Herndon suggested that the composition of the
inner core of Earth is
nickel silicide; the conventional view is that it is iron–nickel alloy. In 1992, he suggested "
georeactor" planetocentric
nuclear fission reactors as energy sources for the
gas giant outer planets, as the energy source and production mechanism for the geomagnetic field and
stellar ignition by
nuclear fission. Scientists who have scrutinised these ideas have challenged the underlying assumptions and proposed mechanisms. In a paper on the nuclear reactor hypothesis, Schuiling argues that 'it is unlikely that nuclear georeactors ... are operating at the Earth's centre'. In 2005, Herndon postulated what he calls
whole-earth decompression dynamics, which he describes as a unified theory combining elements of
plate tectonics and
Earth expansion. He suggests that Earth formed from a
Jupiter-sized
gas giant by catastrophic loss of its gaseous atmosphere with subsequent decompression and expansion of the rocky remnant planet resulting in
decompression cracks at
divergent continental margins which are filled in by basalts from
mid-ocean ridges. Recent measurements of "
geoneutrino" fluxes in the KamLAND and Borexino experiments have placed stringent upper limits on Herndon's "
georeactor" hypothesis on the presence of an active nuclear fission reactor in the Earth's inner core, so that such reactor would produce less than 3 TW. == Chemtrail theory proponent ==