Thursday, February 25, 2010

Cosmic Rays, Climate, And The Origin Of Life

Wow. That's a really fully-loaded topic, isn't it? But that's the title of a very informative article in the March 2010 issue of Cern Courier.

This phenomenon has a possible relevance to the origin of life on Earth. The current favourite models for this origin are either on comets in outer space, as Fred Hoyle and Chandra Wickramasinghe suggested, or in the black smokers or alkaline vents that result from volcanic activity in the deep oceans. However, another possibility follows from the famous early experiments of Stanley Miller and Harold Urey, in which they passed a spark through a mixture of liquids (water, methane, ammonia, etc) – the “prebiotic soup". This resulted in the appearance of the basic building blocks of life, such as amino acids, RNA and monomers. One problem, however, was that the available spark energy, from lightning, was thought to be inadequate.

This is where the long-term variability of EAS rates may have relevance. We have shown that there should have been periods during which the EAS rate was higher by orders of magnitude than at present (Erlykin and Wolfendale 2001). Our theory is based on the statistical nature of supernova explosions, which are thought to be the originators of high-energy cosmic rays. Figure 3 shows how, from time to time, periods of high cosmic-ray intensity of tens of thousands of years will occur, as a nearby supernova explodes. This will lead to high lightning rates. One of these, occurring at around 4 Gy before the present (a not unlikely occurrence), could have led to the formation of the building blocks of life via the Miller-Urey mechanism. Life could then have evolved from such a start.

There ya go! You and could have been initiated by cosmic rays! :)


No comments: