Home Page Science Frontiers

No. 33: May-Jun 1984

Issue Contents

Other pages











The moon's moonlets

The great lunar basins are not arranged randomly. They occur in bands -- not one band but several. How can this geometry be explained. One hypothetical scenario has the primitive moon surrounded by many moonlets 60 miles and larger in diameter, plying equatorial orbits that are unstable. As the moonlets' orbits decayed, some crashed into the moon's equatorial regions, blasting out a band of huge craters. The force of the impacts also caused the lunar crust to slide over the still-liquid core by as much as 90. When the next group of moonlets crashed, they gouged out a new belt of craters and shifted the crust still more. Magnetic measurements of lunar rocks tend to confirm that the lunar crust did indeed shift by large angles -- several times.

(Anonymous; "Did the Moon Have Moonlets?" Science Digest, 92:20, January 1984.)

Comment. Such events could also have happened on earth, which would account for tropical-zone fossils being found at the present-day poles.

From Science Frontiers #33, MAY-JUN 1984. 1984-2000 William R. Corliss