The Origin and Evolution of the Deep Space Network
NA SA’s system for communication with solar-system exploration
spacecraft began as a Cold War crash program, but iis evolution was
carefully planned from the starl
Thirty-four years ago, a single principal antenna, installed the
previous year (1958) on a crash basis in an isolated location of the
Mojave Desert of California, supported Pioneer 4, the first United
States spacecraft to escape the Earth’s gravitational pull and travel
toward another solar-system body, namely the Moon, the nearest
such body to Earth. 1 hat lone antenna, situated near the Goldstone
Dry Lake Bed within the Department of the Army’s Fort Irwin, would
become the cornerstone clf NASA’s Deep Space Network, a system
currently composed of 13 antennas of various designs and sizes that
collectively have the capability of continuously communicating with
spacecraft at distances ranging from high altitudes above the Earth
to the outer edge of the solar system.
When the Goldstone antenna was procured, however, NASA had
not yet come into being. It was instead the Department of Defense
that provided the funding for the procurement, fabrication, erection,
and testing of this antenna during a relatively short eight-month
period in 1958. The antenna, as well as the series of early lunar-
probe attempts of which Pioneer 4 was a part, was, as we shall
show, approved on a crash-program basis as one aspect of the Cold
War then raging between the United States and the Soviet Union. It
would not have been surprising if an antenna so hurriedly
manufactured and installed for a short-term goal would
subsequently abandoned when NASA began setting up a
have been
permanent
system for later lunar and planetary probes. The fact that it was
not was a reflection of careful planning by the procurer of the
Goldstone antenna, a group of engineers at the Jet Propulsion
laboratory (J Pi.), an Army facility in Pasadena, California, that
became a part of NASA in late 1958. The early evolution of the Deep
Space Network illustrates how a major communication system can
be firmly established through a combination of carefully chosen
initial elements, put in place during a period of limited time and
funding, arid later additions, installed as requirements become more
ciemanding and further resources (such as funding and cooperating
agencies) become available.
The Cold War origin of solar-system exploration
An official requirement for a system to communicate with
space probes developed for the first time on 7 March 1958, when
the Eisenhower Administration, through the Department of Defense’s
new Advanced Research Projects Agency, authorized a program of
five lunar-probe attempts, three by the Air Force and two by the
Army, all to be conducted within a year. The Administration publicly
characterized the program (shortly to be named Pioneer) as a
scientific project an effort “to determine our capability of
exploring space in the vicinity of the moon, to obtain useful data
concerning the moon, and provide a close Iook at the moon. ” Archival
records show, however that the major impetus for the program disapproval was a desire by many inside and outside of government to
find some quick means of restoring international prestige to the
United States, after the Soviet Union’s successful orbiting the
previous October of WJIDK the world’s first artificial satellite,
had shattered a widely-held percepticln of American technological
superiority.
In the six months between this event and Pioneer program
announcement, in fact, numerous proposals for immediate “Moon
shots” had been submitted to the Pentagon, and many cited the
perceived Soviet threat. one of the first institutions to do so was
JP1 . In a proposal entitled “Project Fled Socks” issued on 21 October
1957, the lab observed that the launching of Sputnik 1 ICNS than
three wcmks earlier “has had a tremendous impact on people
everywhere” and that it “has significance which is both technical
and political. ” The proposal stated that it was “immediately
imperative that the United States regain its stature in the eyes of
the world by producing a significant technological advance over the
Soviet Union.” Pointing out that all had “some fairly sophisticated
instrumentation and communication” capability that would allow it
to achieve a successful lunar flyby mission, the lab advocated that
the country “go to the moon instead of just going into orbit.”
JPL was not alone in perceiving a potential political benefit
deriving from a successful lunar mission. F{amo Wooldrige’s newly
formed Space Technology Laboratories (S1 L ), located in I os Angeles,
California, argued, in a proposal entitled “Project 13aker” issued on
27 January 1958, that an early lunar flight with a moderate payload
of scientific instruments could make a determination of conditions
on the Moon that would be valuable for planning later flights with
much heavier payloads that were certain to come within a few years.
The firm also suggested, however, that “Of greater national
importance may be the prestige of sencfing the first rocket to the
moon, with clear proof that it reached its objective. ”
Scientists and politicians, however, were initially not
enthusiastic about these and other lunar-probe proposals. The
director William Flickering recalled that members of the Office of
Defense Mobilization’s Scientific Advisory Committee (ODMSAC)
“were not sure that [the Red Socks proposal] was more of a stunt, as
it were, and were not really that enthusiastic about it from a
scientific point of view. ” Deputy Secretary of Defense Donald A.
