Evening star., 1925-01-12
SUN SPOTS VIEWED.
AS RADIO Factors
Electrical Disturbances on
Earth Are Attributed to
Solar Changes.
BY DR. z z. FREE.

1t has long been known that the
dark fiecks which occasionally appear
on the surface OF the sun-the So
called sun spots--are in reality vast
Hhirling storms like our terrestrial
cyclones, but SO vast that dozen
complete earths might be dropped
into the gaping vortex of some of the
more colossal of these solar whirI-
winds. Now II has been discovered
that the sun spots are not only tire
mendous material distur Dances; they
are also great magnets, containing
intense magnetic fields.
This conclusion results from the
long work OF DR.. George
Ellery Hale and his associates at the
great observatory OF the Carnegie Iu-i
stitution, at Mount Wilson, Calf BY
examining the light rays received
from these spots-for the spots are
not black, but are merely not 50
bright as the rest OF the suns sur,
face-Dr. Hale has been able TO show
that this light has been affected by
magnetism, just as light is affected
if it is produced here on earth be
tween the poles of a powerful electrc9
magnet.
Usually in Pairs.
Not only does this prove the spot,
to be the site of an Intense magnetic
field. but detailed examination of Il.
large number of sun spots has shown
that they usually occur in pairs. one
of the spots possessing a north mag
netic polarity, while the other has
the character of south magn netit'
pole. This behavior appears, too, to
be closely associated with the cyclR.
according to which the number of sun
spots Increases and decreases in T.
period Of IL years. "'
During one Of these solar-spot
cycles the spots will have their mag
netic polarites In one direction, say-
with the north magnetic pole at the
end of the spot toward the sun-S
north pole. At the time of suns spot
minimum this reverses. When the
spots begin, thereafter, to increase in
number, II is found that the spot posS
SesStng a north magnetic polarity IS
now the one toward the suns south
pole instead OF toward its north pole.!.
All this indicates a most compli-
Gated situation, probably related, DR.
Hale believes. to something that is
going on deep inside the sun. Whar
that something is it is not yet pos
sible even to guess.
There are, however, some facts a =
ready evident and which have much
interest for radio engineers. For ex
ample, the mere fact that the sun
spots are powerful magnets may be.
important TO US. All raOlO engineers
now agree that the magnetic and
electric condition Of the earth has
very important effects on radio trans
mission. Great disturbances on the
sun, including large and numerous
sun spots, have been observed to CO.
incide many times with the so-called. 4.
| magnetic storms" that put telegraph
lines out OF commission and disturb
radio all over the earth. It is one
the many remaining mysteries about
the sun.
May it not be possible that this re
current sun-spot cycle has its inJ
fluence on the radio? 1t is noticeable,
for example, that the Summer OF 1929
was unusually free of static. This
is also the year of minimum sun
spots, which means, we may suspect
the year of minimum magnetic dis.
turbance on Cor in) the sun.
Unfortunately we possess no accurS'
ate records of the prevalence OF static
| in past years or, indeed, of the course
TO year. It seems not impossible
| however. that less magnetic dis'i
| turbance on the sun may mean less
static here, or may affect in some
other way the nature of radio trans~.
mission on earth. DR.. Hale has proved
that the spots are great magnets.
Variable magnetic fields Of such great.
intensity can hardly be without their
electromagnetic effects at distances
so short, relatively, as that of the
sun from the earth.
Copyright, 1925, by Popular Radio, Inc .,