NAVY
USES MOON IN A RADIO RELAY
Applies New System to Send Photo and Notes
Between Washington and Hawaii
Special
to The New York Times.
WASHINGTON, Jan. 28 – A picture of an aircraft carrier and an
exchange of messages between two admirals were flashed between
Washington and Hawaii today
– by way of
the moon.
For the first time the Navy gave a public demonstration of the
capabilities of a new communications system, which uses the moon as a
reflector for radio signals.
The system promises to open a new channel in intercontinental radio
communications
– a channel
that is resistant to jamming by nature or by enemy. The system grew out
of a discovery by the Naval Research Laboratory in 1951 that the moon
could be used for bouncing radio signals between two points on earth.
For its “pilot” moon-relay circuit, the Navy has
set up a link between Washington and Hawaii.
To show the capabilities of the system, the Navy transmitted radio
facsimile pictures of the carrier Hancock
today. On the flight deck of
the carrier were a group of sailors spelling out “Moon
Relay.”
By teletype, messages were exchanged between Admiral Arleigh A. Burke,
Chief of Naval Operations, and Admiral Herbert G. Hopwood, Commander in
Chief of the Pacific Fleet, extolling this advance in communications.
The radio messages were transmitted by two large parabolic antennas,
eighty-four feet in diameter, situated in Annapolis, Md., and Opana,
Hawaii. The signals were received some two-and-a-half seconds
later, after making the 480,000-mile trip to the moon and back
– on similar
antennas in Cheltenham, Md., and Wahiawa, Hawaii.
Because the system operates in the ultra-high frequency range around
400 megacycles, it can help relieve the over-crowding on the lower
frequency bands now used for long-range communications.
Since these ultra-high frequencies are not disturbed by ionospheric
disruptions, the system will not be subject to
“blackouts” during geomagnetic storms. Furthermore,
the system can be jammed only by an enemy placing his signals between
the moon and the receiving and transmitting stations.
The principal disadvantage of the system is that messages can be
transmitted only so long as the moon is within sight of both the
transmitting and receiving stations. For the Washington-Hawaii link,
this time varies from a few hours to twelve hours.
Although the system is still under “operational
evaluation,” it has already been used for handling
“operational” messages during periods when solar
disturbances have disrupted conventional radio communications.
Article
from The New York Times, Friday, 29 Jan 1960, page 6.
See
also:
- Today in
Science History event description for moon radio relay on 28 Jan 1960.