Quarles testified before Congress in late November 1957 that he
found “no cause for national alarm” in the existence of the USSF1’s
Sputnik satellites and argued that the United States “must not be
talked into ‘hitting the moon with a rocket’ just to be first, unless
by doing so we stand to gain something of real scientific or military
significance. ” Eisenhower himself tolci colleagues that he would not
be drawn into a “pathetic race” with the Soviet Union, and he
characterized a lunar probe as “useless. ”
The views of the scientists and politicians regarding “Moon
shots” gradually changed, however, especially after the United
States’ first attempt to launch a satellite (Vanguard) on
1957 ended in spectacular failure--the explosion of the first stage
of the launch vehicle within seconds of liftoff was recorded on live
television. On 17 February 1958 the Space Science Panel of the new
President’s Scientific Advisory Committee (reorganized from the old.J-
OLMSAC) held a meeting in the Executive Office Eluilding (next to the
White House) at which panel member Herbert York announced, to
attending representatives from JPL and S-IL, that “it had been
decided to attempt a lunar mission with the objectives of: a. Making
contact with the moon as soon as possible, but with the limitation,
that the contact be of a type that has significance such that the
public can admire it. ” York further stated that the panel had
concluded, given the second objective, that “some kind of visual
reconnaissance” (e.g., a camera to take a picture of the back side of
the Moon) was the most significant experiment that a lunar vehicle
could carry. PSAC’S endorsement c)f an early lunar mission would
lead to the aforementioned Pioneer program authorization in late
March.
Supporting the Pioneer probes: S71 ‘s short-term approach
The
of launch
would trai
positions,
for withou
Pioneer program would require simultaneous development
vehicles, spacecraft, and ground-support stations that
lsrnit commands to the spacecraft, determine their
and receive data from thcm. The stations were important,
them no close-up photograph of the Moon could be
c] btaincd and, more fundamentally, no confirmation that tho
spacecraft were anywhere near the Moon was possible.
[Iut what kind of network of stations should be set. Should
it be cicsigneci solely to support the Pioneer program and its limited
objective of photographing the Moon? Or shou Id a more elaborato
system be constructed that would meet not only the requirements of
the pioneer program but also the anticipated needs of future
programs not yet authorized?
STL, initially under the leadership of Frank Lehan, had little
choice but to undertake the short-term approach. Because of the
more ready availability of their iaunch vehicles (1 hor IRF3M and
Vanguard upper stages, the. three Air Force probes would be launched
first, beginning in nlid-August 1958. l-his situation wouid allow the
Air Force and STL the initial opportunity to reap the glory of a
successful first lunar mission, but it allowed the latter less than
five months to set up a network of ground-support stations.
By necessity, the antennas used at the two principal stations
had to be already erected or at least manufactured, and their
locations were governed by the roles they would play in
communicating with the lunar probes while they were in the vicinity
of the Moon. For example, a 60-ft-diameter parabolic antenna with a
transmitter a modification of the l“LM-18 antenna that Foundation,
Inc., was currently manufacturing for we in the forthcoming Air
Force Discoverer reconnaissance-satellite program--was installed
at South Point on the island of t Iawaii because there it would have a
favorable look-angle at the probes at the time of their fourth-stage
retrorocket firings.
S-l L planned for the picture taking to occur as soon as the
probes entered orbit, before anything might go wrong with the
spacecraft, and this milestone was expected to occur over about the
0° longitude, which crossed parts of Europe and Africa. Lehan and
his colleagues knew that the quality c]f the picture taking would
improve as the diameter of the receiving ground-based antennaincreased, but the time constraint, as well as diplomatic and funding
considerations, did not permit the installation overseas of a new
large antenna, possibly one 200 ft or more in diameter. l-he
University of
Jodrell Bank,
an Air Force
Bank facility,
Manchester’s 250-f t-diameter radio telescope at
however, already existed. A secret meeting between
officer and Bernard Lovell, the director of the Jodrell
enabled STL to install temporarily an appropriate feed
and other specialized equipment on the antenna in support of the
picture-taking activity.
