NAVIGATION

SPACE TRACKING STATIONS

R.A. Leslie BEE


Robert A. Leslie has been Senior Assist. Secretary, Space Projects Branch, Department of Science since 1975. He served as an RAAF Radar Officer from 1942 to 1945 with the rank of Flight Lieutenant. In 1948 he became a scientific officer, Weapons Research Establishment, Salisbury, SA, advancing to senior scientific officer in 1954 and principal officer, Target Aircraft, in 1956.
From 1963 to 1967 he served as Station Director, Tidbinbilla and became Superintendent of the American Projects Division of the WRE in 1967. In 1969 he was Assistant Controller, American Projects Branch, Commonwealth Department of Supply, which position he held until 1975 when he was appointed to his present position.

THE first major milestone in the development of space tracking stations in the ACT was reached in 1965 with the opening of the Deep Space Tracking Station at Tidbinbilla to the south-west of Canberra. A second station at Orroral Valley was opened in 1966 and a third, at Honeysuckle Creek, in 1967.

The ACT was selected as the best site in south-eastern Australia for these facilities because of the availability of a quiet environment for receiving radio signals from Space, the closeness of sites to an urban area offering accommodation for personnel and back-up services plus the relative geological stability of the region.

Australia’s association with the US Space Programme began in 1957 when it operated US supplied tracking facilities at Woomera, SA, in support of America’s first satellites, Explorer and Vanguard.

The ACT stations, however, were to be intimately associated with all the great unmanned probes and the Apollo manned flights to the Moon — the high point of this era perhaps being the transmission to the world from Honeysuckle Creek of sound and pictures of astronaut Neil Armstrong stepping onto the surface of the Moon on 21 July 1969. His activities and those of ‘Buzz’ Aldrin were watched by the largest television audience in history via the Parkes/Honeysuckle Creek/NASA INTELSAT system.

Since then, the ACT stations have given support to a variety of unmanned deep space missions to Mercury, Mars, Jupiter, Saturn and to the reusable Columbia space shuttle.

The Australian participation in the US Space Programme has captured the imagination of the people and has the support of all governments, no matter what their political persuasions.

In opening the Deep Space station at Tidbinbilla on 19 March 1965, Prime Minister Menzies called the achievements in Space, one of the miracles of the 20th Century. Prime Minister Whitlam, in dedicating an addition to Tidbinbilla in 1973, said that even those who questioned the cost of Space exploration had been moved by its vision and audacity, and by the courage of the astronauts themselves. He said it was a matter of pride for Australians to be involved in this historic programme by having the NASA station in Australia.

Tidbinbilla. Courtesy of Canberra Times.
Fig. 12.1: Tidbinbilla. Courtesy of Canberra Times.

The Australian/American Agreement

In 1960, Australia entered into a ten-year agreement with the USA to support the expanding programme of the newly formed civil space agency, NASA. The US agreed to meet the costs of the programme envisaged, but Australia contributed $140,000 a year, which was the cost of local support at the time. The agreement was subsequently extended to 1980 and again to 1990. The Australian operating agency was originally the Department of Supply, but in 1976, the responsibility was transferred to the Department of Science (now Science and Technology).

After the Explorer and Vanguard projects, Australia provided support for NASA’s manned Mercury space flight. A tracking station was established at Muchea, near Perth in 1960, and Woomera radar at Red Lake, SA, was adapted in the same year. Both stations supported NASA’s first manned orbital flight by astronaut John Glenn in 1962 and the subsequent three Mercury flights.

At about the same time, NASA started preparing for a programme of Deep Space exploration which resulted in the establishment of a station at Island Lagoon, near Woomera, specially designed for very long range communication. This station supported NASA’s Mariner project which provided the first Deep Space probe that flew close to Venus in 1962, and it continued in operation until 1972 in support of the variety of NASA deep space probes that followed the Venus project.

President Kennedy’s announcement in 1961 of the goal, within the decade, of landing men on the Moon and returning them safely to Earth, gave a further boost to NASA’s need for support from Australia. A large sophisticated station was established at Carnarvon, WA, in 1963 to replace the Muchea station. It supported NASA’s second manned Space flight project, Gemini, and it went on to support the Apollo programme which achieved President Kennedy’s goal in 1969. A special satellite communication link was provided by OTC via one of the first INTELSAT commercial satellites that was specially positioned over the Pacific Ocean in 1967 to improve communications in our region for support of Apollo. The Carnarvon station was closed in 1974, upon completion of the Apollo programme and the subsequent Skylab mission which resulted in men working successfully in Space for periods up to three months. Skylab returned the compliment in 1979 when it provided a spectacular fireworks display for Western Australia upon re-entry near Esperance on the south coast, fortunately without inflicting any damage.

NASA had alerted us in 1962 to its need for a site in south-eastern Australia, for four or five new stations, which would be required to give support to its programme. The first requirement was for a second Deep Space Station. However, it was expected that this would be followed by a second manned Space Flight station and also special stations for the support of unmanned scientific and experimental satellites. This initiated the progressive building of the tracking station complex in the ACT.

The responsibility within the Department of Supply for administering the agreement with NASA for the establishment of tracking stations in Australia was carried by Lloyd Bott, who was then First Assistant Secretary Policy and Coordination. He was assisted by Ian Homewood, Assistant Secretary Projects, and the staff of Projects Branch, although, of course, many other sections of the Department were involved in such a large undertaking, notably Contracts, Stores and Transport Branches and the State Regional Offices.

Management of the Stations

The establishment and management of the station in Australia was assigned to the Weapons Research Establishment (WRE) at Salisbury, SA, which operated the Woomera Rocket Range, where it all started in 1957. Bill Boswell, as head of WRE, took a keen interest in the programme from the beginning, as did his deputy, Arthur Wills, Tom Lawrence and many others.

