Selenology: Water on the Moon?

SELENOLOGY Water on the Moon? For a decade, McDonnell Douglas Geologist Jack Green has stoutly argued that there is water on the moon. Not free-flowing, gurgling water, to be sure, but water that is chemically locked within rock. Now, with the aid of a half-century-old observation, he reported to an American Institute of Aeronautics and Astronautics meeting in Los Angeles last week, he has found additional evidence of lunar water.

Green has long believed that most of the major lunar features are volcanic in origin. Since volcanic formations on earth contain hydrous rocks, Green reasons, they may well exist on the moon. Merely heating such rocks to between 500°F. and 800°F., he says, will release as much as a gallon of water per cubic foot of rock.

While reviewing some long-forgotten notes, Green recently discovered that in 1910 Astronomer R. W. Wood had taken telescopic shots of the moon through a filter that absorbed light with a wave length of 3,100 angstroms.When the pictures were developed, they showed black spots on the lunar surface. Because the light reflected from sulphur is absorbed at 3,100 angstroms, Wood reasoned, the black spots on the moon must be sulphur.

Repeating Wood’s experiment with a filtered, 8-in. telescope, Green produced lunar pictures with black spots near the crater Aristarchus, from which astronomers have reported seeing a red glow—a possible sign of volcanic activity. To Geologist Green, it all makes sense. Sulphur is the most abundant of volcanic materials, he says, and wherever volcanic sulphur is found on earth, it is surrounded by hydrous rock.

Carrying his speculations one step further, Green suggests that if life or its fossil remnants are found anywhere on the moon, it will probably be in the vicinity of the telltale black spots on his moon photographs. In the water released from hydrous rock by volcanic heat, he speculates, a primitive form of life might have evolved.

Whether lunar life did evolve or not,, it would be worthwhile for astronauts to land near Aristarchus. There, by focusing solar rays on the hydrous rock, Green says, they can assure themselves of an ample supply of water.

* An angstrom is equal to one hundred-millionth of a centimeter and is used to measure the length of light waves. The word has nothing to do with Angst, but pays tribute to Pioneer Spectroscopist Anders Angstrom.