S1
-
The engineers appear to have given little thought initially as
to what might constitute a permanent system of stations for
supporting an ongoing program of unmanned solar-system spacecraft
exploration, and whether any of the antennas installed or modified in
1956 could become part of such a permanent system. JP1. engineers,
by contrast, began planning for a permanent system even before the
Pioneer lunar-probes authorization was issued.
JP1. looks to the future
Probably the strongest advocate for s ch a permanent system
/ Y,< /,, J)
was Lberhardt Flechtin, chief of JPL’s CEO Research S@ion.
More aware than his colleagues in the propulsion field of the likely
advances in electronics and the potential distances that could be
reached in space communications (l-able xx), he strongly urged, in
the spring of 1958, the development of a launch vehicle (Juno IV)
capable of delivering a 550-pound payload to the Moon and a 300-
pound payload to the planet Mars. Such a vehicle, he argued, was
needed “to accomplish significant missions competitive with the
USSR; lesser vehicles will only keep us to the rear in
accomplishment of missions. ” Juncl IV’S capability of soft landing on
the Moon, Rechtin pointed out, could eventually permit the
establishment of “quite stable” radio and optical telescopes on the
lunar surface.
As for Mars, Rechtin argued that the often discussed similarity
of this planet to the Earth would rnakc photographic exploration of it
“one of the major goals of prestige between the United States and
the USSR. ” Looking further into the future, he noted that
meteorological and surface-condition instrumentation could
determine “the practicality of putting people on Mars.” Rechtin
predicted that “if conditions on Mars are even slightly more suitable
than anticipated, the past success of the human race in new
exploration will unquestionably start the drive to Mars. Based on
human history, it will then be first come-first served on Mars. ” l-eft
unsaid, but most likely implied, was the desire that the United
States get there before the USSR.
Rechtin was not alone at JP1 in perceiving Mars and other
planets of the solar system as the ultimate goals of space
exploration. Albert Hibbs, who became the first chief of JF)l’s new
Space Science Division, recalled in an interview that “[W]e wanted a
good challenge, and that was & technical challenge, getting a
useful payload to a planet. It was really tops in engineering
challenge--propulsion, guidance, communications, you name it. ”
It was for this envisioned amt]itious program of lunar anc~
planetary missions that JP1 , and particularly F{echtin and his fellowcommunications engineers, desired in early 1958 to build a
permanent network of stations that could transmit commands
spacecraft, determine their positions relative to the Earth or
to
other
objects, and receive scientific and cngirrcering telemetry data from
them. Rechtin’s conception of a permanent network was based on a
consideration of the apparent motions of space probes and a
requirement, sure to be iniposed by any funding agency, to keep costs
to a minimum.
He knew that after a space probe launched from Cap& Canaveral
completed its injection phase, during which it would move rapidly to
the east, it would (due to a decreasing angular velocity as it gained
altitude) have an apparent motion from east to west that closely
approximated that of a fixed radio source. During this post-
injection phase the greatest components
motion will be due to the rotation of the
Obviously results in the probe apparently
the eastern to the western horizon of a
of the probe’s apparent
Earth, and such rotation
moving across the sky from
particular antenna station
once each day. Simple geometry dictates that the minimum number
of principal antenna stations that permits continuous, overlapping
monitoring (necessary as missions became more complex and longer
in duration) after the injection phase is three . Because
the world is divided into 360° of longitude, the three stations should
ideally be located 120° apart in longitude.
d Confid&rt that solar-system exploration would “continue in the
coming years, ” Rechtin and his colleagues--particularly Walter K.
Victor, head of the Electronics Research Section, and Robertson
Stevens, head of the Guidance 1 echniques Research Section--sought
a communication system design that would “be commensurate with
the projected state of the art, specifically with respect to
parametric and maser amplifiers, increased power and efficiency in
space vehicle transmitters, and future attitude-stabilized
spacecraft .“ Because of the later availability of the Army lunar-
probe launch vehicles (Jupiter IF{BM and a cluster of upper stages
employing Baby Sergeant rocket motors), they had just enough extra
time to design and install a communication system that could not
only support the Pioneer lunar probes, but also evolve into a
permanent system for supporting future solar-system exploration
spacecraft.
Choosing an antenna design
With regard to antenna design, Rechtin, Victor, and Stevens
ciesired an instrument with an accuracy of 2 minutes of arc or
better, Operation on a 24-hour basis dictated that this accuracy
would have’ to be maintained regardless of solar exposure and rapid
ambient temperature changes. Furthermore, “since missile [la
vehicle] firings cannot bc held up because the wind is blowing
somewhere around the earth nor can the bird [spacecraft] be
Inch
whistled back from a space mission when the wind comes up, the
antenna would have to be usable in winds of 60 mph and be capable
of withstanding (in a stowed position) winds of 120 mph.