In 1962, when the size of the project, and the potential benefits in technology became apparent, it was decided to involve private industry in the management and staffing of the new stations. A special division of WRE, called the American Projects Division, was set up under the leadership of M.S. Kirkpatrick to streamline the task. This Division performed the task until 1969 when the peak load had passed and when it was becoming apparent that the ACT was the preferred site for long term development of the tracking stations. At the time, the American Projects Division of WRE was transferred to the Department’s central office in Canberra and became known as the American Projects Branch, under the leadership of the author. The Branch was transferred to the Department of Science in 1975 when that Department took on the role of cooperating agency under the tracking station agreement with the USA. The Branch is now known as the Space Projects Branch.

The activity resulted in close working arrangements with many NASA people from the Associate Administrator level to Network Engineer. People involved in the very early stages included Ed Buckley and Buzz Brockett of NASA headquarters, Ozzie Covington, Tec Roberts and Bill Wood from Goddard Space Flight Centre’s manned space flight network, Jack Mengle, Hal Hoff and Buck Heller from GSFC’s satellite tracking and data acquisition network and Eb Rechtin, Bill Bayley and Richard K. Mallis from the Jet Propulsion Laboratory (JPL) which is responsible for NASA’s Deep Space network. Christopher Kraft and Sig Sjoberg from the manned flight control centre at Houston, Texas, also paid a close interest in the stations. Al Ludington of GSFC was the formal contact for financial matters under the agreement.

Since 1962, NASA has maintained an office in Australia to assist in liaison. The position in Canberra has been filled by Ed Hartman, Ray Hooker, Willson Hunter and Bill Wood. Joseph Kerwin is the current representative. JPL has been represented by Richard Fahnstock, Mel Glenn, Walter Larkin, Phil Tardani and Douglas Mudgway. Walter E. Larkin is the current JPL representative.

Site Selection

The research for a site in south-east Australia, suitable for a number of tracking stations, was undertaken in September 1962 by NASA and WRE people operating as a team.

The general region for the site, in terms of latitude and longitude was dictated by the need for continuous communication with deep space probes from at least one of three sites around the globe. The location of the keystone station in the Deep Space Network had already been chosen, in Southern California USA, so the first requirement was for a site about 120 degrees west from there, and at about an equal but opposite latitude, i.e., south-east Australia. Similar arguments applied to optimising coverage for satellites in high earth orbit and to a lesser extent even for low earth orbiters.

The choice within this region was made on the best balance between a quiet environment for receiving very faint radio signals and the distance from a town or city that could provide sound support to an activity involving several hundred people. Very remote sites such as Woomera, while excellent from the point of view of freedom from interfering radio noise, are very costly considering the inevitably high turn-over of staff, the need for subsidised housing, etc, and the distance from industrial support.

Other factors were also weighed in the balance such as relative freedom from earthquakes or violent storms and firm soils or shallow bedrock, considering the large but fragile antenna structures required and the need for great stability and precision. Natural shielding of stations one from another, and from the nearest town or city, by a series of hills and valleys was also important. Thought was given to avoiding airlanes, at least those in heavy use, because of the possibility of blanking even for a fleeting second, at just the wrong time, and of course because of possible radio interference between the aircraft and the tracking stations, or vice versa. An over-riding consideration was the prospect of obtaining the necessary licence to operate highpower transmitters, to send signals to spacecraft, without interfering with established users of radio in the region.

The use of the radio frequency spectrum is governed by international convention, and the commodity, being limited, must be shared wisely. The frequency band of most interest to NASA in 1962, known as S-band (around 2 202 megahertz) was already assigned to radio relay links around some parts of Australia for the carriage of telephone traffic etc, however a higher frequency band for the links between Melbourne, Canberra and Sydney had been adopted leaving the way clear for the licensing of tracking stations in the ACT in S-band. Engineers of the PMG (now Telecom) have since expressed regret that they did not get in first and so force the tracking stations into more remote places, away from inter-city trunk telephone and television radio relay routes, but in my view the compromise was reasonable as radio frequency congestion is not really a problem here in comparison to most other, more densely populated countries, that manage to live with the congestion.

All but one of the stations that NASA wished to build in the ACT were accepted. The exception was a temporary station that operated in the frequency band already assigned to the Melbourne-Canberra-Sydney radio relay link. That station was established instead at Cooby Creek near Toowoomba in 1966. It was part of a network of stations to support NASA in pioneering efforts in the development of communication and weather satellites that play such an important part in our lives today. The station, being transportable, moved from Australia in 1970 to meet changing requirements, but not before it had made history by providing Australians with the first live TV programmes from overseas.

Having identified the south-west of the ACT as technically desirable for tracking station sites, there followed a period of further survey and negotiation for a particular site for a second deep space station in Australia, which was NASA’s first requirement, and to identify other prospective sites. Many Departments were involved but most particularly the Department of the Interior, or Administrative Services as it is known today. Finally, the present site of the Tidbinbilla Station

THE STATIONS

Tidbinbilla

An area of 364 acres was withdrawn from the lease of Mr N. Reid’s Oakey Creek Station (now Mr Harding’s Mulumba Station) for the site and the access road to the Tidbinbilla Road was made through the Congwarra Station of Mr W. Flint. An area of about 29 acres was fenced as the inner site of the tracking station and the remainder was returned to Mr Reid for agistment.

A contract for maintenance and operations services at the station was let to Space Track Pty Ltd in early 1963. This company was a consortium of de Haviland, Elliots and Amalgamated Electronic Industries (AET), formed for the purpose of the contract. Stan Joiner of de Haviland managed the contract for the consortium and John Gaibraith was the company’s senior representative for carrying out the task under the contract.

The design of the facilities for the station was undertaken by the ACT Regional Office of the Commonwealth Department of Works. Bob Irvine was the project engineer and George Dunlop was the architect. Basil Monckton and Lance Sharpe of WRE and Mel Glenn of JPL, worked with the Department of Works on the specification and acceptance phases of the construction. The contract for construction of the buildings, the power house and other facilities was let to A.V. Jennings on 1 July 1963. The attractive buildings, basically as we know them today, were completed within one year.

