Remote sensing then and now

Canada has a notable history in the early development and application of aerial photography, photogrammetry and airborne geophysics to the mapping, resource development and environmental monitoring to its very large and remote territory. Topographers, foresters and geologists used aerial photography extensively, especially in the years immediately following WW II. Their combined experience in this art was heavily relied upon to develop the Canadian Remote Sensing Program. The term 'Remote Sensing, was first used by the U.S. Military to describe a type of aerial surveillance that went beyond the use of photography into the use of parts of the electromagnetic spectrum other than the visible such as the infrared and the microwave parts.

It was my privilege to have an appropriate scientific and technical background in order to have been in a central position as far as the launching of the Canadian Remote Sensing Program was concerned. Prior to 1963, remote sensing was militarily classified by the U.S. Department of Defence. U-2 aircraft reconnaissance flights, spy satellites and airborne infrared line-scanners were being used to great strategic advantage in Vietnam and in the Cold War in general. As a civilian with no access to classified technology, serving as a geophysicist in the Geological Survey of Canada (GSC) and active in all aspects of airborne geophysical methods, I was naturally interested in these things.

By chance, in 1962, I happened to serve on a United Nations Mission on 'photogeology and airborne geophysics' at the Geological Survey of Japan with William Fischer, chief photogeologist with the U.S. Geological Survey. He told me that the U.S. Department of Defence would shortly be de-classifying a lot of remote sensing technology and that he was hoping to get the USGS involved. So that I was, from the beginning, on the lookout for information. In 1963, the Environmental Research Institute of Ann Arbor held the first unclassified international symposium on remote sensing. Steve Waskurak from the GSC attended and brought back much valuable information.

Alan Gregory

During this period, there were two persons in Canada who had been working with remote sensing in Canada within the classified area. One was Trevor Harwood, a geophysicist with DRB and the other a geologist with Mt. Allison University, the late 'Harky' Cameron, Cameron was an ex RCAF navigator who had maintained his connections with the RAF and was able to get access to PPI radar images taken over Nova Scotia by the RAF Vulcan aircraft based at Goose Bay, Labrador. They were taken at altitudes of 30,000 feet and each one covered nearly half of Nova Scotia in one image. These images showed dramatic 'linears' which Cameron interpreted as major geological faults. The geological 'establishment' did not think much of his interpretation and nicknamed him "Faulty Cameron" which discouraged him from publishing. It is interesting to note, however, that his interpretation now stands as 'self evident', confirming Schopenhauer's words.

Trevor Harwood and Moira Dunbar, both of DRB, studied floating ice in the Canadian Arctic using aerial photography and remote sensing. This was, and still is, a subject of great concern to Canada, both from the point of view of unauthorized passage of foreign vessels through the N.W. Passage as well as providing information for safe surface navigation. Harwood organized the first infrared line-scanning survey of a test area in the Arctic which demonstrated the possibility of ice reconnaisance during the Arctic night. The Ice Branch had been conducting ice reconnaissance flights for several years during the summer, but had no information on winter coverage as they were using visual observation methods.

Both Harky Cameron and Trevor Harwood found interested listeners in the Geophysics Division of the GSC to any information on remote sensing which they felt could be revealed at that time. I vividly remember Trevor telling me in 1962 "the Americans have a dedicated C 130 and are 'shovelling' millions of dollars into it in the form of all kinds of remote sensing devices". I was very impressed with this because of my obsession with airborne methods of data gathering. It was also frustrating because of not having access to this information.

Lee Godby

This collaboration with the MAD group turned out to be very valuable to the future remote sensing program as their magnetic work for DRB was completed and five bright young engineers, including Lee Godby, later transferred over to the newly-formed Canada Centre for Remote Sensing (CCRS), providing much-needed electronic and computer expertise.

