National Geographic : 1950 Oct
Seeing the Earth from 80 Miles Up BY CLYDE T. HOLLIDAY WARNING siren screamed and a red star shell soared high over the sun drenched desert. They signaled that in just two minutes another V-2 rocket would go roaring skyward from White Sands Prov ing Ground, New Mexico. Soldiers and scientists already had taken shelter in the massive concrete blockhouse from which the rockets are fired by remote control (page 515). Nerves were tense, for on this flight we were sending aloft a camera which it was hoped would photograph the earth from more than 80 miles up. "X minus one," announced a voice from a loud-speaker, meaning one minute to go. Then it started counting seconds: "Twenty, nineteen...twelve...seven...three, two, one, fire!" A brilliant whitish-orange flame burst from the rocket's tail (page 516). With a thun dering roar it started to rise, almost imper ceptibly at first, then gathering tremendous speed. Out of Sight in 30 Seconds In less than 30 seconds the V-2 was prac tically out of sight of the naked eye. Riding with it, besides our camera, were instruments to make rapid measurements of cosmic rays, the earth's magnetism, temperature, atmos pheric pressure, and other things during the brief two or three minutes that the rocket would spend in the little-known reaches of the upper air.* Trailing invisibly behind the rising rocket was a stream of telemeter signals radioed back automatically by the instruments, telling what they were finding up there aloft. These signals, recorded on the ground, would pro vide almost the only record of the results of the flight, since most of the instruments would be smashed when the rocket crashed in the desert a few minutes later. Designed by the Germans as a terror weapon, the V-2's traveled faster than sound and gave no warning of their approach. They caused heavy damage and many casualties in and near both London and Antwerp in 1944-45. Actually, however, the V-2's have been far more valuable in exploring the upper atmos phere in this country than they were as weapons of war for the Germans. Because so many skilled engineers were diverted from other projects to work on the V-2, its develop ment handicapped Germany's war potential more than the rockets' destruction interrupted the war effort of the Allies. In 1945 the United States Army captured 100 V-2's and brought them to White Sands. Since then they have helped gather much use ful knowledge of the almost unexplored ocean of air that extends more than 300 miles above the earth's surface. One of the most spectacular results of the flights has been high-altitude photographs of the earth taken from heights no camera ever had reached before. Photographs Show Earth's Curvature Within 15 minutes after our camera soared aloft on the V-2, a search plane had located the crumpled remains of the rocket in the desert and then returned to guide the re covery party to the spot. The camera was wrecked, but the film, protected by a heavy steel cassette, was unharmed despite crashing into the ground at a speed of 500 feet per second (pages 518-520, 527). A truly dramatic spectacle unfolded when the film was developed. The camera had taken photographs every one and a half seconds from the moment of take-off up to an altitude of 83 miles, then back down again to about 40 miles above the earth. On these photographs we saw what a pas senger on a V-2 would see if he could stay alive on the zooming ride up to that height and back again, and how our earth would look to visitors from another planet coming in on a space ship. Curvature of the earth was plainly visible on the horizon of these tremendous panoramas. Great mountain ranges, long river courses, and broad plains were mere details in the breath-taking sweep of the pictures. Single views covered more than 100,000 square miles. The highest of these photographs were made from altitudes six times as high as the 13.71 mile ceiling of the National Geographic So ciety-Army Air Corps stratosphere balloon flight in 1935.t * Army, Navy, and Air Force, and many universities and industrial firms participated in the V-2 research program. The author is a member of the staff of the Applied Physics Laboratory of the Johns Hopkins University, which took part under a Navy contract. t See, in the NATIONAL GEOGRAPHIC MAGAZINE: "Man's Farthest Aloft," January, 1936, and "Scien tific Results of the World-Record Stratosphere Flight," May, 1936, with photographic supplement showing the lateral curvature of the earth as photographed from 72,395 feet. Both articles are by Capt. Albert W. Stevens.