U.K. Satellite May Help Radio Communications

Press, Volume CI, Issue 29801, 18 April 1962, Page 9

U.K. Satellite May Help Radio Communications

(By

ALEXANDER MacLEOD]

LONDON. Commonwealth radio links may be greatly improved as a result of Britain’s firing of her first space satellite, UK 1. The satellite, soon to be thrust aloft from pad 17-A at Cape Canaveral by an American Thor-Delta rocket, is designed to study the composition of the ionosphere —the electrically-charged radio “mirror” that makes possible wireless communications around the world.

At certain times of the year lonospheric conditions make the reception of overseas short-wave broadcasts most uncertain. British scientists believe that, if more knowledge is gained about the actual composition and behaviour of the ionosphere, it should be possible to schedule programmes at times and on frequencies guaranteed to give good reception. In days of intense RussianAmerican space rivalry, it is sometimes forgotten that before the war Britain had her own fine tradition of astronomy and upper atmospheric studies. The discovery of the ionosphere was largely a British achievement and it is no coincidence that the UK-1 satellite will carry six experiments designed to advance still further man's knowledge of the radio mirror above the earth's surface. Details Still Mystery In spite of intensive research over the last three or four decades, the actual composition of the ionosphere is still largely a mystery. Skylark rocket firings from the Australian range at Woomera have yielded some information, but full study has had to await the use of satellites capable of measuring precisely the make-up of the ionosphere, and evaluating the characteristics of solar rays before they strike its upper layer. UK-I—or to give it its United States designation, S-51 —is crammed with the combined scientific efforts of specialists from four study centres —Imperial College, and the Universities of London. Birmingham and Leicester.

Looked at from the outside it is one of the most ungainly objects ever fired into space. Three large solar paddles stick out from it at different angles. The rest of the black, white and gold vehicle is a mass of aerials, discs and spheres, each with its own highly delicate measuring task to perform. The first major job U.K-1 will have to do in its 90minute circuits of the earth will be to study the behaviour of cosmic ray particles. In. the normal course, these particles hit the earth’s atmosphere only to be destroyed. This makes it impossible to measure them on the earths surface. Now, for the first time. Sir Harrie Massey and his team of space scientists will be able to differentiate between particles coming from outer space and others emitted by the sun. Study of Gases The other five experiments aboard U.K-1 will study the behaviour of the gases in the upper atmosphere and the ■ways in which they are changed when sunlight strikes them. This process is known as ionisation: electrons are split off from the atoms of the gases and create

the “mirror'' used in longrange wireless links. Separate instruments will count the number of electrons created by the ionising process, measure their temperature and detail the weight of what is left after the electrons have been removed. Three solar paddles, each set at a different angle to the satellite's gleaming surface, will measure ultraviolet light from the sun. Finally, to provide an even more complete picture of the types of radiation that cause ionisation, two other instruments will pick up and measure X-rays from the sun. A major reason for American enthusiasm to provide rockets for Britain’s first satellite venture has been the great success achieved by the scientists in building into UK-1 miniaturised equipment far in advance of anything so far designed by American technicians. It is understood that many of these ideas are already being taken over for use in a later series of American satellites. The rocket to be used in the firing is one of the most reliable in the United States stable. The Thor Delta has had only one failure in eight recent satellite shots. It is a 90ft, three-stage vehicle capable of speeds beyond 17.000 miles an hour. Oval Orbit Planned' If all goes well—and accuracy of firing is essential for' successful ionospheric studies —U.K-1 will go into an oval orbit taking it between 200 and 600 miles above the earth. The ionosphere is a very deep electricallycharged area with different characteristics at various levels. U.K-l’s flight could well double man’s present knowledge of the upper atmosphere. How car could—and should —Britain get with a space programme using American rockets? 1 To date three Anglo-Ameri-can firings are scheduled. There is to be an interval of some months before the U.K-2 attempt is made. This second experiment will include instruments for forecasting the weather, measuring low-frequency radio waves and assessing the amount of interplanetary dust in the upper atmosphere.

gramme. Work is proceeding on two fronts. The European Launcher Development Organisation plans to build and fire satellites up to a ton in weight and using Blue Streak as the main rocket. Another body, the European Space Research Organisation, will use a test range at Woomera for various rockets. Both these organisations are virtually certain to rely heavily on British rocketry. But neither is expected to succeed in launching a satellite inside the next five years. One of the virtues of the current use of American rockets is that British satellite scientists need not languish while E.L.D.O. and E.S.R.O. fight their way through organising committees. Several experts are hard at work designing spacecraft for use in joint European projects, Now that British satellites are at last to leave the laboratory and fly in space, these men will have practical as well as theoretical studies to help them as they plan new sputnik journeys.