"Lie on Mars? The case for a cosmic heritage" is a well researched book authored by the late Sir Fred Hoyle and Professor N. Chandra Wickramasinghe. In this book, the authors essentially develop the theme laid down in their two previous books "Diseases from Space" (Sphere; New Ed edition 22 Oct 1981) and "Lifecloud" ( Sphere; New Ed edition 25 Oct 1979) that life had an extraterrestrial rather than a merely localised terrestrial origin.
Hoyle and Wickramasinghe begin by examining the conditions for life in our solar system. While complex forms of life such as plant and animal species are ruled out, the authors do not dismiss the possibility of simpler microbial life forms surviving in places such as the higher parts of the Venusian atmosphere, the Martian soil and on some of the satellites of Jupiter and Saturn. In the same chapter, consideration is given to the number of Earth - like worlds that may exist on extra-solar planets and how many of these may have developed advanced life and advanced technological civilisations.
When arguing the case for Panspermia ( or "Cosmicrobia" as the authors prefer to term the concept ) Hoyle and Wickramasinghe point out the fallacies in the arguments against this theory. That microorganisms display an immense capacity to survive ultraviolet light is a fact used by the authors to give substance to their contention that microorganisms can survive the ravages of interstellar space and move from one star system to another. Graphs which show a parallel between the known spectral emission and absorption curves of bacteria and those of interstellar gas clouds are used to strengthen the theory of Panspermia ( Cosmicrobia ) Comets are considered by the authors as being the vehicles by which life is brought to planets. As comets, in their highly elliptical orbits, approach the sun, they evaporate some of their material - the familiar "tail" of the comet. Much of this material, argue the authors, is biological. As the Earth passes through the debris left by evaporated cometary material, it picks up some of it this debris in the form of viral and bacterial matter.
One of the most interesting themes of this work is the authors' challenge to the classical Darwinian theory of the origin of life. They mathematically prove that life could not have begun on Earth as the resources of a single planet are insufficient to allow for all the possible combinations of the base pairs of DNA needed in order to produce the great variety of life forms. It is essential that life be a cosmic rather than a mere Earth bound phenomenon. It is also of interest to note how Hoyle and Wickramasinghe tie in Panspermia with the Steady State Theory. Just as the Universe, according to this theory, has always existed, so too has life. In arguing the case for Steady State/ Panspermia theory, the authors state - "which came first, the blueprint for the enzyme or the enzyme itself".
The final part of this book examines the case for various diseases such as influenza, the common cold, mumps and whooping cough being extraterrestrial in origin and brought to the Earth by comets. By using climatological and meteorological data, the two authors present a convincing case for the extraterrestrial origin of influenza outbreaks. They also link this theory of the origin of diseases to their main Panspermia theory by contending that it is from viral and bacterial matter shed by comets that the Earth receives fresh inputs of DNA in order to drive the engine of evolution.
As in all their other works, Sir Fred Hoyle and Professor Wickramasinghe never cease to be controversial. Yet, it is only by controversy that science and technology - and indeed, society itself - can progress. In the epilogue of "Life on Mars", the authors show a compelling connection between major civilizational events and cometary impacts on the Earth. So in terms of the health of mankind and even, dare it be said, the very survival of the human species, we may well be being subliminally advised by the authors of this book to start looking upwards far more often.