Amateurs are aiding science's greatest international
effort
By Mike Bienstock
Associate Editor
Scientists are in the midst of a concerted assault on
the secrets of Mother Earth the likes of which have never
before been attempted. The International Geophysical Year
will not end until December 31, but by that time some 5000
scientists of 67 nations will have accumulated enough data
to keep electronic computers clacking for years. The results,
when they finally become known, are expected to increase
the knowledge of the planet we inhabit by a thousandfold.
We Earthlings are compressed between two oceans - the mass
of atmosphere extending above us for 200 miles or more,
and the mass of water, plumbed to a depth of more than 35,000
feet. We are familiar with just the fringes of these oceans,
and even there the acquaintance is only nodding. Of the
land area of our world, our deepest oil well has only scratched
the surface. We barely have touched the edges of Antarctica.
It has been said that we know more about the stars, since
we are able to stand off and take a good look at them, while
here on Earth, so close to our subject, we grow cross-eyed
trying to view the "big picture." Actually, it is suspected
that we are off several hundred feet in our measurement
of distances between continents.
Fields of Research. The IGY has planned,
since 1954, to concentrate in one 18-month period investigation
into the fields of aurora and airglow, cosmic rays, geomagnetism,
glaciology, gravity, ionospherics, longitude and latitude,
meteorology, oceanography, rocketry, satellites, seismology,
solar activity and "World Days." The latter are periods
of all-out concentration on one subject when there is sufficient
warning of some unusual event in that field, for example,
sunspot activity.
Interior of aircraft
instrumented for ionospheric research. The instrument in
the foreground measures the heights of the layers in the
ionosphere using vertical incidence pulses.
Most of the effort is being devoted to the atmosphere
and the electrical phenomena which occur there.
Besides the professional scientists giving all their
energies to IGY, thousands of amateurs volunteer time as
observers to aid the effort. Project Moonbeam, organized
to use the abilities of radio amateurs and others, has been
vital in tracking the earth satellites, despite the fact
that the observers were forced to make a quick switch from
108 mc. (the frequency originally decided upon) to 20 and
40 mc., which the Soviet Sputniks employed.
Tracking Systems. The primary system
for tracking satellites by radio and recording their telemetered
signals is the "picket fence" of Minitrack stations manned
by professionals. The supporting Moonbeam program uses a
simpler Mark II Minitrack system as well as a different
setup, Microlock. Both use phase comparison techniques,
and the equipment is simple enough to be built by amateurs.
Measuring telemetered
data from rockets in flight at an installation in Manitoba,
Canada. At the far left is a telemetry recorder which takes
data from airborne rockets; in the center is the main recorder
which puts data on tape; the ballistic camera master control
is at the right.
In addition to radio tracking, visual and photographic observations
are used by amateur groups.
While the satellites thrown into orbit by the Soviets
and the United States are expected to reveal an astonishing
amount of information in regard to the nature of the upper
atmosphere, cosmic rays, auroras and the ionosphere, other
devices mainly dependent on electronics are already contributing
extensive data to the effort.
Scanning photoelectric
photometer selects and measures the intensity of light too
faint for the human eye and records its changes. This airglow
camera is at Fritz Peak, Colorado.
For instance, radiotelescopes around the world are concentrating
their antennas on the sun. Sunspots seem to be related to
tremendous explosions on the sun that shoot out streams
of charged particles, ultraviolet light and x-rays. Immediately
after such "storms" on the sun, violent atmospheric disturbances
occur. Very quickly short-wave communications fade, auroras
burst forth in the northern and southern skies, cosmic ray
intensity increases and the magnetic field of the earth
shifts rapidly.
Strangely enough, not all sun "storms" cause these upheavals
on earth. One of the things IGY is attempting to discover
is the reason for this.
All during IGY, when such storms are detected, the world
warning center at Fort Belvoir, Va., will be sending out
alerts for special "World Days," during which scientists
concentrate all of their energies on measuring whatever
disturbances may occur. Up go "rockoons" (rockets launched
from balloons) and Aerobee rockets fitted with delicate
instruments to measure the intensities of x-rays, cosmic
rays, ultraviolet radiation and such. A close check on the
"shifting" of the E and F layers of the ionosphere is kept
to determine the relationship of sunspots to such movements.
