Evening star., 1951-04-09
Huge Radio I eIescope
May Widen knowledge
'EIectronic Ear to Intercept
Rudiutions From the Sun
By Thomos R. Henry


A 75-ton radio telescope is being con.
structed at the Naval Research Iabora-
tory here.
1t is dish-shaped metal reflector
about 500 feet in diameter, which could
be mistaken for radar apparatus. It Is
gigantic electronic ear designed to
intercept extremely short-wave radia-
tions from the sun, the stars. and
mysterious patches in space now known
as "hot spots"
The great slightly concave disk re-
hects these radiations, which then are
detected by extremely sensitive radio
receiving equipment. They actually are
recorded on moving strip of paper.
More than so Of these spots" now are
known. They are known as radio stars"
although each has many times the dia-
meter Of any stars. They are completely
invisible but retain fixed positions in
space. BY means of them, provided it
were possible to carry the necessary
heavy apparatus, ships might be directed
by celestial navigation in any weather
and in broad daylight.
There may be other practical applica-
tions Of this new radio astronomer" /"
but the primary purpose is extension of
the basic knowledge of the universe.
The times and types of radio ennis
sions from various heavenly bodies will
be studied and the findings eventually
may have bearings on weather fore
casting and radio communications.
Flaming Geysers Important.
Special object of Investigations will
be the great geysers of flaming hydrogen
which shoot out from the face of the
sun thousands of miles into space, and
it has been found, have considerable
effects on weather These emit special
wave lengths which can be intercepted
by the great mirror and whose changes
will give information on the speed with
which they rise from the solar surface
and also on their temperatures and
composition.
The nature of the invisible stars"
the hot spots of creation, has remained
up to the present almost complete
mystery.
Steel men are helping solve the mos
quito problems of northern forests.
They are stainless steel dummies,
dressed in wool sweaters and jenkins.
each filled with 100 pounds of water and
kept at a constant temperature of 96
degrees. They apparently attract the
voracious insects in the same way as do
real men, for which they are mistaken.
The results of various changes in con-
ditions to which the dummies are eX-
posed have Just been reported in Ma
ture, journal of the British Association
for the Advancement of Science, by DR..
A. w. A. Brown of the University Of
Western Ontario.
Water Attracts Mosquitoes.
At the air temperatures higher than
so F. twice as many mosquitoes were
attracted when the clothing was
soaked with water. When water was
mixed with carbon dioxide the effect
was no more than for normal wet
clothing. The attraction of clothing
soaked in human sweat was twice as
great as when water was used.
In one experiment carbon dioxide was
blown through the mouths Of the dunn
mics. The attraction of the body was
doubled and that of the head tripled.
Both ether and Illuminating gas were
found to be very attractive to the mos
quitoes. Chloroform was decidedly re-
pellent.
Only from fourth to tenth as many
insects alighted on white clothing as
on black. Light shades of red and blue
were much less attractive than black.
Satin was less attractive than nylon
and nylon itself considerable less than
cotton.
The experiments are expected to throw
considerable light on one Of the worst
nuisances of the northern forests and
of the sub-Arctic where the great hordes
of mosquitoes in summer often render
life almost uncomfortable. In case Of
future military operations they might
constitute a notable factor since the
best chemical repellents are only in
differently successful.