
LIN 5 Billion Years
Prediction Is Made
BY Gnmow, CIV Professor
BY Thomos r. Henry


The sun will explode--in about 8
billion years.
This is the prediction Of DR.. Georges
Gamow, professor Of theoretical phys
les at George washington University.
in the Christmas lectures of the Phil
osophical Society of Washington.
Every 500 years or so some star in
the hundred billion star Milky Way gall
axy, of which the solar system is part.
blows up and for few days or weeks
Is the brightest star in the heavens.
The Star Of Bethlehem may have rep
resented such an explosion.
But, as DR.. Gamow says, these explo-
Sions are not by pure chance, as was
supposed a few years ago. They hap
pen only when a star burns up all
its fuel-for the most part the ele-
mental gas hydrogen. Then 1t COLI
lapses. An exploding star is more
like the collapse of burning build
ing than the explosion of tank OF
gasoline. There is no possibility that
such q collapse will take place while
any fuel is left.
Sun Burns Slowly.
The sun, DR.. Gamow said, is burning
its hydrogen very slowly in heat-pro-
ducing processes somewhat similar to
that which now is the basis of the
hydrogen bomb. The extreme heat Of
the sun, he pointed out. leads to the
misconception that its fires must be
very hot Actually. the fire is so low
that, If it were on the earth, 1t would
require 10 months to boil pot Of
coffee over 1t.
The suns heat today is the accumu-.
lation Of heat over the past five billion
years, since the universe was created.
which has not been able to escape as
radiation due to the enormous size
of the body. He cites the analogy of
the humming bird, smallest of living
creatures, and the elephant. The for
n1er produces day after day of its short
life so times as much body heat as
the elephant. Because of its small size
1t Is able to get rid of most Of 1t. II
the elephant produced the same
amount. most of which it could not
"radiate," it would roast to death in
short time. This depends on the
fact that the volume OF a cubical or
spherical object always increases faster
than the surface area. Heat produce
ton is by volume, in cubic inches. Heat
only escapes by surface area, in square
inches.
Lot Of Fuel Left.
The sun is quite average star among
its hundred billion companions. A few
are burning their hydrogen much faster.
and will 60 up in smoke sooner. Some
are consuming their fuel much more
slowly and can be expected greatly to
outlive the sun. The amount of hydro
gen available has been calculated. It Is
enough to last from five to seven billion
years at the rate at which 1t now is
being burned.
It now is about 400 years since the
last great star explosion, or super-nova,
was observed in the Milky Way galaxy
and. by the laws of chance. it is about
time for another to appear. This may.
of course, have happened long since, but
the event would be unknown on earth.
The first such phenomenon recorded by
astronomers was about 1000 years
ago--but 1t happened so far, away in
space that the light of the explosion
required $4,000 years to reach the earth.
The site of this explosion. recorded by
Chinese astronomers. is now one of the
most interesting objects In the sky
the so-called "crab nebula." This lu-
minous patch, said DR.. Gamow, is the
smoke" from the explosion. which is
expanding at the approximate rate Of
1000 miles second. Photographs taken
at 10-year intervals show that its size
is increasing. The remnants Of the star
which exploded no longer are visible.
Such an explosion presumably means
the death Of star. There is no known
mechanism by which It's heat and light
can be restored.