Already a new layer of ionization, 12 miles below the lowest
point, has been discovered. It was learned that this new
layer was caused by solar x-ray emission associated with
solar flares. Meanwhile, the normal layers of ionization,
E and F, seem to remain stationary during a blackout, contrary
to former opinion. It may be, therefore, that radio blackouts
are caused by signal absorption in the newly discovered
layer.
Radio transmitter with
a 4000-mile range is part of the electronic instrumentation
of the U.S. earth satellite.
Watch on the Mountain. A new instrument,
the recording photometer, keeps watch on Fritz Peak, Colorado,
to determine the change in the intensity of air-glow - a
light so faint we can barely see it. This phenomenon is
believed to come from some chemical reaction of oxygen,
sodium and other ions in the D layer, about 60 miles up,
and may be affected by solar storms.
Cosmic rays are getting the once-over for another reason:
they give us an important clue to the character of the earth's
magnetic field. Since they are charged particles, they are
deflected by the earth's magnetic lines of force. Near the
magnetic poles, where the lines are nearly vertical, there
is little deflection, and therefore a greater intensity
of cosmic radiation than along the magnetic equator, where
the lines are close to horizontal. About 100 stations around
the earth are measuring constantly the strength of cosmic
rays, using two delicate electronic instruments, a neutron
counter, sensitive to low-energy rays, and a meson "telescope,"
more sensitive to high-energy radiation. Collating the hundreds
of thousands of readings of these instruments, scientists
should be able to obtain a much better understanding of
the shape and intensity of the earth's magnetic field.
Also in the tiny "moon"
is a 48-channel encoder which receives and encodes data
from other satellite instruments for transmittal back to
the earth.
Another important study will be that of "whistlers,"
faint chirping and whistling noises discovered during the
First World War. Back in 1950 it was learned that these
noises are actually caused by low-frequency waves from lightning
discharges, which follow the earth's magnetic lines of force
from the point of origin, out into space, and back along
the lines to the opposite hemisphere.
A huge antenna has been erected across a ravine in Colorado
which is used to pick up these whistlers. A field station
nearby amplifies them and records them on tape for future
study. Another form of whistle is also being recorded there
- the "dawn chorus." These noises, reminiscent of the pipings
of frogs at dawn, are thought to be caused by streams of
hydrogen ions at the edge of the atmosphere. Study may be
able to correlate these noises with the intensity of solar
storms.
With the advent of the forward scatter technique, which
utilizes the ionosphere to bounce signals back to earth
hundreds of miles away, engineers are anxious to learn all
they can about this unreliable phenomenon so they can use
it more effectively.
The National Bureau of Standards has set up test transmitters
in South America to use the forward scatter technique across
the magnetic equator. It is suspected that this method will
be especially effective because the ionization layer theoretically
should line up with the magnetic lines of force, thus making
for more even scatter propagation. Again the radio amateurs
assist in the IGY program, since many of them listen for
these transmissions, especially in the western part of the
country and in Mexico, and send their reports to the Bureau
of Standards.
Auroras. Another important study is
that of auroras. These intensely beautiful phenomena are
believed to be set off by streams of hydrogen ions caused
by solar storms. The ions are thought to react with the
atoms of the upper atmosphere and make them glow like a
fluorescent lamp. Some scientists had thought that auroras
should occur simultaneously at both of the poles. This has
now been established as a fact. Amateur astronomers have
been recording the shape and intensity, as well as the angle
above the horizon, of auroras in the upper northern regions.
Concurrent investigations by meteorologists at the South
Pole made the confirming study.
It is believed that auroras occur in day-time, although
they can't be seen then. Therefore, observers near the auroral
zone use sensitive radars to try to pick up reflections
from the electron clouds which accompany auroras during
daylight hours.
Although the IGY program will end officially Dec. 31,
1958, a good many projects will continue in operation. As
a matter of fact, they may be prolonged indefinitely, especially
those that are fairly inexpensive to maintain.
World data centers are being planned in the United States,
the Soviet Union and other areas, in which digested results
of the observations will be filed for scientists. It is
not expected that such results will be put into usable form
before 1965, but after that date science textbooks may have
to be thoroughly rewritten because of IGY's results.