Authentic Science Fiction Monthly No. 53 — page 74: what you’re looking at

Machine-transcribed from the original scan — historical spelling and the odd misread are preserved.

EXPLORATION ...... OPENING UP HERE THOMAS BOND, A WAR-TIME WORKER IN THE PENTAGON, TELLS ABOUT THE EARLY STAGES IN MAN’S ATTEMPT TO CONQUER A PLANET. once we have three old terrestrial measurements to be considered in our new location. The time at which each picture is taken is important because from it we know the relative position of the sun at a given longitude and latitude, and hence the length of shadows thrown by objects of a given height. Before our journey started the Astronomer Royal of our time will have been able to get his boys and girls—working on the artificial satellite observatory—to es- tablish an equator and an axis of rotation for our planet and solar inclination tables for our. reference. No small job of work, even with the aid of such calculating devices as will then be available. We will have quite a good mechanical mathematician aboard. It will have among other duties, the job of maintaining an uninterrupted record of our position with reference to the equator and poles of our planet for the duration of our reconnaissance cruise. The altitude from which photographs were taken will also be a factor in the calculations which will produce the maps and again a new type of measure- ment of distance of war-time develop- ment will be useful. Obviously an altimeter of terrestrial navigation type will be useless. It depends upon atmospheric pressure. Our planet may not have an atmosphere. And if it has, it will differ from ours in depth and composition in such a way that any accurate prediction of its nature will be unlikely before we start our journey. It will not be possible to con- struct an aneroid barometric altimeter. x NINE commiclbooks. conn