The announcement by President Eisenhower in August, 1955 that the United States were including in their programme for the International Geophysical Year the launching of artificial earth satellites, was received with great interest in this country and elsewhere. There was some disappointment felt when, some months later, the proposed inclination (40°) of the satellite orbit was announced, for it was realized that there would be few opportunities available for observation of such satellites from Britain. The satellite subcommittee set up by the British National Committee for the International Geophysical Year to deal with all matters concerned with satellites, did not feel justified in planning any considerable observational activities in relation to the proposed American satellites, at least as far as stations in Britain were involved. The possibility of using radar detection was examined and development began of radio-interferometers operating on the frequency 108 Mc/s chosen by the Americans for their satellite radio beacons. Meanwhile, at the I. G. Y. conference at Barcelona in September 1956 the Russian delegation made the official announcement that the U. S. S. R. also proposed to launch satellites containing scientific instruments during the I. G. Y. No other details were given, but a recommendation was approved at the conference that the beacon frequencies of all satellites should be chosen to be compatible with the American tracking system. By June of 1957 it became known that the proposed inclinations of the Russian satellite orbits would be much greater (about 65°) than that of the American so observation would certainly be possible from Britain. Information about the beacon frequencies was not immediately forthcoming but by the end of July it was confirmed that these could be 20 and 40 Mc/s, quite different from that chosen by the U. S. A. As this entailed considerable changes in the design of receiving equipment it was decided to wait until after the forthcoming I. G. Y. conference on Rockets and Satellites planned to be held in Washington from 30 September to 5 October 1957. In fact, as we all know, the first satellite was launched by the Russians on 4 October, the evening of the last full day of the conference—the announcement was actually made by Dr Berkner, the American organizer of the conference and I. G. Y. reporter for Rockets and Satellites, at a cocktail party given by the Russian delegates in the Soviet Embassy at Washington.
