Evening star., 1935-04-09

The core of the sun consists Of
material which weighs approximately
IL, 100000 tons a cubic inch.
This is the hypothesis put forward
by Prof. Georges Gamow of the Len
ingrad Academy Of Sciences, now q
visiting professor at George Wash
ington University, to solve two of
the fundamental mysteries of ma
ture-how the sun has remained so
hot for a couple Of billion years
without burning to a cinder and how
the elements were formed.
1t is somewhat more than an
hypothesis. DR.. Gamow reaches his
conclusions from consideration of the
normal behavior of atoms in a mass
the size Of a star. He is one Of the
foremost living authorities on atomic
structure. Here is how it works:
The interior Of such an enormous
spherical body as the sun is sub
jected to tremendous pressure. due
to the gravitational pull on the ma
terials above it. This pressure will
contract it and, in this process, very
high temperatures will be caused.
According to Prof. Gamow's calcu-
lations they would run as high as
100000 degrees centigrade.
What would happen to matter sub
jected to such high temperature?
First, Gamow shows. it would break
up all molecules into their con-
stituent atoms. Then it would "com-
pletely ionize" all the atoms. That
Is, it would strip off all the light
outer electrons revolving around the
atomic nuclei. The result would be
that the matter in the vast depths
of the sun would be composed of two
gases, unknown on earth. One would
be electron gas, composed entirely
of free electrons. The other would
be nuclear gas, composed entirely Of
stripped nuclei. Both Of these would
behave very much like the Ideal
gases" of physics. The nuclear gas
would be hundreds of times heavier
than the electron gas, but only about
flftieth of the quantity. An atom
has only one nucleus, but there may
be from l to 90 outer electrons, de-
pending upon the element. Actually,
says Prof. Gamow, the effect Of the
nuclear gas in the results that follow
may be discounted altogether, since
there is relatively so little of it.
So the interior Of the sun can be
considered as composed primarily of
this light electron gas. Once it Is
formed it sets up a pressure in all
directions. The gravitational pres
sure of the outer layers-constituting
by far the greater part Of the star
continues. Thus there are two enor-
nous pressures against one another.
One of three things can happen.
These pressures may be in equili-
brium, in which case the stellar body
will remain unchanged. The outward
pressure of the electron gas may be
greater than the inward pressure of
gravitation, in which case the star
will expand, grow cooler in the proc
ess of expansion, undergo the process
Of reformation of atoms and mole
cules and perhaps end eventually as
dead star. But the gravitational
pressure inward may exceed the gas
pressure outward. In this case the
free electrons and nuclei will be
pushed closer and closer together. But
they will not lose their free status
and the nature of the substance will
remain essentially that of an ideal
gas.
Now, in temperatures such as are
found on earth the distances between
atomic nuclei and the free electrons
relatively are very great. There are
billions of atoms in the point Of
pin. But every one of them can be
compared to o solar system and, rela-