The driving force for the hurried establishment of the Tidbinbilla Station was the need for additional support for NASA’s rapidly expanding deep space programme. In particular NASA needed support from our longitude for the first probe to Mars; Mariner 4, in late 1964, while still supporting the Ranger lunar exploration project from the Island Lagoon Station at Woomera.

The author became the WRE Station Director, Tidbinbilla, in May 1963. The first task was to work with John Gaibraith of Space Track on plans to staff the station, for equipment installation and for the first operations. At the request of JPL, a team of engineers and technicians from the station spent the first half of 1964 at NASA’s Goldstone Deep Space Station in California,, becoming familiar with the techniques involved in the Deep Space Network and in assisting to assemble and test the electronic equipment destined for Tidbinbilla. Subsequently, the same group carried out the main work of installing and commissioning the equipment at Tidbinbilla in good time to take over support for Mariner 4 from Island Lagoon in late 1964. This cooperative exercise resulted in excellent working relationships between the US and Australian engineers and so became the model for most of the development that followed in the deep space programme in Australia and elsewhere.

The Tidbinbilla Station, known then as Deep Space Instrumentation Facility 42 (DSIF 42), consisted of a 25.9 m diameter parabaloid antenna on a polar mount, driven in hour-angle and declination, as for astronomical telescopes. The antenna structure was built by the US Blaw Knox Co on foundations built by A.V. Jennings.

The focus of the parabaloid is well above the surface, but this is not a very suitable place for housing large transmitters and efficient but complex receiving amplifiers needed for long-range communication. Consequently, the Tidbinbilla antenna uses the cassegrain system which involves a sub-reflector above the surface to place the focus at the bottom of the dish. The first signal amplifier was housed in a cone at the bottom of the dish and the 20 kilowatt transmitter was housed in a room just below, in order to minimise the losses between those devices and the antenna. The first signal amplifier used a new technique called Microwave Amplification by Stimulated Emission of Radiation, or MASER for short.

To receive very faint signals, it is necessary for the receiver to be tuned very precisely to the frequency of the incoming signal while, at the same time, being very selective against noise or interference outside the bandwidth occupied by the energy of the desired signal. The problem is compounded as the received frequency varies with the relative velocity of the spacecraft and the station (the “doppler” effect) which is large compared to the bandwidth needed for efficient reception. Probably the most unique feature of the station was its ability to lock on to, and track, the frequency of the incoming signal, while accepting noise and interference only within the band- width occupied by the energy of the signal. The first receiver at Tidbinbilla for instance, was able to receive the main signal (or carrier) from the spacecraft while receiving noise from a bandwidth of only 12 hertz, even though the carrier frequency varied by as much as 30 kilohertz, due to earth rotation alone, and much more when the course of a spacecraft was being altered by the gravitational pull of a planet.

The main aid to navigation of the spacecraft was the measurement of the “doppler” effect, which is a measure of the relative radial velocity of the spacecraft from the station. A signal transmitted from the station was received by the spacecraft, translated in frequency and retransmitted to the station. The received frequency was compared with the outgoing frequency to derive the radial velocity. The great accuracy required of this system for navigation in space stemmed from the stability of the station’s transmitting frequency and the ability of the receiving systems in the spacecraft and on the ground to “lock-on” to the incoming signal frequency and track it within a small part of one cycle. The frequency at that time was rated as stable within 1 part in one hundred thousand million, over the period required to measure the “doppler” effect. This resulted in an ability to measure a spacecraft’s radial velocity of say 100,000 mph with an accuracy of one in 10 to the eleventh.

Tidhinbilla. Courtesy of Canberra Times.
Fig. 12.2: Tidhinbilla. Courtesy of Canberra Times.
Viking photo of Mars.
Fig. 12.3: Viking photo of Mars.

Also, for navigation, but in its infancy, was the measurement of range to the spacecraft. This was achieved by transmitting a coded signal for return via the spacecraft. By comparing the received code with that transmitted the time-delay could be measured. Transmission over great distance was achieved by transmitting the signal slowly within a very narrow bandwidth, and accuracy was achieved by making the coded signal very long. Range measurements of high accuracy were achieved over great distances, but at intervals of time spaced well apart.

Information from the spacecraft, comprising data from instruments such as TV cameras and other sensors, and data on the spacecraft itself such as temperature, attitude, etc. was super-imposed on the transmission from the spacecraft and extracted at the station. Digital systems for transmission of data, which are common today, were relatively new in 1964, but digital systems were used by the first spacecraft supported by Tidbinbilla. A fine balance had to be preserved in the energy in the spacecraft signal devoted to information (the sidebands) as distinct from energy in the basic signal itself (the carrier) which was required for navigation, to ensure that both systems would continue to operate at the same distance from the earth.

Information collected by the station was transmitted to the network control centre in USA by means of teletype transmission followed by despatch of magnetic tape recordings by air freight. Voice circuits were provided for coordination and for some oral reports of spacecraft or station parameters. When Tidbinbilla started operations it was connected with network control by 5 teletype and 4 voice channels shared with other NASA stations in Australia, through a communications switching centre which was originally in Adelaide, but was progressively transferred to Deakin ACT from 1965 to 1968.

The original station was equipped with a digital computer. Although this was an efficient machine, which survived for more than a decade, its function could only be described as peripheral to the main activity in 1964. It provided means of converting brief messages about satellite or deep space probe positions into detailed tables of pointing angles and frequencies against time, for station operation, and it took angles and it took part in experiments in automatic reporting, automatic data reduction and automatic control that has led to much greater network efficiency today.

Tidbinbilla came on the air in December 1964 to support Mariner 4 which was launched on its way to Mars in November of that year. One week later, the Woomera Station was taken down to be converted for support of the Ranger lunar probe. The Tidbinbilla station had a staff of about sixty people at that time which struggled to provide about 11 hours a day tracking, 7 days a week, until Mariner 4 flew by Mars in July 1965. The pictures of Mars revealed the startling (but I think, disappointing) fact that the planet was covered with large craters and that it seemed at that time that Mars was more like the moon than the earth. To many, this served to emphasise the uniqueness of the earth within the solar system.

