Evening star., 1950-02-27
Cosmic 'Firecruckers'
In Suns Atmosphere
Phenomenon Causes
Flares of Radiation
By Thomas r. Henry

BY Thomas r. Henry
Cosmic frecrackers burst in the suns
high atmosphere.
They cause great flares Of radiation
which can be detected as far away AZ
the earth.
This phenomenon, hitherto unknown
to science, has been observed by Bureau
of Standards scientists.
The sun, like the earth, is surrounded
by = thick blanket Of atmosphere. 1t is
about a million miles thick. It is COM
pletely invisible to the naked eye except
in brief moments Of total solar eclipse
when the wierd pearl-colored corona
appears.
Now it can be "seen," after fashion,
by the radio waves emitted by the fam
ing star.
The suns radiation covers the entire
spectrum from short X-rays through the
invisible ultraviolet, the short range OF
visible light, the longer invisible infra-
red and short and long radio waves.
Ordinarily all this radiation remains
about the same day after day. Variations
In heat, or infra-red, radiation, for ex-
ample, amount to only few per cent
through the year. Even so, they may have
very important effects on the earth's
weather. The visible light from the sun
hardly varies at all and day after day
there will be hardly any change in the
ultraviolet and radio wave radiation.
But the Bureau scientists at the Sterl-
ing, Va.Q laboratory have found that
there are sudden fare-ups in some mar
row wave bands of radio wave radiation
which last from a fraction OF second
to few seconds in which the intensity
Of these bands increases as much as
thousand-fold. From the length OF these
waves and various other considerations
1t is possible to deduce the region where
they originate.
The longer radiations showing the
enormous 1are-ups come from attitudes
in the suns atmosphere where 1t is very
close to complete vacuum-closer than
ever actually is achieved in any vacuum
tube. The longer the waves. in general,
the thinner the atmosphere where they
originate and the longer the f1are-ups
last Six meter wave flares, for example,
last from two to eight seconds. Half
meter wave flares last from three tenths
Of a second to a whole second.
Flare-ups of different wave lengths
do not appear simultaneously. There
seems to be no time relationship between
one and another. Thus it seems highly
improbable that they are due to ex-
ceptional conditions on the surface OF
the sun itself, such as explain other
changes in solar radiation.
One explanation which occurred to
DR.. Grote Reber and his associates was
that the flares were due to meteors, or
shooting stars, from outer space falling
into the suns atmosphere and burning
from friction with the thin atmosphere.
The heat might be sufficient to cause
such momentary outbursts OF radlo
energy During times OF meteor showers,
however, there is no increase in the
number of outbursts, so this explanation
now seems highly improbable.
Another possibility is that exploding
bombs of some sort are fred hundreos
of thousands of miles into the atmos-
phere from the surface of the sun itself.
If such is the case the phenomenon must
be very rare and not associated with
other solar disturbances.
For the present, DR.. Reber says, there
simply is no clue except that fire
crackers" of some sort are exploding now
and then in the suns high atmosphere.
There are short periods when tho
whole surface of the sun seems to be
highly disturbed. which results in simul-
taneous flare-ups of all sorts OF radla.
ton. This. however. is quite different
phenomenon, DR.. Reber says.
Different also is the radiation from
sun-spots, enormous black areas on the
suns surface which are believed to be
titanic whirlwinds in the low, thick
atmosphere. From these darkened areas
the radiation of visible light, ultraviolet
and infra-red is less than from the sur
rounding bright region. Enormously in
creased, however, is the output OF ultra
short waves of the radio spectrum.
especially those about ten centimeters in
length.
Below this the increase is so small as
to be hardly detachable. There apparent
ly is a considerable increase in longer
wave lengths but it is SO diffuse that 1t Is
difficult to detect.
It is as if there were an invisible bulns
of 10 centimeter waves covering SUM
spots, the Bureau scientists explain. II
the human eye were sensitive to wave
lengths in this region the bulbs could
be seen. This phenomenon has been in
vestigated especially by DR.. j. F. Dinesse.
French physicist who has been guest
worker at the Bureau OF Standards
station.