Thus the explosion of stars in the cosmos affects life on Earth

For millennia, and in very different cultures, the idea has been kept alive that the position of the stars and the more or less rare configurations that they manifest over time have a direct influence on earthly events. Astrology, or rather the various and different astrologies that have historically developed, have tried with every effort to translate the regularity of the complicated design of celestial motions into meaning: a phenomenon of geometric and admirable precision, before modern science, was associated with a sense that was important to us, due to the innate tendency of the human being to seek agents and meanings for ourselves in very regular phenomena. Since Newton, astrological beliefs have become obsolete, and have been gradually surpassed in explanatory and predictive capacity by modern astronomy, despite the survival of various astrological beliefs and their esoteric derivations, as in the case of biodynamics; however, scientific knowledge has illuminated some real influences of cosmic events on the life of our planet.

The influence of the phases of the moon on the behavior of various organisms is the most obvious and best characterized example; less known, however, is the fact that even cosmic events that occur at much greater distances from the Earth can have a direct influence on living organisms. In a very recent article, we have a particularly interesting example of this type of influence. In short, an article published in Ecology and Evolution documented a possible direct influence in the last half billion years of catastrophic events, which fortunately occurred far from us, on the biodiversity of marine life. The new study reveals a big surprise: the variable number of large-mass stars exploding (supernovae) at non-excessive distances from our planet is strongly correlated with changes in the biodiversity of marine genera (the taxonomic rank above the species) during the last 500 millions of years. The correlation appears after normalizing the marine diversity curve as a function of the extent of shallow water that occurred over geological eras, because this factor is known to strongly control the diversity of marine life. How can we explain the very specific and close correlation between the trend of marine biodiversity documented by fossils and the explosion of supernovae, documented by their remains in the space around us?

A possible answer comes from the observation that, in periods with a greater number of explosions, an average colder climate was observed on our planet, with a large difference in temperature between the equator and the polar regions. This type of climate results in stronger winds, mixing of the oceans and transport of nutrients essential for life in surface waters along the continental shelves. Now, the authors reason, when supernovae explode, they produce cosmic rays, which are elementary particles with enormous energies. Cosmic rays travel to our solar system, where some end their journey by impacting the earth’s atmosphere. Previous studies have shown that this impact is a primary source of ions, which help form and grow the aerosols required for cloud formation. Since clouds can regulate the solar energy reaching the earth’s surface, the amount of ions generated by the rays originating from supernovae has the potential to influence climate. It was already known, however, that substantial climatic changes have occurred when the intensity of cosmic rays has changed significantly over millions of years. The mechanism illustrated is obviously hypothetical, based on the coordinated interpretation of a number of known facts, but not directly proven; however, it is plausible and compatible with the available observations, so the new paper concludes that supernovae are vital for the biological productivity of the seas by influencing the transport of nutrients through climate change.

Many times we have discussed on these pages how life was triggered by a biochemistry that originated everywhere in the cosmos, starting from the combination into complex molecules of the chemical elements generated in stellar forges and other cosmic objects; we also all know how great catastrophes caused by comets and asteroids can change the course of evolution, destroying entire ecosystems and making groups of organisms disappear; moreover, as mentioned above, the Moon is used to regulate various activities by many biological organisms. Now, if this latest study is confirmed and strengthened, we have for the first time the opportunity to test a scientific theory that sees a persistent and strong influence on the evolution of life on our planet by objects at very high distances: for example, an accurate estimate of the amount of cosmic rays that have invested our planet in geological eras can be obtained independently with different methods, and the weight of their effect in the alteration of the climate can be determined in many different ways. And this is, precisely, the role of science: to provide hypotheses of mechanisms consistent with the observed facts, which can be tested, unlike the traditional superstitions that some, even today, persist in preferring to the much more fascinating scientific descriptions of ‘universe.