Rechtin assigned William Mcrrick (head of the Antenna
Structures and Optics Group) to icientify an antenna design that could
satisfy these demanding requirements. Confident that JPL wouldreceive an lunar-mission assignment but aware that the “
procurement, fabrication, and erection of the antennas would be the
“longest lead time item” for carrying out such an assignment,
Rechtin made this assignment on 7 February 1958, nearly seven
weeks before the Pioneer authorization. Merrick concluded that the
desired antenna would have to combine the best features of a
precision radio-astronomy antenna and a precision guidance or
tracking radar. Merrick recalled later’ that the radio astronomers
and suppliers he consulted “questioned our sanity, competence in the
field ar)d/or our ability to accomplish the scheduled date [initially
November 1958] even on an ‘around the clock’ basis.”
Merrick and his colleagues rejected many existing antenna
designs because of foreign manufacture, high cost, inadequate
aperture, and/or acknowledged design flaws. Others, such as the
CSIRO’S 21 O-ft diameter antenna at F’arkes, Australia, and NRAO’S
140-f t-diameter antenna at Green Bank, West Virginia, were
eliminated from consideration because these prototypes would not
be completed until 1960 or later. 1 he Jodrell Elank type c)f antenna
was rejected because it was “too big and expensive” and its design
and assembly had required seven years.
Merrick and his colleagues ultimately chose a design that had
been initiated at the Naval Research laboratory in 1953, developed
further by t-toward W. 1 atel at the Carnegie Institution of
Washington, and refined by the Associated Universities, Inc. (AUI),
and that had just been completed by the E31aw Knox manufacturing
company in Pittsburgh. the 26-m-diameter (85-ft) antenna had a
cantilevered-equatorial mounting and very large hour-angle and
.
dcclination drive gears that gave high driving accuracy for relatively
low tooth accuracy and a low tooth loading during high winds. EIlaw
Knox, which priced the antenna at about $250,000, had already
received orders from the University of Michigan and AU I (for
erection at Ann Arbor and Green Bank, respectively), but neither had
been completed when JPL placed an order, with ARPA’s approval, for
Eventually, citing national priority, the
three antennas in April. .
Army was able to move one of these probe-supporting antennas to
the front of the manufacturing line,
Choosing a station site
That first antenna was slated for a site in the United States.
Rechtin later recalled the planned overseas stations “so rapidly
became bogged down in approval red tape” that their earliest
possible activation date gradually moved beyond the second Army
lunar-probe attempt. Three stations would be essential for possible
future long-duration flights to the planets, but the limited objective
of the Army lunar probes allowed JPL engineers to make do
temporarily with one antenna. Continuous around-the-clock
monitoring of the probes was of course impossible, but JPL
engineers could deliberately select a trajectory that would cause
them to arrive at the vicinity of the Moon when they were in the line
of sight of the single principle antenna. Also, they, unlike their
counterparts at S3 L., had no need for a separately located
transmitter station.the probes were slated to fly by the Moon (thus
requiring no retrorocket firing commands), and the desired pictureswould be taken automatically when a photocell mechanism indicated
that the probes were within a certain distance of the Moon.
With the expectation that probes would eventually be sent to
the planets and thus their received signals would be extremely
weak, JPL communication engineers desired a site for their single
initial principal antenna that would minimize outside radio
interference as much as possible. In addition to avoiding areas with
power lines, radio stations, radar transmitters, and/or considerable
numbers of aircraft passing overhead, they sought in particular a
natural bowl, so that the surrounding terrain could shield the
antenna from nearby towns and passing vehicles. The underlying soil
had to be suitable for accurate and stable support of the antenna,
and an access road, for transport of the sizable steel components of
the antenna, would have to be built for what was likely to be a
remote site. Finally, the more immediate funding and time
constraints of the Pioneer program mandated use of Govern merit-
owneci land.
