UNIVERSITY of PENNSYLVANIA

PHILADELPHIA 4

The College

Botanica, LABORATORY
38th and Woodland Ave. April 6, 1961

 

Dr. Philli rrison-”
Department of sice
Cornell University
Ithaca, New York

Dear Dr. Morrison:

Following up our conversation at the Johnson Foundation, I would
like to outline my suggested alternative to the view and plan you
described (though I reserve the right to publish these ideas in more
detail).

1. It appears to be physically impossible for microorganisms to
survive (let alone grow!) at a surface subjected to the intense ultra-
violet radiation and the extreme dryness present on Mars. Hence the
Seotch tape notion seems foredoomed to failure.

Ithaca NY \

2. On the other hand, ultraviolet radiation and aridity could be
readily overcome by a macroorganism with sa suitable skin. ‘Therefor Py
the first Martian collecting box should take in a sample with a cookie
eutter rather than a sticky tongue. ,

g ‘Mes lIx0H

~~ ¢
P Morrison Physics, Cornell,

3- The best hope of demonstrating life in the sample lies in
assuming an absolute minimum about the Martian "plants." I suggest
as such a minimm that they are photosynthetic.

4. No matter what the detailed mechaniam of the photosynthetic
process may be, it should be demonstrable calorimetrically. That is ?
one could show that some of the light absorbed by the semple does not

‘a

appear as heat. Confirmation of the inference of a biological mechanism x
might be obtained with an action spectrum. y
¥
par
Sincerely, (Fr,
a*
et tel atte re
%
Lionel Jaffe 7
t
1S /ras LS
a o
Dear Dr. Lederkerg; ¥ ¥

I enclose this letter for your information, Ty arose out of "Fin
en informal talk of mine on spece plans and the Martian surface probe pwk=ams we
you have been so concerned with, I am not sure I-agree with Jaffe on 1.,but it = )\
may be a point worth discussing, Perhaps you would find it useful to write him, ~~