IONOSPHERIC RESEARCH AT BIRDLINGS FLAT

Press, Volume C, Issue 29684, 30 November 1961, Page 19

IONOSPHERIC RESEARCH AT BIRDLINGS FLAT

Phenomena in the upper atmosphere, which absorb rather than reflect radio signals and therefore complicate communications and meteorological observations, will be explored from a new site at Birdlings Flat byphysicists of the University of Canterbury. The project is being financed under contract by the Office of Naval Research of the United States Navy, which has contributed 40,000 dollars to the project over the last four years. The New Zealand Universities’ Research Committee will provide three caravans to house special equipment. Meteorologists often ran into trouble between 40 and 60 miles up in the ionosphere with their observations because electrons absorbed rather than reflected radio signals, said Dr. J. B. Gregory, a senior lecturer in physics, with whom the United States contract was made. This phenomena, noticed in earlier upper atmosphere work at the department's

Rolleston station, had not been properly examined because of difficulties about technique in research. The layer concerned had only recently started to be explored in detail by rockets. Because the trouble arose chiefly in winter, it was believed to be of meteorological origin, Dr. Gregory said. Dr. Gregory said it was intended to “map” with radio waves this layer, the characteristics of which were virtually unknown. It was above the area usually probed by baloons and small rockets, the weak radio reflections would be picked up by new aerial arrays. For this work a series of transmitting and receiving arrays was being erected at Birdlings Flat. Within the next fortnight, weather permitting, 16 radio masts 60ft high would be erected. Eight more masts would be put (ip in the next few months, and another 16 later next year. They would extend for half a mile along the beach. Dr. Gregory said that for such observations Birdlings Flat was equalled by few places in the world. There was a large unobstructed area of flat land and sea with very few buildings and little radio interference. Above all. it was comparatively handy to the university, so that the three caravans with equipment could be taken out as required instead of permanent buildings being erected. “We are very grateful to Mrs A. E. Birdling and the trustees of her husband’s estate for making this favourable site available,” said Dr. Gregory. Mr G. J. Fraser, a lecturer in physics who will assist Dr. Gregory, will undertake another research project with the same equipment. He will study wind velocities and turbulence in the upper atmosphere. His research technique will be to note the characteristics and movement of constantlytransmitted radio waves projeced vertically from the earth. A constant pattern will be formed by waves from a powerful pulse transmitter and array, and Mr Fraser will note the change in patterns which, in his own words. “pass above the earth's surface as cloud shadows move over the earth.”