Thanks to a search two years earlier for an off-lab site to test
rocket engines, JPL engineers were aware that an area near
Goldstone Dry [Lake at the Army’s Fort Irwin, located in the Mojave
Desert about 150 mi northeast of Pasadena, would meet these
criteria. After General John B. Medaris, the head of the Army
Ballistic Missile Agency, in mid-May 1958 overruled another general
who wanted to use the Goldstonc area for a proposed missile firing
range, the work needed to convert the site into the desired antenna
station swung into high gear. Carefully avoiding unexploded
ordinance lying in the area, workers constructed access roads, laid
the antenna foundation, and constructed support buildings during the
late spring and early summer. Soon after he steel components
arrived in mid-August, a crew from the Ratio Construction Company
began erecting the antenna. After the crew completed its work two
months later, the feed was installed and various optical and radio-
frequency tests were conducted to establish the system tracking
accuracy.
Choosing an operating frequency
Unlike their counterparts at S1-L, JPL engineers, led by Victor,
chose not to operate at the 108 Mtlz frequency being used for the
Vanguard and Explorer satellites. With future missions clearly in
mind, they noted in an early report that the presence of interference
at frequencies below 500 MHz would “seriously limit the growth
potential of any space communication technique” using a frequency
in this region. Victor at first favored a frequency in the region
between 1365 and 1535 MH7, where he anticipated significant
hardware developments for improving receiver sensitivities because
the region bracketed the astronomically important 21 -cm hydrogen
line. Colleagues soon convinced him that a stable, efficient
spacecraft transmitter operating in that region could not be built in
time for the Pioneer probe missions, however, and he instead opted
for a 960 MHz (L-band) operating frequency.
l-he hard work that ST1.. and JPL communications engineers
expended in setting LJp their respective systems of antenna stations
(which included several with smaller antennas at launch-point anddownrange locations) in relatively short time periods paid off in
very satisfactory operation during the actual missions. Various
rocket failures, however, prevented all but the second Army probe
(launched on 3 March 1959) from reaching escape velocity, and this
probe (Pioneer 4) passed too far away (37,000 mi) from the Moon to
activate the camera system. By then, the USSR’s .luna 1, launched on
2 January, had already passed within 6,000 mi of the lunar surface,
l.una 3, launched on 4 October 1959, took the first photographs of
the far side of the Moon.
Gaining approval for a permanent system
The expansion of JPL’s ground-support system for the Pioneer
lunar probes into a complete worldwide three-station network was
not inevitable. The first challenge to JPL’s plans came from STL,
which in late June 1958 iSSLJed a proposal that called for the
construction of three 250-f t-diameter antennas to be located in
t{awaii, Singapore or Ceylon, and near the eastern coast of Brazil.
The firm claimed that diSCLJSSiOnS with JPL and “a thorough analysis
of foreseeable space programs” (including a series of new probes
aimed at the planets Venus and Mars that STL was simultaneously
proposing) indicated that “the long-range interests of the United
States in high-altitude communications relay satellites and in
interplanetary space programs could best be served” by the
establishing of two networks of three stations each, placed at
intervals of about 60° around the equator of the earth.
- 16
Rechtin thought otherwise; he considered the proposal “a ploy
to block JPL’s [network plans] by forcing a study and reconsideration
of JP1.’s ARPA order [for three 26-m-ciiameter antennas]. ” He may
have been right. The estimated overall cost of STL’S proposed new
sy$tem was $34 million. How STL expected the government to
(
approve such a large sum in so short a time (the company claimed
that it could “realistically” complete construction of the first
antenna in Hawaii by 15 October 1959) is unclear. The proposal, in
any case, was not funded.
A greater threat came in early July 1958, when Deputy
Secretary of Defense Donald @larlOs questioned why S1’L and JPL
were developing two separate systems for supporting the Pioneer
lunar probes. In response, Rechtin traveled immediately to
Washington, and in a 8 July meeting at the Pentagon with Richard
Cesaro, chairman of an AFIPA advisory panel on tracking, he
acknowledged that JPL was using the extra time afforded by the
later launch dates of the Army lunar probes “to begin a longer range
space tracking program using the proper parameters. ” These
parameters included the 960 Mtlz operating frequency and the 26-m-
ciiameter antennas that would be “capable of tracking all vehicles
from a 330-mile altitude satellite to space probes to Mars. ”
Cesaro was impressed with Flechtin’s presentation, but asked
that JPL prepare a formal proposal for a “World Net” that would
consider as well the communications requirements of other intended
ARPA space programs. J P L ‘s Aetianeta .
rv T-racking
Network, issued on 25 July, considered (despite its title) such
requirements for six different space programs that the UnitedStates planned to undertake--manned space flight, meteorological
satellites, reconnaissance satellites, communications satellites
(both geosynchronous and low-Earth-orbiting), scientific satellites,
and space probes--as well as the detection of “noncooperative” (i.e.,
foreign) satellites. Comparing all the requirements ),
Rechtin and several colleagues suggested that two principal
overseas antennas could be most advantageously placed, for
supporting space probes and certain other space programs, at
Woomera, Australia, and somewhere in Spain.
