GENERATION OF LIGHT

Otago Daily Times, Issue 23649, 5 November 1938, Page 11

GENERATION OF LIGHT

AURORA SIXTY MILES HIGH (From Our Own Correspondent) SYDNEY, Oct. 26. A plan for illuminating large areas of country by means of upwardly projected radio waves was explained by its originator. Professor V. A. Bailey, professor of experimental physics in the University of Sydney. Professor Bailey said chat the scheme was to create a huge electric discharge in regions about 60 miles above the earth. The principal was similar to that employed in mercury and other vapour lamps and neon tubes, but no connecting wires or glass envelopes would be used. If sufficient energy was supplied, he said, the area illuminated would be 5000 square miles, and the intensity of the light would be similar to that of full moonlight on a clear night. The light would have the appearance of emanating from a glowing cloud about 10 times as large as the moon. In effect, it would be an artificially generated aurora. The light might be slightly coloured—perhaps pink. Professor Bailey said that for the area mentioned about 1,000,000 kilowatts would be required to produce an illumination on the ground equal to that required for roadway lighting. That was a large amount of energy, but its use might be justified for certain commercial or military purposes. A noticeable effect could, however, be produced in the sky even with 500kilowatt radio transmitters similar to those used by the Cincinnati (U.S.A.) and Moscow broadcasting stations. He hoped that one of these might be used for experiments. An arrary of aeriels about a mile square would have to be provided, which would be able to radiate the energy, at a suitable wavelength, in a narrow vertical beam. Apart from any commercial or mill* tary value the scheme might have, Pro. fessor Bailey it would certainly have important scientific value, as i* would enable controllable spectroscopic and other investigations to be made of the atmosphere at heights of 60 miles or so.

The scheme is the outcome of re search done by Professor Bailey at the University of Sydney into the motions of electrons in gases in the presence of a magnetic field. Professor Bailey'* earlier work on this subject has been published in the London Philosophical Magazine and in Nature, and his first reference to the generation of artificial aurorae was made in the specification of a patent application lodged ip November, 1936.