A Review of Photography of the Earth from Sounding Rockets and Satellites

This paper reviews the methods and recent results of hyperaltitude photography, or space photography (pictures taken from space), of the earth, and discusses the potential applications and problems of space photography. Stress is placed on pictures of the earth's surface rather than cloud cover. Numerous pictures have been taken from sounding rockets, chiefly Vikings and Aerobees, launched from White Sands Proving Ground, New Mexico, and Fort Churchill, Manitoba. These photographs include a large number of infrared pictures, taken on 4 x 5 inch film with a 25A filter, which are among the most useful for terrain analysis. In those infrared pictures taken from altitudes of 65 to 158 mi. the average scale ranges from 1:820,000 to 1:1,700,000 and the useful coverage per photograph from 2700 to 43,000 square miles. Several score color pictures have been taken on Mercury flights with 35mm and 70mm cameras. The areas photographed include northern and central Africa, Florida, the Bahamas, the Middle East, and southern Asia. Many are of excellent quality and useful for geological and meteorological study. The potential uses of space photography of the earth, based on its uniquely great synoptic areal coverage, include: (1) geologic mapping, (2) topographic mapping, (3) forest cover mapping, (4) icepack and iceberg monitoring, (5) hydrologic studies, (6) supplemental information for meteorological television satellites, (7) oceanographic studies, and (8) supplemental data for conventional aerial photography by the use of long focal length cameras. The potential extraterrestrial uses of space photography lie in the photographic reconnaissance of the moon and planets by fly-by probes and in the interpretation of future and presently available pictures of the planets. The chief problem areas of space photography include: (1) delineation of specific uses, (2) determination of the best operational methods, (3) development of specialized cameras and films, (4) development of interpretation techniques, and (5) clarification of legal problems.