To: J. Lederberg   Date: 2/24/61
From: F.R. Mayo
Your tracer method of finding cyclohexane [. . . ] acid is a sound one, but my main intent is in getting  enough cyclic treiner so that a sensitive analysis is not needed.  I looks as if my radiation experiements are stalled for a few weeks for lack of assistance.
As for your question about methan ices in comets and their polymerization, I am no authority on these matters, but I will do the best I can.  The vapor pressure of methane is 1 mm. of Hg at 67.3 degrees, 10 mm. at 77.7 degrees K.  If our moon isn't big enough to hold an atmosphere, I don't see how a comet can.  Even at 10-50 degrees K I would expect a comet to lose methane in outer space.  If it is close enough to absorb much solar radiation, its temperature is inevitably much higher.
From the posulate that comets are composed mainly of frozen methane ices, it follows immediately that the polymerization of methane must be inefficient or there wouldn't be so much methane there.  Methane is the alkane which is thermodynamically most stable.  N-hile steady radiation might shift the "equilibrium" slightly toward higher alkanes, it will also prevent them from accumulating.
In summary, I am very dubious about getting much higher alkanes from methane in comets, but I leave it to you as to how good my reasons are.