Cesaro was once again impressed with JPL’s work, and
indicated to Rechtin his intention to recommend that “all the
tracking and computational facilities should be handled under
administration with JPL as the technical arm. ” Rechtin was
delighted with this recommendation, but nevertheless cautious.
believed that Cesaro “may be way over optimistic” in thinking
Army
He
that
“ARPA certainly has the power to do this and would put down any
rebel lion.” In particular, Rechtin warned a JP1 colleague that “we
should expect considerable uproar from the Naval Research
Laboratory who probably figures it knows more about tracking than
anybody else. ” The NRL’s Radio lracking Branch, under the leadership
of John 1. Mengel, had developed the Minitrack tracking system for
the Vanguard satellite program.
1 he basis for Rechtin’s caution was his knowledge that
Congress in the summer had approved President Eisenhower’s
request
Nation
into being
for establishing a civilian space agency, and as a result the
Aeronautics and Space Administration was slated to come
on 1 October 1958. NASA’s impending formation meant
that ARPA was gradually losing its status as the interim United
States space agency.
Furthermore, by early January it became clear that not only did
the Defense Department want a station network separate from any
set up by NASA (because their need for secrecy conflicted with the
new space agency’s professed openness), but also those involved in
setting up NASA’s manned-space-flight, satellite, and space-probe
programs desired separate station networks. As Rechtin feared,
JPL’s plans were also strongly opposed by Mengel, whose group had
already been transferred into NASA. Mengel claimed that the
installation of more Minitrack stations was more essential than
than overseas space-probe-supporting stations, because “the
satellite experiments and their associated tracking was more
important [than space probes] as far as NASA plans were concerned.”
Despite Mengel’s views, on 10 January 1959 NASA, which had
supported since early November JPL.’s development of a recommended
set of future lunar and planetary probes and had also acquired JP1.
from the Army, signed an agreement with the Department of Defense
that called for, among other things, installation of stations for
deep-space probes at Woomera and in South Africa. The preference
by NASA and JPL for South Africa as the host country for a dedicated
probe-supporting station derived from the fact that most space
probes would pass over southern Africa during the injection phase of
their flights, when it was vitally important to establish their actual
trajectories for later accurate pointing of the other probe-
supporting antennas.Overseas expansion
In establishing the overseas stations, Rechtin insisted that
they be operated by local nationals rather than “displaced
Americans. ” Desiring the best possible performance from each of
the stations, he reasoned (and was supported by later experience)
that this could be obtained from professionals “proud of their work,
held responsible, and cooperatively cc)mpetitive in spirit. ” NASA and
JP1. fortunately identified in Australia and South Africa
organizations--the Department of Supply’s Weapons Research
Establishment (WRE) and the Council for Scientific and Industrial
Research’s National Institute for Telecommunication Research
(NITR), respectively--that were eager to cooperate in the
establishment of the network for supporting space probes.
l-he WRE was managing the Woomera rocket range at which the
United Kingdom and Australian governments had been conducting
high-altitude missile firings over the past decade, and WF3E;
superintendent Bill Boswell anticipatecj that the addition of an 26-
m-diameter antenna could not only expand support of these firings
but also ensure Woomera “a leading place in satellite and space
research, ” NITR director Frank Hewitt anticipated that the antenna
would be a “most valuable scientific tclol” that could be used
between missions to conduct radio-astronomy research. He also
believed that the techniques involved with the antenna would be
fundamental to future intercontinental communications an activity
of great performance to a country quite distant from Europe and the
United States--and that therefore the NITR should become familiar
with them.
NASA sent site-survey teams to Australia and South Africa in
February and September-October 1959. With extensive assistance
from WRE, NITR, and other local officials, NASA and JPL eventually
identified and selected two appropriate sites: a semi circular bowl
open to the south at the edge of a dry lake bed known as Island
lagoon about 18 mi from the village of Woomera and about 30 mi
south of the range head, and a Y-shaped valley near the town of
Hartebeesthoek about 30 mi northwest of Johannesburg and 18 mi
west of Pretoria.
