Evening star., 1938-11-08
1W-FoId Hotter Sun
Some Day Will Melt
Earth, Says Scientist
9. w. U. Astronomers
Prediction Overturns
Previous Beliefs


A hundred-fold hotter sun, in
whose glare earth and everything on
it will melt like a cube of ice, was
predicted last night by DR.. Georges
Gamow, professor of theoretical
physics at George Washington Uni
versity.
This dire end of the planet is a
long time off, he fastened to add,
and although the suns heat is in
creasing every day. the climate is
not likely to be notably affected dur
ing the next few million years when
human life can be expected to con-
tinue on earth.
DR.. GamoW predictions, based on
new theory of the source of the
suns heat supply, turn completely
upside down most previous pro-
nouncements of astronomers that
the sun is constantly using up its
to get colder and colder from
now on.
The most likely source of solar
heat, DR.. Gamow said, is the forma-
ton of the Sungas, helium, out of
the mother stuff of all creation, the
light gas hydrogen. In some way
this is going on constantly in the
tremendous temperatures of the
suns interior.
Process Is ProblematicaI.
Just how it happens is problemati-
cal. On earth atomic tranforma-
tions are brought about by shooting
hydrogen atoms at other elements
with forces Of several millions of
volts behind them, so that they move
with almost the speed of light. In
! the gaseous substance Of the sun,
DR.. GamoW said, the place of the
high voltage is taken by the enor-
nous temperatures, approaching
close to 10000 900 degrees centigrade
towards the stars center.
Heat, after all, depends on the
movement of elementary particles,
atoms and molecules, and the faster
they move the hotter it Is. Anything
in a temperature of 100000 de-
grees would be moving almost as
fast as light. Suppose two atoms of
heavy hydrogen bump together at
such speeds and stick to each other.
The result would be one atom of
helium which weighs almost. but not
quite as much as the double weight
atoms of the light gas.
Sun Caught in Vicious Circle.
There is certain amount of
weight, or mass, to be accounted for
when this transformation has been
made. According to the Einstein
predictions mass and energy are
equivalent, being merely two differ
ent aspects of the same thing. Ac-
tually, says DR.. Gamow, the lost
mass has become heat. The faster
the transformation goes on the hot
ter the sun gets, and the hotter the
sun the greater the speeds of the
flying atoms and the faster the rate
of transformation. So there is set
up vicious circle of increasing heat.
A more logical mechanism for
the helium formation. DR.. GamoW
said, is from the collision of hydro
gen with lithium atoms, hthium be-
ing the next lightest substance in
the atomic table. In the collision
of two such atoms an atom of helium
is knocked loose and another part
of the original mass appears as
heat He has calculated several
other atomic collision possibilities
from which helium and heat would
result.
Altogether, he said. it is possible
in this way to calculate that the
sun has sufficient Matchmaking ma
terial to keep it going for 100000
900 900 900 years, and man need not
worry about what will happen after
that.
Sun Began as Hydrogen.
In the beginning, according to his
calculations, the sun was composed
almost altogether of hydrogen. In
three or four billions of years this
has been transformed into helium
at such rate that now only about
so per cent of the suns mass is
composed of this lightest and SIM
plest of gases. This is confirmed by
spectroscopic observations. AS the
hydrogen content is depleted, Dr.
Gamow said, a star becomes brighter
and brighter. Finally all the hydro
gen is used up. Then, said Prof.
Gamow, the star must begin to
contract in size, and finally come
to very dense state, with its
luminosity constantly declining
Such stars are we'll known to as
tronomers. the so-called white
dWarfs," due to their small luminos-
ity and, because of the extremely
small radius, very high surface tenn
perature. The first discovered star
of this type was the companion
star of Sirius, now the brightest star
in the sky, which has an average
density of 100000 times the same
volume of water Another star of
this kind has about 1000 900 times
the density of an equal volume of
water.
THE white dwarfs still have some
radiation, which is why they can
be seen. They evidently have not
yet reached the final state of con-
traction in which they should use
all radiative properties. This state
of an absolutely dark and cold body
of very high density awaits also
our sun after It's luminosity passes
over the maximum possible from
the transformation Of hydrogen into