The signal strength at the encounter with Mars had little margin above station threshold so nothing could be lost. We even went to the extreme of asking the civil aviation authorities to exercise their powers to divert aircraft that could feasibly come between Mars and Tidbinbilla at the critical time of closest approach. Needless to say, there was joking about little green men from Mars popping up to ask what we thought we were doing, but it came as a shock when, right at the critical time, when Mariner 4 had gone behind Mars, the direct phone to Canberra Airport tower rang (for the first time ever) and we were asked if we were experiencing interference from a UFO. Later the object was identified as an errant weather balloon.

The first launch of a deep space probe supported by Tidbinbilla was Pioneer 6, which was put into an orbit around the Sun in January 1965, to report on particles and fields in space. This event put us in particularly close contact with scientists at NASA’s AMES Research Centre and in particular with the AMES Project Manager for Pioneer, Charlie Hall, who paid us a visit shortly after the launch. Pioneer 6 and several of its successors are still reporting on our space environment today. The spacecraft and the station were so well designed that the initial locking onto the spacecraft proved to be easy, but being beginners, we were nervous before the launch and asked many questions as to possibilities, that, although “old hat” to the experienced, helped in establishing standard contingency procedures for the network. The Pioneer project people were sympathetic to our concerns and cooperated in the dialogue.

Although Mariner 4 was the main reason for haste in establishing Tidbinbilla, the Surveyor project was a very close runner-up. Surveyor, a forerunner of manned space exploration of the Moon, was required to make preliminary surveys of several possible landing sites for men. In particular, it was to investigate the landing properties of the lunar surface before committing men to land on what otherwise may have been a sea of dust.

The goal of Surveyor was to make soft landings at various prospective sites for manned landings, to test the strength of the soil and to survey the surroundings by means of television cameras, and to make other observations. All this happened so quickly that we tried the patience of our colleagues in the Department of Works by asking for extensions to the Tidbinbilla buildings before they were half completed, while still pushing for the original completion dates.

The Surveyor project required specialists at the tracking stations to assist in controlling the spacecraft, based on the data received. At that time, in 1966, there was no way for instance, of transmitting live television from Australia to USA. Hal French was the leader of a team of nine engineers and technicians from the Hughes Aircraft Co. USA that joined us before the launch of Surveyor 1 in May 1966 and stayed until the final flight, Surveyor 7 in 1968.

Surveyor 1 was an outstanding success, achieving all of its objectives. Based on history, the project management, anticipating a few failures in the early stages of the new project, was not ready for the success achieved. Indeed we had been asked to put all our effort into preparing for the flight phase, and none at all into the lunar exploratory phase, as a soft landing was rated as unlikely to happen on the first attempt. Well it happened. There was Surveyor sitting happily on the Moon. It arrived during the mutual view period of the US station at Goldstone and the Australian station at Tidbinbilla. From the point of view of Earth, it was setting on USA and rising on Australia. What should be done? Operations from here on had not been rehearsed properly. In any case, the Surveyor Project Control was not manned for round the clock operations. Very much to the disappointment of the Tidbinbilla staff, particularly the specialists from Hughes (who had rehearsed anyway), the decision was made to await the dawn over the USA before starting to take pictures of the surface of the moon. In the event, the station staff had plenty of action to keep them on their toes in supporting seven Surveyor spacecraft over a period of 3 years.

One of the highlights of the Surveyor mission from the station’s viewpoint was the awakening of Surveyor I after the first lunar night. Today, similar spacecraft are kept warm at night by heaters driven by nuclear fuel but Surveyor had only solar cells supported by batteries that could not last the long and extremely cold lunar night of 14 earth nights duration. Paddy Johnston was in charge of the shift that finally awoke Surveyor 1, after the sun had warmed it up for a day or so and for that he received the “Prince Charming Award” from the network. Paddy later took up a position in the Deep Space Network at JPL and we still look forward to his brogue on the voice lines today.

The next major change at Tidbinbilla was associated with support for NASA’s Apollo project involving manned exploration of the Moon. The support was secondary to that provided by the new NASA station at Honeysuckle Creek and the history of our support for Apollo will be covered later under Honeysuckle. A new wing was added to the Tidbinbilla operations building (built by T.H. O’Connor in 1966) to house the Apollo equipment and a deputy station director, Don Gray, was appointed at that time to specialise in Apollo support. Regular deep space work continued in non-Apollo periods.

Missions supported by the station in this period included the Mariner 5 flyby of Venus in 1967, Mariner 6 and 7 flyby of Mars in 1969 and Mariner 9 which was placed in orbit around Mars in 1971. Much improved instrumentation carried in the later Mariners revealed extinct volcanoes and huge canyons which showed that the planet was, at one time, far less moonlike than previously thought.

The most significant development for Tidbinbilla since then was the completion of the 64 metre diameter antenna in 1973. The antenna was far enough advanced to lend its support to the last of the manned flights to the Moon in December 1972. The new antenna and its counter-parts in USA and Spain provided a major boost to the capabilities of the network to support deep space probes at greater range, or more complex missions involving the transmission of higher data rates at the same range.

JPL let the contract for the erection of the antenna to Collins Radio, Texas, in 1969 and the contract for the building extensions to cater for the new antenna was let by the Department of Works in 1971 to the Buckman Building Group. Information obtained from CSIRO’s 64 metre radio telescope at Parkes was used in the design of the NASA instrument and this is evident from the family resemblance between the two antennas. The 64 metre antenna was dedicated by Prime Minister Whitlam on 13 April 1973.

There were several changes in the management of the station at about that time. Tom Reid became the Station Director in 1970 and in 1971, AWA displaced Space Track as the maintenance and operations contractor. Frank Northey transferred from the Cooby Creek Station to become the Deputy Station Director responsible for the 64 metre antenna and its associated equipment.

