Evening star. [volume] (Washington, D.C.) 1854-1972, 1929-03-23
Smithsonian Flag Structure
to Serve for Studies of
Solar Radiation.
ATMOSPHERIC OZONE
B0MBARDED BY SUN
Northern Hemisphere Phenomenon
and Human Body's Radiation
to Get Attention.
BY THOMAS r. HENRY.


INTO laboratory for studies of solar
'adiation under direction of DR.. Charlie:
G. Abbot. secretary of the institution
Work of eouipping the tower with
an elevator now is under way. Below
The solar laboratory. Offices will be pro.
vlded for other Smithsonian scientists
Inc top OF the tower commands ar
undlsturbed sweep of the sky, and pro.
Woes an excellent location for carrying
out part OF a new research project
10 be undertaken by the Smithsonian
In an effort to determine the effect oil
sunlight on the growth and health OF
plants, animals and children.
rms study partly has been provided
for by $4,000 grant from the Ma.
tlonal Research Corporation and will
be undertaken by DR.. Abbot and his
assistants. The extent to which this
work vii be carried on in the new labo-
ratory. DR.. Abbot said. is undetermined
1t may be feasible to make only prelim
mary Investigations here and then trans.
fer them to Smithsonian station in
the Southwest. where the sky is clear
for long, uninterrupted intervals. This
has been found necessary in solar OBJ
Servation projects in the past which
nave been started at the astro- physical
observatory and then transferred as
made under better observing conditions
became apparent
Great Exactitude Required.
Due to the experience of the Smith
Sonlan staff and to some of the mar
velously precise instruments perfected
by Dr. Abbot. the Smithsonian is In a
unique position In project requiring
great eXactitude. The results of two
projects largely based on such measure
ments have just been announced by
the institution.
The first is study of atmospheric
ozone. conducted by Frederick E. Fowle
of the staff of the astrophysical OBJ
servatory. and the second of the radia :
ton OF the human body by l.. B. AL
drich.
The sun at certain times is lombard
ing the outer atmosphere of the earth
in the northern hemisphere with cleo
trified particles shot outward into space
at such tremendous velocities that they
escape the suns gravitational field.
This Is conclusion suggested by the
study of atmospheric ozone by Mr.
Fowle.
Ozone is a colorless gas. special
arrangement OF oxygen atoms. which
ordinarily is formed by the passage OF
electricity through oxygen. 1t has a
pungent. chlorine like odor, which
sometimes is noted after an electrical
storm. Popularity the term often is
confused with oxygen.
Layer In Upper Air.
In the upper atmosphere, approXi-
mately 40 kilometers above sea level,
there is layer of this gas which long
has been of interest to meteorologists
because of its absorption of radiation
coming to the earth from the sun.
Without this layer, it is likely. the pres
ent forms of life could not exist on
earth. The layer is believed to be due
to absorption by the atmosphere of
certain wavelengths of the solar spec
trum-particularly considerable part
of the ultra violet. If these extremely
short wave lengths Of light bombarded
the earth without any screen the re-
suits probably would be disastrous. al
though problema teal. Ultra violet light
is beneficial to life only in limited and
carefully balanced quantities. This ball
ance has been taken care OF by nature.
The fullest possible knowledge OF the
CduoSc dIIu GIlCttSo Va Jlllo dtuiOcRA1CAiN
layer is of special significance IN the
Smithsonian studies of the effects OF
variations OF solar radiation on weather.
A basic factor in these studies is the
determination of the amount of radia-
ton which strikes the outer atmosphere
of the earth and its progressive reduc-
ton at lower levels due to absorption
by various mediums.
TAUJlofc cfyfHu lie Ho cod nkncorHa -
tons taken for approximately 1000 days
at the Smithsonian observatories at
Harqua Hala and Table Mountain in
the Southwest, Montezume, Chile, and
Mount Brukkaros in South Africa.
Certain wave lengths of ultraviolet
light radiation passing through the at
mosphere. Mr.. Fowle concludes, GER
tainly would produce ozone, but these
could not penetrate lower than about
40 kilometers above the earth's surface.
Following them in the solar spectrum
come other wave lengths, which destroy
ozone. but which penetrate deeper, wip-
ing out the ozone in their path. Thus
the ozone layer due to the ultraviolet
absorption almost of necessity must be
at a very high altitude.
Evidence of Lower Layer
But in the Northern Hemisphere
there is evidence of lower ozone layer
which consequently must be due to
something else. Nine. Curie, the CO.
discoverer of radium, Mr.. Fowle points
out, has shown that the passage Of
alpha particles from radium salts
change oxygen into ozone. Other in
vestigators have indicated the great
that electrified particles
from disturbed areas on the sun gain
such velocities that they are projected
into space. Hitherto there has been no
evidence as to what became of them.
Previous efforts have been to estab-
lish the identity of what appeared to be
the two ozone layers and to explain 1t all
as due to the light wave absorption. Mr..
FoWle has worked out corlela BON be-
tween one of them and certain sun-spot
phenomena observed on the sun.
The first layer. he concludes. does not
vary with the sun-Spot numbers, Is To-
Gated over both the Northern and
Southern Hemispheres, and shows a
progressive and regular variation in
amount with the seasons. 1t reaches its
maximum in the Spring and its mini
mum in the Autumn in both hemi-
spheres. This he explains as possibly
due to the seasonal change of the earth's
position in respect to the sun and the
scattering of ultra violet light waves by
the greater extent of solar corona.
The second layer is present only in
the Northern Hemisphere, does not vary
with the seasons, and varies markedly
with the sun-spot periods. At the only
sun-spot minimum period this layer
practically disappears. The electrical
particles. Mr. FoWle points out. appar-
entity are so polarized that they are
drawn to the arth's Northrn Henri
sphere.
The study of body radiation conducted
by Mr. Aldrich is expected to prove of
special value in such matters as the
design of school rooms where seats can
be arranged and ventilation provided
with These highly technical findings in
mind. At a distance of 30 centimeters.
Mr.. Aldrich found. no heating effect of
the presence Of the human body could
be detected In still air.