SMITHSONIAN INSTITUTION
ASTROPHYSICAL OBSERVATORY

OFFICE OF THE DIRECTOR

ASTROPHYSICAL OBSERVATORY

60 GARDEN STREET

CAMBRIDGE 38, MASSACHUSETTS 1 May 1963

Dr. Joshua Lederberg

Department of Genetics

Stanford University School of Medicine
Palo Alto, California

Dear Josh:

As we discussed several months ago, I am enclosing two copies of the
manuscript by Cyril Ponnamperuma, Ruth Mariner and myself on the synthesis
of ribonucleoside phosphates under possible primitive earth conditions.

We would be very grateful if this paper could be considered for submission
to the Proceedings of the National Academy of Sciences, either by yourself
or by Arthur Kornberg. I am also enclosing two copies of a paper on the
synthesis of adenosine which we submitted several weeks ago for publication
in Nature. We would, of course, welcome any suggestions which you or Pro-
fessor Kornberg might have for improving the manuscript. Cyril has just
told me that the luciferin-luciferase assay for ATP in our system was posi-
tive. We would hope to insert this result as a separate paragraph in the
manuscript.

I have been spending a great deal of time getting my work routine or-
ganized here at Harvard and Smithsonian, and preparing the lectures for a
course which I am giving on planetary physics. The literature seems full
of half-truths and self-replicating misunderstandings. The codification
and coherent presentation of present knowledge on planetary physics turns
out to be a more difficult task than I had imagined, but the experience is,
a very rewarding one. .

I am enclosing, finally, two planetary reprints which may possibly be
of some interest,

There is a good chance that I will be spending two or three weeks at
Ames at the beginning of August. Is there any chance of seeing you then?

With best regards,

Sincerely,

LE

Carl Sagan

CS/reg
cc: C. Ponnamperuma
Enclosures (6)