Evening star., 1953-02-20
Astronomers Measure
Invisible Radio Sturs
Waves Trovel Million Years
Before They Reoch Earth
By Thomas R. Henry

The mysterious, invisible radio stars
spots in the sky from which various
long-Wave radio wave emanations are
received-are being measured for the
first time by British and Australian
astronomers.
These broadcasts from the heavens,
they report, do not come from point
sources. such as a single star. but from
fairly extensive regions such as would
be occupied by galactic nebula, vast,
luminous gas and dust cloud. All are Of
about the same size. so the apparent
size determined by the astronomers may
give fair idea of the distance of the
radio wave sources from the earth.
The largest area found is reported in
the British journal, Nature, by DR.. B.
Y. Mills Of the Australian government
Division Of Radio Physics. 1t covers six
degrees of arc in the southern con-
Stellation CentauruS, where also are To-
Gated the stars nearest the sun.
Other Sources.
Other sources located in the southern
skies were in the consultations Taurus
and Virgo. These also covered about the
dimensions expected of a galactic neb-
ula. Within the areas there were great
variations in the amounts of radiation
output. The chief source, however.
always came from near the center. In
each case it may come from a now in
visible star, perhaps the remains of a
former Supernova which at one time
hared up with brilliance thousands of
times that Of the sun. This is known to
be the case with one point of radiation,
the so-called Crab nebula, which long
has been studied by astronomers.
OF particular interest is the report of
DR.. F. G. Smith Of Cambridge Univer-
Slty. England. One of the best known Of
the radio stars" is in the constellation
OF CygnuS, the Swan, in the northern
heavens. The apparent area covered,
however, is only about sixth that of
the Centaurus source, but the same sort
OF variations in intensity of radiation
are found. This proves beyond doubt,
DR.. Smith believes, that this particular
radio star lies far beyond the limits
of the Milky Way galaxy and that the
radio waves coming from it travel for
at least a million years through space
before they can be detected by receivers
on earth. No island universe can be
associated with the spot, however.
X
Hunt for Oil Fields.
The American petroleum industry
spends about a billion dollars year
hunting for new fields.
Henceforth, it will look for uranium.
raw material of atomic bombs, wherever
it looks for petroleum. This has Just
been announced by the Society of Ex-
ploration GeophySiciStS, one of the
member societies Of the American Geo.
logical Institute. The plan has been
developed at the request of the Atomic
Energy Commission and now is being
presented to all the oil companies.
One of the major obstacles to dis
covering new supplies of the basic ra-
dioactive elements, uranium and tho
rum, Is the limited range of detection
instruments. Six inches of earth over
a uranium deposit, for example, cuts
in half the chances that it ever will be
discovered. There is only thouSandth
as much chance if there is four feet Of
soil on top of the radioactive deposit.
Oil-industry explorers drill more than
1000 shallow test holes every day in
holes average IS to 100 feet in depth.
Simple checking of the material exca-
vated from these holes for radioactivity
by special follow-up crews, it is believed.
will mean the checking of thousands Of
square miles for buried uranium. It
also is proposed that similar checks be
made on the material drilled out of
the first 500 feet of the thousand or
more oil wells opened each week.
Aid From Companies.
The oil companies are being urged
to provide all their explorers with'radi-
alton detector devices which they can
use while they hunt oil, often on foot
in remote and very inaccessible areas.
BY this means. it is believed, the
available amounts of radioactive ele-
mentS may be vastly increased. since
it is quite unlikely that all deposits
crop out on the earth's surface. They
may be distributed quite generally
through the whole crust of the earth,
down to depths of thousands of feet.