NASA funded the construction of the overseas stations and
sent field crews to erect the antennas and install the electronics,
but it was WRE and NITR that bore the responsibility for acquiring
the land, constructing access roads and support buildings, and hiring
staff to operate the station. With a new program of Ranger lunar-
impact probes scheduled to be launched beginning in mid-1961, both
agencies worked hard with NASA and JPL to ensure that the stations
would be ready in time. NITR’s success in doing so was made more
difficult by delays (occasioned by the Sharpeville township
disturbance and the Soviet Union’s downing of a United States U-2
spyplane in March and May 1960) in the signing of a diplomatic
agreement governing the station and other NASA facilities in South
Africa, By the time Ranner 1 was launched on 23 August 1961,
however, both stations were ready and the Deep Space
Instrumentation Facility (renamed the Deep Space Network in 1963)
at long last had become operational.Subsequent evolution
Anticipating that space probes would become more
sophisticated in future years and would eventually travel beyond the
orbits of Venus and Mars (in contrast to the fixed range of Earth-
orbiting satellites), Rechtin sought and received from NASA a
continuing commitment that a relatively fixed portion (generally
about 10 percent) of the Deep Space Network budget would be
devoted to research and development. This commitment allowed the
Network to evolve in a timely way in subsequent years, as new
requirements were anticipated and means to meet them were
conceived, tested, and installed.
In early 1961, for example, Flechtin recognized that NASA’s
deep-space program would soon be expanding very rapidly (further
Rangers, Mariner flybys of Venus and Mars, Lunar Orbiters, Surveyor
lunar soft-landings, and Apollo manned lunar landings). He could
foresee occasions when “so many flights [would be] operating at any
one time . . . that a single antenna at each DSIF station could not
conceivably carry the load. ” Rechtin envisioned a future situation
when project managers could be “confronted with impossible choices
between probes measuring dangerous solar flares, observing violent
effects c]n Mars, roving among the crevasses on tho Moon, and
carrying men into deep space. ”
New 26-m-diameter antennas were thus needed (to be
accompanied by a change in operating frequency to S-band (2388
MHz)), and the first of these antennas was installed at Goldstone in
early 1962. Although the Woomera and Hartebeesthoek stations
would continue to operate through the early 1970s, neither was the
site of the new overseas antennas. WRE; had difficulties fully
staffing the Woomera station, due to its isolated location (in the
outback about 200 mi north of Adelaide) and insufficient housing
staff members and their families. Although the WRE gradually
for
resolved the staffing and housing problems at Woomera, the long-
term solution was to find a new adequately shielded site nearer a
center of population. Officials from JPL. and the Australian
Departments of Supply and Interior eventually identified such a site
in the Tidbinbilla Valley, located 11 rni sC)lJt west of Canberra
(Australia’s capital) along the northeastern edge of the Australian
Alps. The station constructed at this site became operational in
March 1965.
NASA and JPL were quite satisfied with
the station at Hartebeesthoek, but Rechtin in
that relations between the governments of the
South Africa might eventually deteriorate, due
NITR’s operation of
particular was fearful
United States and
to condemnation in
the United States and abroad of the latter’s apartheid policies, to a
point where operations at this station would have to be sharply
limited and curtailed. He argued that any expansion of the station
would make it more costly for NASA to duplicate the station
elsewhere at a later date.
An initial survey of sites in Italy proved unsuccessful, A
#
survey team found natural bowls on the island of Sard~nia, but such
,.,
a location would be difficult to support logistically. Potential sites
near Rome would not have this difficulty, but they were less wellshielded and would create coverage gaps between a station here and
the one at Goldstone.
NASA and JPL ultimately chose a site in a valley near the
village of Robledo de Chevala, 31 mi west of Madrid, Spain, for the
location of a 26-m-diameter antenna. A second such antenna was
subsequently installed near the town of Cebreros, 8 mi southwest of
Robledo de Chevala, These stations became operational in July 1965
and January 1967. Despite some misgivings about dealing with the
Franco authoritarian government, NASA had been quite pleased with
assistance rendered by the Spanish government’s Instituto National
de T6cnica Aeronautic (INTA) in the operation of a Project Mercury
station in the Canary Islands, and this organization became NASA’s
cooperating agency for the new Deep Space Network stations in
Spain as well.
A major evolutionary step was the design and installation of
new 21 O-ft-diameter antennas at Goldstone, Tidbinbilla, and
Robledc) de Chevala. These were built in response to the expected
advent of more sophisticated spacecraft (as launch vehicles became
more powerful), which would create a requirement for an increasing
rate in the communication of data from the spacecraft back to Earth.
