Nuclear reactor at the core of the Earth! - A solution to the riddles of relative abundances of helium isotopes and geomagnetic field variability

摘要

The quest for the origin and understanding relative abundances of ~3He and ~4He isotopes and the origin and cause for variability of geomagnetic field has been a continuing activity. Helium gas is attributed to primordial origin or to radioactive decay of various unstable isotopes. The geomagnetic field attributed to a geodynamo is observed to show variability and also reversibility in its sign. Can there be a common origin or cause for these and other geological observations? Helium, the lightest of the noble gases, was identified in the Sun in 1868, during a solar eclipse in India. A spectrometer was used for the first time in the study of the chromosphere around the Sun, the chromosphere's spectrum among other bright stripes, contains a yellow line that, at the time, was thought to correspond to sodium. The French astronomer Janssen proved that the yellow line did not belong to sodium, but was probably the line of a new element. Lockyer and Frankland confirmed Janssen's results and proved that the bright yellow line could not have an earthly origin. Frankland proposed the name 'helium' after the Greek word 'Helios' for Sun. This stripe was later detected in the spectra of many other stars and, in 1882, Palmieri observed it in gases erupting from Vesuvius.