National Geographic : 1953 Jan
101 National Geographic Photographer Richard II. Stewart Cruising Six Miles Aloft, This B-29 Measured Cosmic Rays from Canada to Chile Carrying members of a National Geographic Society-Bartol Research Foundation expedition in 1946, the flying laboratory of the Army Air Forces made a series of flights over a course 4,800 miles long to determine how the intensity of cosmic rays varies with latitude. Dr. W . F. G. Swann (left), Bartol director, here dis cusses plans with Col. A . E. Key, the pilot, and Gen. Curtis E. LeMay, commander of the Strategic Air Com mand and a trustee of the National Geographic Society. The author took part in several of these trips. sake of knowledge. This quest often leads to unexpected applications; X rays, radio, tele vision, and the release of atomic energy are examples. Another reason is that the energy of many of the primary cosmic rays coming in from outer space is far greater than any that man so far has been able to produce. The most power ful man-made atom smashers at present can not accelerate atomic particles to energies comparable with those of the higher-energy cosmic rays. The rays provide us with a preview of what to expect as progress continues and we become able to attain higher and higher energies by artificial means. Our balloon flights high into the atmosphere here in the north actually were only one small part of a world-wide attack on cosmic ray mysteries which is now being pressed by scien tists of many nations. The rays are being studied on mountaintops, on other balloon flights, with rockets that climb 80 miles high,* at sea level, and underground. Our expeditions also were part of a con tinuing study of cosmic rays sponsored by the National Geographic Society and the Bartol Research Foundation of the Franklin Institute * See "Seeing the Earth from 80 Miles Up," by Clyde T. Holliday, NATIONAL GEOGRAPHIC MAGAZINE, October, 1950.