Science: Radio from Mars

The romantic theory that Mars is inhabited by an intelligent race was easier to believe before the development of radio. Intelligent Martians would surely discover radio. They would hear at least some of the radio chatter on earth, and earthlings would hear some of theirs. The fact that the earth cannot listen to Martian radio programs is contributing evidence that ancient, intelligent Martians do not exist.

Radio signals of a sort, however, do come from Mars. Last week the Naval Research Laboratory announced that Cornell H. Mayer, Timothy P. McCullough and Russell M. Sloanaker detected faint 3-cm. waves as Mars drifted across the field of the laboratory’s 50-ft. radio telescope. There was no doubt that the waves came from Mars, but they were so feeble that more than 100 observations were made to eliminate “random noise” from earthly sources.

The Martian waves brought no intelligent message, but one bit of information could be extracted from them: Mars is a chilly place. Since all materials give off radio waves whose intensity is related to the temperature, the Navy’s researchers could estimate that the average temperature of the Martian disk is a little below the freezing point (32º F.), a figure that agrees nicely with other estimates of the Martian climate. The poles are certainly colder than 32º F., and the center of the disk, where the sun stands high in the Martian sky, is presumably much warmer. The average temperature of the earth’s disk, measured by radio from Mars, would come out about 59º F.