The station went on to support a variety of deep space missions such as the Mariner 10 flyby of Mercury in 1974, the Viking orbiters and landers launched on their way to Mars in 1975, the Pioneers 10 and 11 flyby of Jupiter in 1973 and 1974 and the Pioneer 11 flyby of Saturn in 1978 and NASA’s Voyager Ito Saturn in 1980.

The station has been updated continuously with new equipment to improve the data gathering capability and to automate many of the operations. Digital computers are now in wide use at the station.

The latest change to the station configuration involved the extension of the original antenna from 26 metre to 34 metre diameter and to add the capability of receiving at X-band (8,450 megahertz), which is now used for communicating with the most distant probes. The original station was fully stretched in receiving Mariner 4 data at 8 bits per second from Mars in 1964. The station received Voyager 1 data at a rate of 44 kilobits per second from Saturn at a range 8 times greater than before, which represents a tremendous increase in ability to communicate, achieved in less than two decades.

Orroral Valley

The Orroral Valley site for a tracking station to support earth orbiting satellites, as part of NASA’s Spacecraft Tracking and Data Acquisition Network (STADAN), was selected in late 1963. The land was acquired from Mr Greenfield in April 1964 as notified in the Commonwealth Gazette No. 9 of 30 April 1964. An area of about 40 acres was fenced for the use of the station and the remainder of the land was returned to Mr Greenfield for agistment.

The contract for the construction of the station buildings, power house, antenna foundations, etc., was let by the Department of Works to T.H. O’Connor in August 1964.

Tom Reid became the Station Director of Orroral Valley in August 1964 and EMI Australia, in association with Hunting Engineering, accepted a maintenance and operation contract to support the station in September 1964. Ron Reynolds managed the contract for the consortium and Bill Brear was the contractor senior representative responsible for the task under the contract.

The construction work was completed in May 1965 and installation of equipment began. The 26 m antenna was erected by Collins Radio under contract to NASA’s Goddard Space Flight Centre (GSFC) and the electronic equipment was installed by the station staff and GSFC engineers. The station commenced operations in October 1965 on a basis of 24 hours a day, 7 days a week, in support of a variety of satellites already in orbit.

The station was formally opened on 24 February 1966 by the Minister for Supply, Senator Henty.

The main requirement of this station, as distinct from the long-range communication task of Tidbinbilla, was to be able to switch quickly from supporting one satellite to another, often with quite different characteristics.

The signal received from satellites in earth orbit are relatively strong but view periods are short; a few minutes being typical. Many of the supported satellites used different systems for transmitting data, or for receiving commands so the station had to cope with a variety of equipment for support of the individual satellites. Data from the satellites were recorded on magnetic tape and air-freighted to USA for study. Limited data were also transmitted directly to the flight control centre at GSFC by voice or by teletype.

Jupiter.
Fig. 12.4: Jupiter.
Saturn
Fig. 12.5: Saturn.

The station operated at first in one of the relatively low frequency bands assigned to space research; 136—138 megahertz for tracking and receiving data and 149—150 megahertz for transmitting commands.

Shortly after the dedication of the station, additional equipment was installed to provide for the support of up to four satellites simultaneously. The later antennas were less sensitive than the original 26 m diameter receiving antenna, which was then used mainly for the reception of relatively weak signals from satellites in high-earth orbit.

The earth orbiting satellites were tracked to define the orbits mainly by the Minitrack Station which was installed at Woomera before the launch of the first US satellites in 1958. Minitrack employs a static antenna array which enables the time of meridian crossing to be detected precisely. Minitrack was shifted from Woomera to Orroral in 1967 and is still operating today. As with the main building, T.H. O’Connor was the building contractor. The pointing angles of the tracking antennas at Orroral were also sent to network control to assist in determining the position of satellites in space. In 1975 the Baker Nunn camera, which can photograph satellites in space (when illuminated by the sun against a black sky), for very precise position finding, was shifted from Woomera to Orroral, where it exists today. Its function has been taken over mainly by a laser ranging satellite tracker which was installed at Orroral in 1975. The laser tracker measures the transit time of a pulse of light from the station to the satellite and back. At the time of writing, range can be measured to the remarkable accuracy of about 100 mm.

In 1971, the maintenance and operations contract for the station was put out to tender and on that occasion, AWA displaced EMI. Ron Stewart managed the contract for AWA, assisted by Les Page. Cohn Smith who had experience at Cooby Creek and Carnarvon tracking stations, was the contractor senior representative for giving effect to the contract at the site. Most of EMI’s staff at the Station transferred to AWA and little disruption to the operations occurred.

In August 1967, Tom Reid left the station to take control of the new NASA tracking station at Honeysuckle Creek and Dennis Willshire transferred to Orroral from the Deep Space Station at Woomera.

In the 1970s, satellites started to use a higher frequency band for their transmissions, similar to that used for deep space probes (known as S-band) and the 26 m antenna at Orroral was consequently modified to accept that frequency band in addition to the frequencies used by the earlier satellites.

A major change to the role of Orroral resulted from the completion of the Apollo programme of manned exploration of the Moon and the following Skylab manned space station experiment. At that time, NASA decided to close down the dedicated manned space flight network, including the Australian stations at Carnarvon and Honeysuckle. Support for future manned space flight programmes would be provided by the STADAN network of which Orroral was a part. Actually Honeysuckle survived as a member of the Deep Space Network, at the expense of the Island Lagoon Station near Woomera which was closed down instead.

A 9 m diameter antenna, designed for transmitting and receiving at S-band, was installed by Collins Radio in 1974. Building modifications to house additional electronic equipment were made by T.H. O’Connor. At the same time, the station was supplied with equipment to measure the range and the radial velocity of satellites with respect to the station. Also at that time, the station received digital computers (from Honeysuckle) designed for automatic editing of data from manned space-craft for transmission to the control centre in USA, at lower rates that could be carried on commercial communication circuits. These computers were also used to improve the service for unmanned satellites and for taking over some of the previous manual tasks such as station reporting and network communications.

