CALIFORNIA INSTITUTE OF TECHNOLOGY
PASADENA, CALIFORNIA

GEOLOGICAL SCIENCES

February 7, 1961

Professor Joshua Lederberg
Department of Genetics
Stanford University

Pale Alto, California

Dear Josh:

Many thanks for your comments of January 19th concerning
ice on the moon. I have sent a copy of the manuscript to
Abelson. We are now constructing amodel which is applicable
to Mercury as well as to the Moon and in addition to satellites
of other planets. When it is completed I will send you a copy.
In addition, there should of course be moisture at depth as
you suggest.

With all warm wishes,
Sincerely,
¢
Plemeser
Harrison Brown

HB/eb