CO JAN 21 1963

18 January 1963

 

Dr. Joshua Lederberg
Department of Genetics
Stanford University
Palo Alto, California

Dear Dr. Lederberg:

The continued uncertainty in the development schedule of the
Centaur launch vehicle has again forced a redirection of the Mariner B
project. The spacecraft that was in design was expected to carry to
Venus and Mars in 1964 most or all of the scientific experiments which
had been approved by the Space Sciences Steering Committee of the NASA.
As you are aware, yours was one of the experiments which had been
tentatively selected.

With the severely restricted capability of the Atlas-Agena
-launch vehicle for planetary missions, it is not feasible to build a
dual-purpose spacecraft to go both to Venus and to Mars. Hence, as
has recently been announced in the press, it has been decided to fore-
go the 1964 Venus opportunity and to build a spacecraft in the 500 to
600-pound range which can carry out a restricted but scientifically
significant fly-by mission at the next availability of Mars.

We are inviting the Mariner-B experimenters to meet at JPL
on 31 January. The purpose of the meeting is to acquaint you with our
new design constraints for Mars 1964 and to solicit advice as to how to
achieve a maximum amount of good scientific information from the mission.
The meeting will convene at 9:00 A.M., and the morning program will in-
clude presentations by various JPL personnel on such subjects as Mars
trajectories, spacecraft design, payload capability, possible instru-
mentation, and testing schedules. The afternoon will be reserved for
unscheduled comments and discussion by the participants.

As a selected Mariner-B experimenter, you are welcome to attend
the meeting. It should be understood, however, that the 1964 spacecraft
does not have the capability of carrying a landing capsule. Consequently,
we are not specifically planning any discussion of capsule experiments
at this meeting.

//: if 2, vee Rp Hh, 0 LAL aa

Sylvan 0-6811 Marray 1-3661 Twx 7486%
JET PROPULSION LABORATORY California Institute of Technology « 4800 Oak Grove Drive, Pasadena, California

Dr. Joshua Lederberg -2- 18 January 1963

Please let us know as soon as possible whether you will plan
to attend.

Sincerely yours,

JET PROPULSION LABORATORY

Conmvag © W Aug dar

Project Scientist, Mariner '64

CWS: raj