Moon Pits

If the moon is indeed green cheese, where is the cat that will catch the mice that nibble the holes that are easily seen by persons with a strong pair of binoculars?

At Wellington, N. Z., Prof. A. C. Gifford of the Hector Observatory is something of a cat. The lunar mice, he suggested last week, are meteors. Others have believed that the multitude of craters on the moon's surface are the chilly orifices of extinct volcanoes, mementoes of the aeons just after the moon, a molten fragment, was flung off from the earth's mass, arrested in the heavens by the pull of terrestrial gravity and started in its perpetual monthly swing. Prof. Gifford's contention is that, since the moon has no appreciable enveloping atmosphere, a meteor whizzing into it at 40 mi. or so per second would not be retarded as it would be near earth, and burned to a "shooting star" and dust by atmospheric friction. At the moon, it flies on intact, strikes the moon with terrific impact. In a tenth of a second, the meteor is stopped, but it has penetrated two miles into the moon's stony crust. The friction of penetration heats the meteor to gaseous state, under such pressure that there is an instantaneous explosion "500 times as powerful as dynamite." After centuries of bombardment by swarms of meteors, the moon is everywhere pitted as by shell fire, not pocked as by eruptions. Measurements of pits made by meteors that reached the earth unconsumed are alleged to tally with lunar craters telescopically measured.