Anyway, I went over to California, I didn't work full time there. I took a temporary job in Houston at Baylor College of Medicine and used to commute to Jet Propulsion Labs [JPL] from there on a kind of monthly basis. And at first I worked with the engineers and scientists on the surveyor missions projects, but gradually I got drawn in to the work being done by the biologists to detect life on Mars, because they were preparing then to, even as far back as the early 60's, to send some sort-of mission to Mars, mainly to see if there was life there. Everybody believed the science fictional idea of a living planet. And I, of course, got very interested in this. And to my sort-of disappointment, I found that the biologist's experiments, that they were proposing to send for Mars, were exceedingly unrealistic. What they had in mind were experiments that would detect life on Earth as we know it, but they assumed that whatever was on Mars was just the same as there was here. Or, or, worse than that, was the sort of life that grew in the Mojavi Desert, which was just at the back of JPL and very convenient for going to. And I thought, no this won't do at all. So I voiced my doubts and I said, 'I think you need a more general experiment, one that will detect life whatever its form, not one to look for specific things like a given micro-organism or birds or something like that, something very positive'. And they got very annoyed at this. In fact, most of my encounters with biologists lead to them getting very annoyed and I was called over the coals before one of the senior people in JPL, a man called Mcgrublian [?] and he said, 'I hear that you don't think much of the life detection experiments', and I said, 'No, I think they're a waste of money, you shouldn't send them to Mars'. So he said, 'Well, what would you do instead'? which is a kind of question that raises the prospect of hanging. And I said, 'Well, give me three days and I'll come back to you with a general life detection experiment'. And he said, 'Right, I'll expect you here on Friday'. So, I was up against it, and I had to think hard and I thought hard and I came up with a whole set of experiments that Friday and I went into him and I said, 'I think the best experiment you could do to find Mars, life on Mars, would just to analyse the chemical composition of its atmosphere'.          

You see, you would expect a planet to be fairly close to chemical equilibrium at a state that's called a biological steady state. That's, the only thing that's stirring it up is sunlight. And, all the chemicals that have out gassed will be fairly close to equilibrium. But if you've got life on a planet, that can't be because the life will be obliged to use the atmosphere as a source of raw materials and also a place to deposit its waste products. And Mars is a very favourable case because it doesn't have anything an atmosphere. There's no oceans or anything there, as far as we can see. So, it's bound to change the atmosphere if there's life there. And he grew very excited about this, and said, 'That sounds like a great experiment. Go back home', which I was due to do shortly, 'and, you know, send in a report on it'. Well, I sent in a report not only to him, but also a letter to Nature, which was the first paper, I think, on life detection and it was called, The Physical Basis for Life Detection Experiments and it was published in Nature in 1965.

For quite a while NASA got very enthusiastic about it and indeed so enthusiastic that I found myself in almost a sort of unofficial lead experimenter on the next Martian mission, which was called Voyager in those days, and I was getting more and more scared as they were sort of dispersing hundreds of millions of dollars to all sorts of creepy people that were coming out of the woodwork with wonderful experiment. But fortunately, Congress decided they wouldn't send it after all. And I was relieved and able to go back to science.