The Earth’s magnetosphere is formed by the Sun’s wind passing the Earth. It
surrounds the Earth but is much larger on whichever part forms its local
‘shadow’ or ‘night’ side, where it forms a tail, or magnetotail. The
magnetotail extends over 6,300,000 km.
[...] Every month, at full moon,
the Moon crosses the magnetotail for 6–7 days at about 348,000 km from the
Earth. As revealed by recent space exploration, when the Moon traverses the
magnetotail’s electromagnetic plasma sheet, it attracts a large electrical
charge, thus disturbing the plasma sheet. Ions from the Moon’s surface transfer
to the Earth’s magnetosphere. This in turn can influence the Earth’s electric
and magnetic field by a form of magnetospheric feedback, since the thin current
sheet of the magnetotail has an earthward electric field.
[...] The Moon affects the
Earth’s magnetosphere differently at new moon compared with full moon. At new
moon, on the Sun’s side of the Earth, the Moon does not cross through the
magnetosphere. Instead its lunar wake, formed from the solar wind, is blown
downstream towards the Earth’s magnetosphere in a relatively narrow pathway,
but in a varied way because of the Sun’s 11-year sun-spot cycle and the Sun’s
rotating magnetic field. The latter has two effects. Firstly, Earth experiences
reversed solar polarity when crossing sectors in the interplanetary magnetic
field, typically twice in about 27 days. Secondly, the solar wind travels in a
spiral, so the lunar wake is not usually in direct alignment from the Sun. The
new moon effect from the lunar wake on the Earth’s magnetosphere can be considered
comparable to magnetotail effects at full moon, with evidence of electric
fields, and magnetic fluctuations of up to 5 Hz from the plasma of the penumbra
surrounding the lunar wake."
The greatest change in the electric field potential occurs as the moon crosses into and out of the magnetotail plasma, which occurs 2-3 days before the full moon and 3-4 days after the full moon.
Some of the reported effects of the full moon on animal and plant biology: tree diameter variation reflects a lunar rhythm; reproduction; changes in the stress hormone; epileptic seizures and unexpected deaths increase during full moon; increase of violent and acute behavioral disturbances during full moon, etc.
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