Quest for a Creatorless Origin of Life - 8
Those involved in this highly organized quest found it necessary early in their work to clearly define what life is. One of them defined life as “a self-sustained chemical system capable of undergoing Darwinian evolution.” This views each form of life to be a chemical system. It is able to autonomously grow and feed itself by collecting material and energy, and can produce variation (e.g., differing colours) over time.
Many of those evolutionists who have been searching for the origin of life admit that the earliest life form could not have looked anything like the simplest existing living cell, with its whole array of chemical factories and highly complex chemicals. Nor could the first life have DNA, that exceedingly intricate genetic mechanism of modern living things.
This forced the conclusion that the first living cell could not have been formed in a single step from the chemical components of ocean, atmosphere and rock - that it had to be the result of a whole series of chemical reactions over a long time. What chemical reaction occurred in each step? As we noted last time, the conclusion is that no trace can be found of those imagined intermediate steps which they were so hopeful of discovering that led to the formation of living cells as the now exist.
But that process is tied to that Image which resides in the Temple of their faith, whose name is Emergence - the as yet undiscovered cause of “the inevitable direction of increasing chemical complexity.” Many of those involved in the search for an origin of life - a process which was unassisted by the manipulation of an external intelligence - expect to find Emergence at work in any place where conditions are conducive to its operation, whether on earth or elsewhere.
The planet Venus, in the next orbit towards the sun, has a surface temperature above that of the melting point of lead, and contrary to recent claims is not a promising place in that regard,.
Mars, while orbiting further from the sun than Earth, has been seen as a good place for life to have emerged. In search for that life, immense amounts have been spent in the last sixty years, sending various probes to the red planet.
These probes have suggested that Mars once had water on its surface at higher average temperature than the current range of 35○C to -127 ○C. This has led to the expectation that life could well have emerged there a long time ago. There ought therefore, in that case, to be some fossil evidence of that life, and possibly some surviving life below the surface.
Between 1964 and 1971 four Mariner probes passed close over Mars, revealing the surface as an endless desert. Following this, Viking 1 was sent for a soft landing on Mars and to look for evidence of life - but the results were contradictory.
In the meanwhile it has been concluded that the landings of probes on Mars have already contaminated that planet with microbes from the earth. This will complicate any further attempts to establish that some form of life had previously existed there. Any future claims that emergence had occurred there would be met with serious doubts.
Undaunted, those working in the quest for spontaneously generated life have turned to searching the heavens for likely exoplanets. These planets are vast distances from Earth, and a probe would need to travel near the speed of light to reach the closer ones in a human lifetime.