Academician lgor Tamm
Lebedev's Institute for Physics
Academy of Sciences
Moscow B 134,
USSR

Dear r'rir fessor Temm:

  My wife and I have just returned from a trip to London giving
an opportunity to answer your letter of last month, which was
received here on April 8th.  Being often a fellow sufferer I can
very we1 1 sympathize wtth your "agraphia" and ~111 just remark
that it is always a pleasure to hear from you.

  You and your family must be very fond of skiing to persist
after such difficulties.  I am afraid the same disease is prevalent
here as weil , especially since the mountains are only about 200 miles
away.  I can understand your distress about the incident of your
son's mountain climbing but on your account am relieved that it
came out well for him.

  Concerning your visit to the United States in September, my
colleagues and I would be delighted if you could take time to visit
Stanford University and perhaps to give a lecture here after the
Rochester Conference.  We will certainly be able to arrange for the
cost of your travel from Rochester to California if that 1s a
difficulty and will try to make  any other necessary arrangements.
My co1 league, Professor Schiff, with whom I belleve you are acquainted,
should be wrtY 1 ng you tc. confirm this invitation.  Let me just say
that my wife and I would look forward to seeing you again very much.

  Thank you for mentioning the name of Professor lerusalimsky.
In fact I have already written to him and hope for some exchange
of ideas.  In addition someeffort is being made through COSPAR to
arrange and internatlonat discussion of exobiology.  Until now,
not very much has happened; however, no matter of this sort can
be expected to be accomplished overnight and some patience is
appropriate.  On the other hand, the pace of technological
advance is not necessarily modulated by the obstacles to
international communication and we obviously do not have an
indefinite period of time to anticipate the direct exploration
of planetary targets.

  You asked about mlcroorganisms In water cooled reactors.
I have never seen the reactors in this country; however, I was
struck by the observation of numerous blue-green algae in the
reactor near Bombay, India.  The actual flux to which these
organisms are exposed should be measured.  In any case, the
question you raise is an apt one and I can just reply that it
requires investigation.  Another source of organisms that may
be unusually resistant to radiation may perhaps be found in the
agricultural experiments in whfch hlsh enerav SOLI~CIC~. nf n-=


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radiation are used in open fields.  In the vicinity of the source
there should be tremendous selection for bacteria with unusual
radioresistance.  However , I have not observed any published
information on this point.

Yours cordially,

Joshua Lederberg