Columbia Space Shuttle on launching pad.
Fig. 12.6: Columbia Space Shuttle on launching pad.

The station supported the cooperative US/Soviet Apohlo-Soyuz project in 1974 when American and Russian astronauts linked up vehicles in earth orbit and carried out joint experiments in space.

The next manned space project supported by Orroral was the reusable Space Shuttle which undertook its first orbital flight early in 1981. This vehicle is designed for use over and over again, so reducing the cost of putting satellites into orbit and opening the way for much greater use of space.

Dennis Willshire left the station in 1980 and Lewis Wainwright took over the station director responsibility. Lewis was the station director at Muchea in 1969 and later at Carnarvon. He transferred to Canberra in 1969 as the deputy head of Space Projects Branch.

Orroral
Fig. 12.7: Orroral.
Honeysuckle
Fig. 12.8: Honeysuckle.

Honeysuckle

The Honeysuckle Creek site for a tracking station, designed specially to support the lunar phase of NASA’s Apollo project for manned exploration of the Moon, was selected by a joint WRE/NASA team in 1965. The land was acquired from Mr Richards in September 1965 as notified in Gazette No. 80, 7 October 1965.

The contract for construction of the station buildings, antenna foundations, power house, etc., was let to T.H. O’Connor in 1965. The work was completed in December 1966.

As in the case of Orroral, a 26 metre antenna was erected by Collins Radio under contract to NASA’s Goddard Space Flight Centre (GSFC) and the equipment was installed by the joint effort of station and GSFC staff.

The station was dedicated by Prime Minister Holt on 17 March 1967. The first Apollo mission supported was the unmanned test flight Apollo 4 in November 1967 and the first manned space flight mission supported was Apollo 7 in October 1968.

Changes in administration occurred in the early phase of the station. In August 1967, Tom Reid transferred from Orroral Valley as the Station Director and shortly afterwards Tony Cobden of STC was appointed as the company senior representative responsible for operations under the contract. Norman Stevens managed the contract on behalf of STC.

The main requirement of this station, as distinct from the sensitivity of Tidbinbilla and the flexibility of Orroral, was reliability coupled with sufficient sensitivity to handle communications with astronauts at the Moon and receive their television and other transmissions.

The station was equipped with electronic equipment similar to that at Tidbinbilla and operating in much the same frequency band. The radio frequency part of the station was known as the “Unified S-band System” or USB for short. This name came from the fact that, for Apollo, a single two-way radio link between the spacecraft and the Earth could be used for everything including voice communication, sending commands, receiving data and measuring the range and velocity of the spacecraft. This system worked magnificently and met all the requirements, however the station was equipped with a back-up system operating in the lower frequency band (known as UHF) used for earlier manned space flight missions.

The station had the capability to handle simultaneous communications with astronauts on the Moon and with an astronaut in orbit around the Moon, together with command, data reception and range and velocity measurement for two spacecraft. The moon diameter as seen from earth is about 0.3 degrees which was also the width of the Honeysuckle antenna beam, so that it could handle both the orbiter and the lander.

The original data handling equipment installed at the station, and throughout the manned space flight network, was very advanced by standards of that time. Data transfer between the spacecraft with the mission control centre, via the stations, used digital methods with general purpose digital computers at the station, linked by high-speed communication circuits, to higher-power computers at mission control. Control of the Apollo moon missions was affected by rows of controllers; the first row dealt with the performance of specific spacecraft items such as propulsion, guidance, power, navigation, observing instruments, etc. Higher rows dealt with coordination of systems and ultimately, at the highest level, overall mission control was handled. The flexible digital system enabled each controller to see the data he needed to accomplish his specific task.

The display showed the parameter of interest against the predicted, or expected, value as a function of time. There were many outstanding scientific and technical achievements involved in the Apollo project but the demonstration of the power of electronic digital systems must have a high place on the list.

There were two other stations in the manned space flight network, like Honeysuckle, equipped to support the lunar phase of the Apollo mission, at Goldstone, California and at Madrid, Spain. Although there were less sensitive stations with similar view periods of the Moon at Carnarvon, Guam and Hawaii, still further back-up was required to enable separate stations to concentrate on the orbiters and the lander and to substitute for each other in case of station failures. In our case, this back-up came from the sensitive deep-space station at Tidbinbilla. As previously mentioned, special equipment was installed at Tidbinbilla so that the antenna could be switched over at short notice, from its normal deep space role, to support Apollo. This was done just before each manned flight mission to the Moon. Honeysuckle and Tidbinbihla were linked by a microwave relay system so that Tidbinbihla became a second receiving and trasmitting system for Honeysuckle which processed data from the spacecraft and commands to the spacecraft.

Shortly before the first moon landing attempt, when it became apparent that that landing would take place towards the end of the view period from Goldstone USA, and that most of the first moon walk would be in our view, NASA asked for assistance from CSIRO’s 64 metre radio telescope at Parkes to further enhance the receiving capability here for the most critical period. CSIRO agreed on the basis that NASA would make improvements to its equipment which would give long-lasting benefits to compensate for the loss of observing time that was heavily in demand. Dr E.G. Bowen was the head of CSIRO’s Radio Physics Division and John Bolton was in charge of the radio telescope at Parkes.

Receiving equipment, similar to that at Honeysuckle, was provided by NASA to adapt Parkes for Apollo, and the PMG Department took on the challenge of establishing special communication circuits to carry signals from Parkes to Honeysuckle for processing and subsequent transmission to mission control in USA. Bob Taylor of NASA’s Goddard Space Flight Centre cooperated with Parkes and Honeysuckle/Tidbinbilla in setting up the system. Bruce Window of Tidbinbihla was in charge of the Canberra tracking station team that went to Parkes to assist.

