It was this same power that he used so successfully to implement the research and construction leading to Wildfire.

Stone was intrigued by Merrick's ideas, which paralleled certain concepts of his own. He explained these in a short paper entitled "Sterilization of Spacecraft," printed in Science and later reprinted in the British journal Nature. The argument stated that bacterial contamination was a two-edged sword, and that man must protect against both edges.

Previous to Stone's paper, most discussion of contamination dealt with the hazards to other planets of satellites and probes inadvertently carrying earth organisms. This problem was considered early in the American space effort; by 1959, NASA had set strict regulations for sterilization of earth origin probes.

The object of these regulations was to prevent contamination of other worlds. Clearly, if a probe were being sent to Mars or Venus to search for new life forms, it would defeat the purpose of the experiment for the probe to carry earth bacteria with it.

Stone considered the reverse situation. He stated that it was equally possible for extraterrestrial organisms to contaminate the earth via space probes. He noted that spacecraft that burned up in reentry presented no problem, but "live" returns—manned flights, and probes such as the Scoop satellites—were another matter entirely. Here, he said, the question of contamination was very great.

His paper created a brief flurry of interest but, as he later said, "nothing very spectacular." Therefore, in 1963 he began an informal seminar group that met twice monthly in Room 410, on the top floor of the University of California Medical School biochemistry wing, for lunch and discussion of the contamination problem. It was this group of five men: Stone and John Black of Berkeley, Samuel Holden and Terence Lisset of Stanford Med, and Andrew Weiss of Stanford biophysics—that eventually formed the early nucleus of the Wildfire Project. They presented a petition to the President in 1964, in a letter consciously patterned after the Einstein letter to Roosevelt, in 1940, concerning the atomic bomb.

University of California

Berkeley, Calif.

June 10, 1964

The President of the United States

The White House

1600 Pennsylvania Avenue

Washington, D.C.

Dear Mr. President:

Recent theoretical considerations suggest that sterilization procedures of returning space probes may be inadequate to guarantee sterile reentry to this planet's atmosphere. The consequence of this is the potential introduction of virulent organisms into the present terrestrial ecologic framework.

It is our belief that sterilization for reentry probes and manned capsules can never be wholly satisfactory. Our calculations suggest that even if capsules received sterilizing procedures in space, the probability of contamination would still remain one in ten thousand, and perhaps much more. These estimates are based upon organized life as we know it; other forms of life may be entirely resistant to our sterilizing methods.

We therefore urge the establishment of a facility designed to deal with an extraterrestrial life form, should one inadvertently be introduced to the earth. The purpose of this facility would be twofold: to limit dissemination of the life form, and to provide laboratories for its investigation and analysis, with a view to protecting earth life forms from its influence.

We recommend that such a facility be located in an uninhabited region of the United States; that it be constructed underground; that it incorporate all known isolation techniques; and that it be equipped with a nuclear device for self-destruction in the eventuality of an emergency. So far as we know, no form of life can survive the two million degrees of heat which accompany an atomic nuclear detonation.

Yours very truly,

Jeremy Stone

John Black

Samuel Holden

Terence Lisset

Andrew Weiss