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November 1961 Radio-Electronics
 [Table of Contents]
Wax nostalgic about and learn from the history of early electronics.
See articles from Radio-Electronics,
published 1930-1988. All copyrights hereby acknowledged.
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As far as I know, Radio-Electronics magazine editor Hugo Gernsback's
fear that intergalactic signals (not from alien life forms) might someday interfere
with terrestrial communications has not been a problem. His primary concern is if
something like a supernova occurs close enough to Earth to emit sufficient energy
in our communications bands to disrupt or even completely prevent radio operation.
Such a scenario is possible, if not improbable. If you want to call it good news,
the fact is astronomers have so thoroughly scanned, analyzed, and cataloged the
heavens that if there was a star on the verge of going supernova, we would know
about it. Even if such an occurrence is imminent but the star has not been directly
observed because the electromagnetic energy has not yet reached us, signs of the
event would be detectable - like a
disturbance in
the force along its path leading to Earth. Whilst on the subject of novae, keep
your eye peeled for news of the periodic nova that is star
T Coronae Borealis in the constellation Corona Borealis. If you have a telescope
or even good binoculars, be sure to take a peek at the
M13 globular cluster in Hercules,
and the M57 (the Ring Nebula)
in Lyra.
Our Radio Communications Threatened?
 ... Nearby Exploding Stars Hold Vast Electronic
Dangers ...
Since the advent of radio astronomy in 1931, we have learned that our entire
universe abounds with an incredible number of radio sources - stellar radio transmitters
- which continuously emit radio energy in every direction simultaneously. Every
star, our own sun, even some of our planets, are active sources of radio energy.
In addition, all the stars and our sun emit vast amounts of X-rays.
Even such puny man-made "suns" as our hydrogen bombs emit a large amount of energy
in a ten-millionth of a second, in the form of light, X-rays, gamma rays and neutrons,
causing a number of electromagnetic and other effects. As Dr. I. Maddock, chief
of the Field Experiments Division of the United Kingdom Atomic Energy Authority,
recently pointed out, in a nuclear explosion seven-tenths of the entire energy is
dissipated in the form of X-rays.
What about the stellar explosions - the novae and super-novae - that occur periodically
in the universe? In our own galaxy (the Milky Way) supernovae occur approximately
every 150 years. They act very much like our own atomic explosions. Their effects,
too, have been studied by radio astronomy. For instance, one of them, the famous
Crab Nebula, believed to be the remains of the supernova which exploded A.D. 1054,
is even today a most powerful radio source. That explosion still continues - the
nebula still expands at the rate of 70,000,000 miles daily. It is, however, 4,100
light-years distant.
What would happen if a supernova exploded in our vicinity, say from only 9 to
16 light-years distant?
This possibility was recently explored at length by C. M. Cade, chief scientist
of Kelvin Hughes, Ltd., a British concern.
There are only three potential supernovae in our vicinity: they are known as
the brilliant Sirius, 9 light-years away; Procyon, 11, and Altair 16 light-years
distant. If anyone of these should explode and become a supernova, the effect on
our radio communication system might be disastrous. According to Cade, with a supernova
at 4 light-years distant, all high-frequency, vhf and uhf systems would cease to
operate due to the titantic interference set up. The super-nova emission would completely
obliterate most short waves, radar, TV transmission.
It is possible that the longer broadcast waves might not be affected so severely,
depending upon the distance of the supernova from our earth. It should be noted
here that 1 light-year measures 6,000,000,000,000 (6 trillion) miles, thus the nearest
supernova would be 54,000,000,000,000 (54 trillion) miles distant.
The disruption of most radio communication would not be total for 24 hours a
day. It would occur only in direct line of sight with the supernova, i.e., when
it is above the horizon. At supernova "night," perhaps there could be communication
between centers turned away from the exploding star.
How long would the radio chaos on earth last after the supernova exploded? Cade
believes at least 1 year. This is his theoretical guess - it might be much shorter
or longer, all depending on the size and distance of the supernova. Strong radio
interference would last for many years.
Let us now make some further speculations on aspects on which Cade did not comment.
There is always a remote possibility that two suns could collide in our vicinity.
When such a celestial explosion does occur - let us say at 2 light-years - it
would seem likely that many receiving instruments on earth would be put out of commission.
The density of the electromagnetic flux would be so intense, so enormous that transistors
and other delicate components would be destroyed instantly.
What the electromagnetic saturation of the supernova will do to the earth's magnetic
field can only be surmised. Just as the far weaker solar magnetic storms often silence
nearly all trans-Atlantic cables and some long telegraph and telephone lines, so
the supernova's electromagnetic power field probably will burn out cables and telephone
gear and instruments. It will be a world-wide electronic devastation.
The havoc on earth will be less as the distance of the supernova increases. At
100 light-years, the damage on earth will be very much less.
We have had one brush with a nova since radio came into use. This was in 1944
when radio interference occurred from a nova (probably the Omega Nebula) in the
constellation Sagittarius, 3,000 light-years distant. It seriously interfered when
the Allies during World War II attempted to locate V-2 rockets with long-range radar.
If such powerful interference could occur with a supernova 3,000 light-years away,
one can visualize the havoc created at a distance of only 2 light-years.
What influence will a comparatively close supernova have on life itself? We already
know that powerful short waves do affect humans under certain conditions. They can
even be lethal.* That the supernova waves - though incomparably more powerful -
will prove deadly seems improbable, but the possibility exists, even if their potentialities
are not known. A simple protective measure, however, would seem possible: A thin
metal wire netting enveloping humans would conduct the waves to earth - short-circuiting
them effectively. What about the much more dangerous X-rays, also generated abundantly
by a supernova? Our atmosphere seems to shield us from them most efficiently. Our
own sun, only 8 light-minutes away, is known to be a very powerful X-ray generator,
yet we do not suffer from its effects.
Unfortunately, so far we do not know when a neighboring star might explode. Perhaps
now that we know the inherent danger of comparatively near stars, our astronomers
will watch them more closely to obtain clues as to when they will become supernovae.
In time this may be possible.
This brings to mind the question of the dinosaurs and their sudden disappearance
from the earth some 70,000,000 years ago. No satisfactory reason has ever been given
for their eradication.
Is it possible that 70,000,000 years ago they were killed by short waves emitted
from a close supernova? Perhaps we shall know more about this in the future. - H.C.
*See "Radio Power," Radio-Electronics, July 1961.
Posted July 15, 2024
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