ftdjt@acad3.fai.alaska.edu (THOMAS DAVID J) (06/26/90)
To anyone who may know: I am trying to find a reference in which Carl Sagan described a hypothetical Martian model in which he stated that Mars may go through long ice ages due to precession. During those ice ages, the Martian environment becomes more favorable for life. I believe the original article was published ca 1971. I found an indirect reference to it in Patrick Moore's GUIDE TO MARS (1977). However, Moore did not give a direct reference to a publication. Any info would be greatly appreciated. Thanks, Dave Thomas