 Note that Borexino measured neutrinos of several energies; in this manner they have demonstrated experimentally, for the first time, the pattern of solar neutrino oscillations predicted by the theory.Neutrinos can trigger nuclear reactions.By looking at ancient ores of various ages that have been exposed to solar neutrinos over geologic time, it may be possible to interrogate the luminosity of the Sun over time, which, according to the Standard Solar Model, has changed over the eons as the (presently) inert byproduct helium has accumulated in its core.