At the beginning of 1964 it became quite obvious to the few of us in the government who were interested in airborne remote sensing (before we envisioned doing it from space) that it could become a big and important activity for Canada for obtaining information for managing our resources and environment, especially because of our vast and relatively inaccessible land and continental shelf territories. How could we organize and promote this? As the mandate for airborne remote sensing would obviously cut across several governments departments (which later turned out also to be a major problem for the universities), the 'knee-jerk' response of we civil servants was to set up an interdepartmental committee. This had to be done at the working level, again because of the 'flakey' nature of the subject. After a year or so of the deliberations, we finally decided to recommend to the government the establishment of an aerogeophysical and remote sensing institute which would have a government-wide mandate. This was recommended in a bottom-up fashion to our various departmental senior officials. Several thought it to be a good idea and were prepared to push it up further, but unfortunately the idea became entwined in interdepartmental wrangles, such as which agencies had the mandate to operate aircraft and the proposal became stillborn.

The committee languished for a couple of years, becoming only a forum for the exchange of scientific and technical ideas which began to seem more and more like pipe dreams when a dramatic thing happened.

Civilian remote sensing in Canada would have developed incrementally had it not been for the proposal brought forward to the U.S. Government by Bill Fischer of the U.S. Geological Survey. By 1966, he had managed to convince the Department of the Interior and its then secretary, Bill Pecora, to sponsor an Earth Resources Orbiting Satellite (EROS). The satellite bus would be the same one that RCA had made for NASA's experimental meteorological NIMBUS program and the payload would consist of three bore-sighted, RCA, very high-resolution return-beam vidicons. Each vidicon would have its own optical filter, one for the near infrared band, one for the red and the other for yellow, corresponding to the three emulsions layers on camouflage film used during the war and found to be especially useful in airborne experiments to map vegetation. Bill Pecora managed to get approval for funding the satellite as an Interior initiative.

I invited Bill Fischer to come to Ottawa and meet privately with senior EMR officials and John Chapman ADM of the Satellite Communication Branch of Eric Kieren's newly-formed Department of Communications. After the success of the Alouette and ISIS programs Chapman had also become interested in satellite remote sensing. The meeting was held at the Royal Ottawa Golf Club. Jim Harrison ADM/EMR and John Chapman, Yves Fortier, director of the GSC and Sam Gamble, director of the Surveys and Mapping Branch were present.

Fischer, after briefing us on the EROS program showed some of the pictures of the Earth taken by the astronauts with hand-held cameras. At the time they seemed very dramatic indeed and impressed all of us. Chapman then offered the Prince Albert Radar Laboratory as a readout station for EROS. It contained an 84-foot diameter parabaloid tracking dish which was no longer needed as the ionosphere experiments, for which it had been erected, were complete. Fischer was pleased with the idea, as this station would be able to read out data for the whole of North America. At that time, no plans had been made for the readout of EROS.

Alas!, the U.S. Bureau of the Budget had EROS cancelled. NASA had complained that EROS would be an experimental space project, and as such was within the mandate of NASA. Mandates are very important in the government service. Nevertheless, NASA was honour-bound to come up with an alternative program which they finally did in 1969. It was to be called The Earth Resources Technology Satellite (ERTS). It was to retain the three RCA return-beam vidicons, but was also to have a new sensor, the multispectral scanner designed and made by Hughes, Santa Barbara. A vibrating mirror focussed the earth scene onto an array of solid state detectors arranged in five clusters, each cluster being sensitive to a different wave band, making five channels ranging from blue to the far infrared. The sensor was to have a ground resolution of 80 metres.

Our problem now was how to get the same deal with NASA on ERTS as we had with Interior on EROS, particularly as NASA originally had no plans to share their program internationally. John Chapman, who had successful cooperation with NASA on the Alouette and ISIS programs and I visited their Assistant Administrator to propose that Canada read out ERTS at Prince Albert. We were politely told "it would be foolish to invest in a readout and ground data handling facility as it would be too large a risk for Canada. It was costing NASA $40 million and besides, they could cover most of the Canadian landmass from their three readout stations in Alaska, Goldstone, Arizona and Wallops Island, New Jersey. Furthermore ERTS would carry an on-board tape recorder which could record any data beyond the range of the three readout stations". It was clear they did not want to have a foreign country reading out this satellite. Chapman appealed to the President Nixon's Scientific Advisor but to no avail.

