Authentic Science Fiction Monthly, No. 66 — page 110: what you’re looking at

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

AUTHENTIC SCIENCE FICTION to a comparatively insignifi- cant crater-cone, difficult to see, even in large telescopes. Since then, other changes on the Moon have been ob- served to take place by. Dr. H. P. Wilkins, P. A. Moore, K. W. Abineri and others, in careful studies of selected areas. We will return to these later. Before doing so, let us sketch briefly the main features of our satellite. It is a globe some 2,160 miles in diameter, pursuing an elliptical orbit about the Earth at an average distance of 238,000 miles, though it can approach as close as 221,000 miles and recede as far as 253,000 miles. Its period of revolution is some twenty-seven and one third days. There being no free water on the Moon, the area of its surface is about 26 per cent. the area of dry land on Earth, so that its exploration will be a gigantic task, even if a dozen widely-dispersed lunar bases are formed. cornet One side is always turned towards us, though occasion- ally we can “see round the edges” a little, due to the 109 _librations, so that some three- fifths of its surface has been mapped. We even know a little about the two-fifths of its surface we never see! Dr. Wilkins has published a map of the other side, a rather tentative one, it is true, but based on the evi- dence of ray-centres. Some craters on the visible side of the Moon, such as Tycho and Copernicus, are the centres of vast radiating streaks. These rays extend in some cases a distance of many hundreds of miles and are usually from five to ten miles wide. They do not seem to be elevated or depressed with respect to the general surface but pass across valley and mountain. Some authorities explain them as a staining of the surface by vapours rising from cracks too narrow to be visible. Others suggest that the great craters, that are their focal areas, are connected with them in the sense that they represent a “‘spraying”’ of the surrounding landscape when the craters were active, or that the “spraying” was caused when giant meteors in the Moon’s turbulent past comiclbooks.corn