Neutrinos from the Sun, pollution of the Galaxy by the products of stellar nucleosynthesis and the terrestrial ice ages

One of the possible explanations of Davis' observational results on solar neutrinos is the hypothesis stating that the metal abundance Z is extremely low throughout the whole Sun, with the exception of its surface layers. Accretion of interstellar matter during the voyage of the Sun in the Galaxy should be responsible for the higher abundance of the heavy elements of the solar surface. The matter which was accreted by the Sun might have contained a higher percentage of the heavy elements than the matter out of which the Sun was born. Periods of enhanced accretion during the passage of the Sun through the spiral arms of the Galaxy can be ralated to the successive ages in the history of the Earth. (author)