COSMIC RAYS

New Zealand Herald, Volume LXXIII, Issue 22393, 14 April 1936, Page 10

COSMIC RAYS

EXTENSIVE KESEAKCH INSTRUMENT ON AORANGI DAILY RECORD MADE ON FILM Inside a small special cabin on the after deck of the Aorangi, which arrived from Vancouver yesterday, is an instrument that is assisting scientists every day in their study of one of the greatest modern scientific problems. It is a cosmic ray meter, one of seven similar instruments established in different parts of the world by Professor Arthur H. Compton, professor of physics at the University of Chicago, who visited New Zealand in 1932 to conduct cosmic ray experiments. By Btudving cosmic rays, scientists j may eventually be enabled to change tho structure of atoms and create elements as they please. The seven instruments will measure the strength of the rays, and enable variations in the recordings to be correlated with such influences as magnotic effects, atmospheric electricity effects, and barometric pressure, that might produoe variations in tho manner in which the rays reach the earth. The meter on the Aorangi, which was installed by Professor Compton in January, will remain on board for a year, recording the intensity of tho cosmic rays each day on a long strip of bromide paper by means of an automatic photographic device. The chief officer, Mr. It. N. Turner, who is in charge of the instrument, will cut off a section of the film every 'third day, develop it, and send it to Professor Comjiton. No attention has to be given to the instrument, except to wind the clockwork which drives the automatic device. The meter consists of concentric metal spheres filled with 25001b. of lead shot, making a screen through which any radio-active rays cannot penetrate. The cosmic rays, however, penetrate the layer of lead. The cosmic rays cause a small current by the ionisation of the argon, and the magnitude of this is measured by means of an electrometer needle, which moves for 57£ minutes and is then brought back to the zero point, where it remains for two and a-half minutes. The movement is magnified 200 times by means of lenses, and then recorded on the strip of paper. Mr. Turner, who has made a study i of cosmic rays, said yesterday that Professor Compton, who had travelled from Honolulu to Vancouver on the Aorangi's last northward trip, was satisfied with the work of the instrument. It was too early to determine any results from the experiments. Another cosmic ray meter is installed in Hagley Park, Christchurch, which is the nearest practicable elevated land to the South Magnetic Pole. Professor P. W. Burbidge, professor of physics at Auckland University College, is associated with the experiments in New Zealand.