I think anyone reading this account will know that Apollo 11 achieved the first manned landing on the Moon at about 6.00 am. Australian EST on 21 July 1969 and that Astronaut Neil Armstrong stepped onto the surface of the Moon, followed by Astronaut “Buzz” Aldrin, about midday. Their activities were viewed live around the world by the largest television audience in history via the Parkes/ Honeysuckle/NASA/INTELSAT system.

Honeysuckle, with the help of Tidbinbilla and Parkes, went on to give reliable support to the following six Apollo missions to the Moon. Parkes was called in at very short notice to help communicate with Apollo 13 after an explosion in the spacecraft caused the moon landing to be called off and put the safe return of the astronauts in jeopardy. Equipment was reactivated and the communication circuits were re-established with great speed, and in time to provide the assistance sought.

The last mission supported by Honeysuckle, as part of NASA’s manned space flight network, was Skylab, a huge space station designed to test man’s ability to work in space for protracted periods and to make scientific observations from space. The staff of Honeysuckle had to be increased to cater for the long mission periods involved in Skylab even though it was known that this would be the last manned space flight project supported by Honeysuckle.

The station completed its support of Skylab in February 1974 and then started the process of converting to become a part of NASA’s deep space network using equipment from the Woomera station which had already been closed. Special data handling equipment for manned space flight was shifted to Orroral which took over support for future manned space flight.

In early 1970, Tom Reid transferred to Tidbinbilla to take charge of that expanding station and Don Gray became the station director of Honeysuckle to see through support for the Apollo program, the following Skylab and the conversion to the Deep Space role.

Armstrong on moon.
Fig. 12.9: Armstrong on moon.

Station Support

With the transfer of responsibility for the stations from WRE to the Central Office of the Department of Supply in 1969, it was necessary to establish services in Canberra to carry on where WRE left off. This led to the creation of the Network Support Facility (Aust) at Fyshwick in the ACT to provide engineering services in support of buildings and plant etc. Basil Monckton was the first director of the facility and Fairey Australasia provided engineering and technical services by contract. Ron Green of Fairey managed the contract and Len Vincent was the company senior representative for carrying out the task under the contract.

In 1977, Charlie Quiggin took over from Basil Monckton as the director.

A communication switching centre established in Adelaide by the PMG Department to optimise the use of voice and teletype services linking the NASA stations with the several network control centres in the USA, was progressively shifted to Canberra from 1964 to 1968 because of the concentration of the tracking stations in the ACT. It was housed in the Deakin Telephone Exchange. The PMG Department did not wish to operate the facility in Canberra so the Department of Supply took over. Kevin Westbrook, in charge from the outset, was supported by technical and operational staff of the Department.

In the early 60s, the task of the switching centre was to monitor and share out station use of teletype and voice circuits to USA, carried on cables laid on the seabed. With the introduction of commercial satellite services in 1968, much more data could be accommodated including the relay of spacecraft television pictures to the USA. The 1980 capacity leased from Telecom and OTC was two wideband circuits capable of transmitting and receiving data at a rate of 56 kilobits per second, plus several voice and teletype circuits. For the support of the Space Shuttle, three additional wide-band circuits were introduced in 1981.

With the consolidation of the NASA tracking stations in the ACT in the early 1970s, it became apparent that greater efficiency could be achieved by seeking support from a single contractor for all three of the NASA tracking stations in the ACT, and for the Network Support Facility. Fairey Australasia was the successful tenderer and Pat Rothery took over as the local company senior representative for the contract. He was succeeded by Jim Thompson in 1980.

NASA is planning to introduce a synchronous satellite relay system in 1982 to take over support of satellites in low earth orbit from its existing ground station network. This will eventually reduce the workload at Orroral Valley which will then only support satellites in high earth orbit. The staffing of Tidbinbilla and Honeysuckle, in support of deep space probes, has already been consolidated into one team.

At the time of writing, it seems likely that Orroral will be absorbed into that team in about 1984, which will then support high earth orbiters as well as Deep Space probes. Use of all the antennas to receive signals from the most distant probes simultaneously, will increase the range of communication.

AUSTRALIAN LANDSAT STATION

This account has so far dealt only with NASA space tracking stations in the ACT, however the headquarters of an Australian station has also been established here.

This station receives data, for use by Australia, from NASA’s Landsat series of satellites which cover the Earth every 18 days.

The Australian Landsat station has operated an antenna at Alice Springs to receive satellite images since October 1979 and a processing facility at Canberra since 1980.

Australia realised the potential value of Landsat images to the management of the continent’s vast resources soon after the first Landsat was launched in 1972, and became an accredited user of the data beamed to Earth from the satellites launched in 1972, 1975 and 1978.

Landsat
Fig. 12.10: Landsat.

However, without a receiving station, Australian users had to rely on tape recordings made by the satellites when passing over the continent. These recordings were relayed to the United States where they were processed to give images which were then despatched to Australia.

One of the US Landsat satellites,
Fig. 12.11: One of the US Landsat satellites, from which the Australian Landsat Station obtains data for map-making.

Without its own receiving station, Australia was at a disadvantage because it was only one of a number of countries seeking to book recording time. Moreover, each recorder could only store data from two complete orbits, thus limiting the opportunity to look at the continent. The Australian Landsat Station at Alice Springs is centrally placed to give complete coverage of the continent.

Its installation in 1979 followed the recommendation of the Australian Science and Technology Council.

The data acquisition facility at Alice Springs is equipped with a 9.14 metre steerable parabolic dish antenna and electronic equipment, for the reception and recording of Landsat multispectral scanner data and satellite measurement data onto magnetic tape. The antenna design allows all known and foreseeable transmission frequencies of resources satellites to be accommodated without expensive mechanical modifications.

The digital-processing section in Canberra provides bulk processing and precision processing of Landsat image~. Together, the two systems give a considerable degree of image processing and enhancement capability.

The latest satellite, Landsat 4 was launched on 17 July 1982 and with a lower orbit has a 16-day coverage cycle.