Canada had a strong tradition, as did most states, of keeping the control of aerial photography and mapping within the country. We did not like the idea of having to purchase imagery of Canadian territory from a foreign country nor of having a foreign country acquire imagery of Canadian territory without advance permission. Such a concept was in violation of the Chicago International Convention which required any state wishing to acquire air photography of another country to first get permission. NASA took the position that in this case, the U.N. Treaty on the 'Peaceful Uses of Outer Space' applied - in which any state was free to conduct any activity in space provided it did no harm to other states (particularly in the case of falling debris).

The Deputy Minister of Communications, Alan Gottlieb and his legal advisor, Charles Dalfen, at first wished to make diplomatic objection on the grounds that the U.S. would be able to obtain exclusive information on the location of potential mineral and petroleum deposits in Canada by means of this satellite and might give advance information to U.S. exploration companies. By orbiting a resource satellite and taking imagery of Canadian territory, the U.S. would be invading our sovereign rights. In EMR, we took the view that it would be preferable for Canada, and indeed the international community, to gain knowledge of the technology which would allow us to better control the use of the data. To that end, Harrison, Gregory and I presented a paper at the International Astronautics Federation held in Brussels in 1971, in which we recommended that an international legal regime for the operation of remote sensing satellites, including the transfer of technology, be established. We suggested the establishment of an international network of readout and ground data handling centres and even supplied a map showing the possible locations of such a network. This aroused a lot of hostility from one of NASA's assistant administrators. Its publication was delayed for four years because the editor misplaced the manuscript and failed to notify me of this.

The next thing was to prepare for the reception of ERTS at Prince Albert. But before this, we had to reach an agreement in Canada on the organization and funding for an agency to implement the remote sensing program.

Whereas it is a relatively easy thing for the ruling party in the government to create a new government agency, it is nearly impossible to promote such a thing from the position of a division chief in a branch of one department because of innate interdepartmental rivalries and questions of departmental mandates (witness the lack of success of the previous interdepartmental committee on remote sensing). The solution was found in the suggestion by a consultant Mr. E.J. Robb from TRW, the U.S. Aerospace giant. He suggested going to Cabinet to ask for the establishment of an Interdepartmental Planning Office for Remote Sensing. This we did, and at the same time asked for an initial budget of $550,000 to do advance planning for the readout of ERTS and for the establishment of a Remote Sensing Centre - this was approved - to have a life of two years, at the end of which, an organizational and operating plan was to be submitted to Cabinet.

In early 1969, a document was sent to Cabinet by Energy Mines and Resources recommending the establishment of an Interagency Committee on Resource Satellites and Remote Airborne Sensing, supported by a Program Planning Office to set up technical working groups, prepare program forecasts for resource satellite and remote sensing programs and to plan and recommend an organization to carry out these programs. The governance, management and committee structure of the Planning Office was based on the model of the NRC Associate Committee on Geodesy and Geophysics, on which I had served in the fifties and sixties. This committee, among other things, had spawned Canada's very successful participation in the 1957 International Geophysical Year which, in many ways, set the stage for Canada's venture into space. It was this organization that led to the program becoming a truly national one, with most of the appropriate technical and scientific organizations and individuals in Canada being consulted and involved.

Analogous to the NRC Associate Committee on Geodesy and Geophysics, there were 14 sub-committees called 'working groups', each one of which had between 10 and 15 representative members from both federal and provincial governments, from industry and universities. Generally, working group leaders were selected from the various federal government departments where the required disciplinary expertise existed. In all, there were more than 140 scientists and engineers involved in these working groups, each of which, in the first year, met four or five times. This may have seemed like committee 'overkill', but we desperately needed lots of help to meet the ERTS launch date of July 1972. They were indeed 'working groups' and they had two jobs: firstly to educate themselves in this new technology, and secondly to do their part in preparing for the onslaught of data from ERTS--to reproduce, distribute and interpret the useable images of the 1500 or so, scenes of Canada which the satellite was to record every day, seven days a week!

In retrospect, these working groups performed beautifully. Each did its job with the result that Canada was fully ready for the launch of ERTS - probably even more so than the U.S. itself as we were a smaller, more tightly-knit organization.