Spots on the Moon

Air Force Observers James C. Greenacre and Edward M. Barr had a painstaking job: with the 24-in. telescope of the Lowell Observatory at Flagstaff, Ariz., they were to map a part of the moon--the well-defined crater Aristarchus, 27 miles in diameter. Both men were thoroughly familiar with the crater and its vicinity; Greenacre could hardly believe his eyes when he saw two bright red spots looming to the northwest and a third just inside the crater's rim. "I had the impression that I was looking into a large, polished gem ruby," he says.

The spots lasted less than 20 minutes that evening last October, giving Greenacre and Barr no time to rig apparatus and make photographs. Dr. John S. Hall, the observatory's director, reported what they had seen to astronomical authorities. He had not seen the spots himself, but he ordered a close watch kept on Aristarchus. The moon waned, throwing the crater into cold and darkness, but in late November, two days after the edge of sunlight reached Aristarchus again, Dr. Hall and four other observers saw a reddish area, twelve miles long and 1 1/2 miles wide, inside the rim right where one of the spots had been seen in October.

The glow lasted more than an hour. Before it began to fade, Dr. Hall telephoned nearby Perkins Observatory of Ohio State University, which has a 69-in. reflecting telescope. Graduate Student Peter A. Boyce was at the telescope's controls. Dr. Hall told him that something was happening on the moon in the Aristarchus region, but did not give the precise spot. Boyce aimed his telescope at the moon and spotted the reddish area promptly.

This independent observation is not so firm a support as a photograph would be, and it is not so informative as a spectrogram, which might tell what chemical elements are responsible for the red color. But astronomers are notoriously skeptical about strange eruptions on the moon, and these confirmed reports are unusually convincing. They also tend to bear out 1961 sightings by Russian Astronomer Nikolai Kozyrev. Dr. Hall believes that the fierce heat of returning sunlight may have released gases from the lunar interior. At a Dallas conference on newly discovered astronomical objects last week, Nobel Chemist Dr. Harold Urey suggested that the gas may have contained carbon in the form of two-atom molecules that cannot exist on earth. If further evidence proves that the spots really do exist and are indeed caused by eruptions of gas from the moon's interior, they will present one more difficulty for would-be lunar explorers.

This file is automatically generated by a robot program, so reader's discretion is required.