The orbit is designed to be sun-synchronous; that is, the satellite passes over each point at the same solar time each day. Due to seasonal changes, the sun’s elevation changes from winter to summer, and therefore shadows vary in length. The orbit is controlled so that the ground track remains close to nominal values and the spacecraft is stabilised by gyroscopes.

Each full scene is about 185 km square. It is formed of picture elements, called pixels, 79 m on the ground. A scanning mirror in the spacecraft sweeps over an array of detectors, each of which is designed to measure reflectance in a single band.

The bulk processing system at Belconnen, a suburb of Canberra, is based on an Interdata 8/32 minicomputer with 256 kilobites of core memory as the prime control element, a unique 256 megabite memory, a 256 megabite disc (shared with the precision system), a line printer and interactive keyboard display unit, CCT handlers and three image writing devices (a precision cathode-ray tube and two Optronics drum recorders — one colour and one monochrome). Input to the system is via high-density tape recorders identical to those in use at Alice Springs, the CCTs or from disc for previously written data.

The high density tapes sent daily by air from Alice Springs are processed to produce ‘quick-look’ images of one spectral band at a scale of about 1:4,000,000, from which cloud cover and data quality assessments are made. This provides the information for the Australian Landsat Station catalogues.

The high-density tapes are also played back at one quarter real time rates to disc to allow for expanded processing, providing the standard range of bulk-processed products. Scene-dependent statistics are calculated and used to derive destriping corrections and contrast stretch coefficients.

The bulk processing system provides CCTs or film imagery. Original transparencies are produced by using either the precision cathode-ray tube system for images (at a scale of 1:3,369,000) on 70 mm film stock or an Optronics drum recorder for images (at a scale of 1:1,000,000) on 240 mm film stock. Partial scenes are available on request at a scale of 1:2,000,000 (x2) or 1:1,000,000 (x4) on 70mm film, and at 1:500,000 (X2) or 1:250,000 (x4) on 250 mm film.

The precision-processing system is also based on an Interdata 8/32 minicomputer, with a line printer and interactive keyboard display unit, CCT handlers and access to the Optronics drum recorders. It is interfaced with a digital image-processing system (COMTAL) which enables the operator to view, enhance and combine the remotely sensed data with graphical overlays. Imagery is generated for recording in either digital form on CCTs, or as black and white or colour imagery on the drum recorders. Input to the precision processing system is either from CCTs or from disc (usually shared with the bulk system) for previously written data.

The main function of the precision processing system is to provide rectification to ground surveys or registration of a Landsat image to a reference image. The system can also perform all the bulk processed corrections, as well as specialised radiometric enhancements and image annotation.

The station sells photographic or computer compatible tape products without restriction.

Computer tapes, containing all four bands, are used by researchers or scientists to analyse data based on the spectral signature (the combination of reflectance values) of ground features.

Optographic products may be black and white single bands or combinations of three bands, each of which is printed in one of the three colours — blue, green, red — on colour film.

Colour composite imagery is the most easily interpreted of these choices. It has become conventional to use false colour similar to that produced by infra-red colour films. Thus, Band 4 is visible green, printed blue; Band 5 is visible red, printed green and Band 7 non-visible infra-red, printed red.

Don Gray, is the station director at Belconnen and Bill Kempees of Fairey Australasia is the chief engineer.

For Australia, with its large land mass and sparse population, satellite remote sensing offers an effective tool whereby the nation’s managers can obtain the type of information necessary to develop and conserve the natural resources and environment. The Australian Landsat Station gives Australia direct access to the satellites and enables these information needs to be satisfied.

Looking back over these past twenty years, there is a sense of deep satisfaction in this work. Compared to the primary effort in the United States, Australia’s contribution was small in magnitude, yet a vital component of some of the most momentous steps forward made by man in scientific and engineering achievement.

Reference

  1. Treat-v Series 1960 No. 2. Exchange of Notes between Australia and USA (constituting an agreement relating to space vehicle tracking and communications), 26 February 1960. Australian Government
  2. Treat-v Series 1970 No. 4. Exchange of Notes between Australia and USA to extend the agreement (ref.1.) for 10 years. Australian Government Printer.
  3. ‘A History of the Deep Space Network.’ WILLIAM R. CORLISS NASA CR-151915 (1976).
  4. ‘History of the Manned Space Flight Network, Satellite Tracking and Data Acquisition Network and NASA Communications Network.’ WILLIAM R. CORLISS NASA CR-140390 (1974).
  5. Mariner Mission to Venus. Staff of JPL. McGraw Hill Book Co.
  6. ‘The Interplanetorv Pioneers.’ WILLIAM R. CORLISS NASA SP 278.
  7. Surveyor Programme Results — 1969.
  8. ‘The New Mars. The discoveries of Mariner 9.’ WILLIAM K. HARTMAN AND ODELL RAPER. NASA SP-337 (1974).
  9. ‘Pioneer Odyssey. Encounter with a giant.’ ZIMMEL SWINDELL and BURG~SS, NASA SP-349 (1974).
  10. ‘The Viking Mission to Mars.’ WILLIAM R. CORLISS, NASA SP-334.
  11. ‘Mission to Jupiter and its Satellites.’ Science (The American Association for Advancement of Science) Vol. 204, 1 June 1979, Vol. 206, 23 November 1979.
  12. ‘Mercury Project Summary, including results of the Fourth Manned Orbital Flight May 15—16, 1963’, NASA SP-45.
  13. ‘Scientific Findings of Explorer VI — 1965,’ NASA SP-54.
  14. ‘Orbiting Solar Observatory Satellite — 1965,’ NASA SP-57.
  15. ‘Observations from the Nimbus-I Meteorological Satellite— 1965,’ NASA SP-89.
  16. ‘Apollo II: Preliminary Science Report — 1969,’ NASA SP-2 14.
  17. Satellite Images of Australia, KG. McCRACKEN and CE. ASTLEY-BODEN (Ed.) Harcourt Brace Jovanivich Group (Australia) Pty Ltd. Sydney 1982.
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