JPL considered a number of alternatives for meeting this
requirement increasing the power of the spacecraft transmitter,
electronic arraying of two or more 26-m-diameter antennas, and use
of existing large radio-telescope antennas--but economics and
availability considerations ultimately dictated the construction of
new large antennas up to 250 ft in diameter. After two years of
design studies and nearly four years of contract negotiation, ground
preparation, support-building construction, and antenna erection, the
first of the Deep Space Network’s large antennas became operational
in May 1966. Two other such antennas became operational at
Tidbinbilla and Robledo de Chevalla in April and September 1973.
The Deep Space Network expanded the newer of the 26-m-
diameter antennas at Goldstone in 1978 in order to add X-band (8.4
GHz) capability and increase the antenna gain (received signal
strength) for the two Voyager outer-planet missions. Antennas at
Tidbinbilla and Robledo de Chevala were similarly expanded in 1980,
This improvement was sufficient for the Jupiter and Saturn
encounters (1979-81) of the two spacecraft. The extension of the
VQ2U mission to include encounters with the more distant
planets Uranus in 1986 and Neptune in 1989, however, forced
Voyager and Network engineers to find new means to compensate for
a still more severe decrease in signal strength and thus avoid an
undesirable great limitation on the science data return.
One means was the installation of new 34-m diameter high-
efficiency antennas (so-called because their reflector surfaces’ are
precision-shaped for maximum signal-gathering capability) at
Goldstone in 1984, Tidbinbilla in 1985, and Robledo de Chevala in
1987. The 64-m diameter antenna and the two 34-m-diameter
antennas could now form a three-element array. This combination
(together with a reprogramming of two of the Voyager computers to
accommodate an image data compression technique) permitted a
higher data rate (19 kilobits/see).
Because a still higher data rate would be needed to meet the
imaging science requirements at Uranus and Neptune, Deep SpaceNetwork engineers sought and received permission from Australia’s
Commonwealth Scientific and Research Organization to add
temporarily (in 1986 and 1989) their 64-m-diameter radio
telescope at Parkes to t
link. The Network made
when the twenty-seven
Tidbinbilla array via a ground microwave
use of a second interagency array in 1989,
25-m-diameter radio-telescope antennas of
the National Radio Astronomy Observatory’s Very Large Array in New
Mexico were linked with the Goldstone’s antennas.
One further step taken for the Neptune encounter was the
extension of the 64-m diameter antennas at each station to a
diameter of 70 m and the the reshaping of their reflector surfaces
to improve their efficiency. These improvements, which increased
the effective signal capture of these antennas by 5:lp~r ce t where
completed at Tidbi#Ma.and Robledo de Chevala in+) and
Goldstone in 1988.
The Deep Space Network continues to evolve even today. The
original 26-m diameter antennas installed in the 1958-61 period
are no longer in service the one at Goldstone is now a national
monument, the one at Woomera has been scrapped, and th& one at
Hartebeesthoek is now used by South Africans for radio-astronomy
research. The second set of such antennas (those extended to 34 m
in the late 1970s) are nearing the end of their usefulness. The onset
of metal fatigue and the mechanical limitations of their late 1950s
design do not permit further upgrades to improve performance. l-he
Deep Space Network will therefore soon be replacing these antennas
with 34-m-diameter multifrequency bearn-waveguide antennas.
These new antennas will allow critical weather-sensitive
microwave components to be located in an equipment room in the
antenna pedestal rather than on the rotating and tipping main
reflector. The first of these new antennas was recently installed at
Goldstone and will shortly become operational after completion of
performance testing.
To probe further
The author is nearing completion of a book-length history of
the Deep Space Network that will be based on published sources, oral
history interviews, and unpublished dc]cuments in archives in the
United States, Australia, South Africa, and Spain. Photocopies of
the documentation supporting the book (and the article above) will
be deposited in the JPL Archives. His article “Designing the United
States’ Initial ‘Deep Space Networks . ...” jEEE Antennas and
+Qtion ‘aaazine’ vol. 35, no. 1, February 1993, provides
additional detail concerning the choices of antenna design, operating
frequency, and antenna location made by STL. and JPL for supporting
the Pioneer lunar-probe attempts of 1958-59.
William R. Corliss’s A History gf the Deep Space Netw@
