AURORA AUSTRALIS

Otago Daily Times, Issue 20473, 30 July 1928, Page 10

AURORA AUSTRALIS

SCIENCE PUZZLED. What is the cause of the phenomena known as Aurora Australis, which were visible in Melbourne and other parts of the country last Sunday evening ? Similar effects, known as Aurora Borealis, or northern lights, are visible from time to time in the northern hemisphere, but science has not been able to solve the mystery of their cause. An auroral display generally comes in the evening, and lasts a few hours; but it may occur at any time and last for days. The association of the phenomena with polar regions has led to the theory that they are electro-magnetic phenomena, which are most strongly manifested at the ends of the great magnet, the earth. Artempts have been made to explain the lights as due to seasonal discharges of atmospheric electricity. The magnetic poles in the Arctic and Antarctic (i.e., the spots where tcr-estial magnetism seems to be at a maximum, and where the magnteic compass ceases to take a fixed position) seems always to be the centres of the auroral displays. The northern and southern magnetic poles are not directly opposif* one another as might be expected ; and the northern one has been moving in a north-westerly direction at a rate of about eight miles a year. The yacht Carnegie is being fitted out for a three years’ voyage in order to give scientists an opportunity of solving the mystery of magnetism. No iron or steel has been used in the construction of the yacht, because these metals attract magne tism. She is built of wood -md pen magnetic metals. By the study of the action of the magnetic compass under varying conditions and in different places during the three years’ voyage, together with the study of statistics relating to sun soots, earthquates, radio and telegraphic disturbances, and the Aurora Boreahs the sc mntists on board the r,,. negie hope to find a “ key fact ” which will enable them to solve the mystery of nae-netism, and perhaps the mysteries of light and gravitation.