Polar Shift
The "Pole Shift hypothesis" is based on
geologic evidence that the physical north and south poles of Earth
have not always been at their present-day locations; in other words,
the axis of rotation had been "shifted". Pole shift theory is almost
always discussed in the context of Earth, but other solar system
bodies may have experienced axial reorientation during their
existences. Introduced by History Professor, Charles H. Hapgood, whose fascination with geography and ancient maps led to
his re-discovery of the Piri Reis Map. This hand drawn Turkish naval
map had been gathering dust since the early 1500's, its significance
unrealized. On closer scrutiny, Hapgood observed evidence of
spherical trigonometry and a detailed knowledge of global
geography-- including the coastline of Antarctica at a remote time,
when it was free of ice. The map had been drawn just a few years
after Columbus visited the Americas. The cartographer, Admiral Piri
Reis, described his world map as having been drawn from "very old"
reference maps. It appeared as if some ancient, forgotten
civilization had risen to these capabilities, and then had
disappeared. The identity of these ancient mariners begged to be
discovered.
Watch an introduction to Polar Shift
The pole shift hypothesis is the hypothesis that the axis of
rotation of a planet has not always been at its present-day
locations or that the axis will not persist there; in other words,
that its physical poles had been or will be shifted. The Pole shift
hypothesis is almost always discussed in the context of Earth, but
other bodies in the Solar System may have experienced axial
reorientation during their existences.
Pole shift hypotheses are not to be confused with plate tectonics,
the well-accepted geological theory that the Earth's surface
consists of solid plates which shift over a fluid asthenosphere; nor
with continental drift, the corollary to plate tectonics which
maintains that locations of the continents have moved slowly over
the face of the Earth, resulting in the gradual emerging and breakup
of continents and oceans over hundreds of millions of years.
Pole shifts are a cataclysmic inversion of the planet's axis of
rotation, up to 180 degrees; a sudden slippage of the planet's solid
crust around the molten core. There are several major scientists of
this century that also expose this concept as an event that has
happened before in Earth's past.
Geographic axis: man-made arbitrary north-south fixed reference that
determines lines of longitude and latitude, and the geographic North
and South Poles.
Axis of instantaneous rotation: the true astronomical axis; the
rotation axis. The line drawn through the Earth about which it is
actually rotating at any point in time. The points where the line
cuts through the earth's surface are called the "rotation poles";
the visualized extension of the north axis line in space currently
points to the star Polaris, the North Star.
Axis of maximum moment of inertia = the axis of figure: because the
Earth is not a perfect sphere, but is physically an oblate spheroid,
the position of the axis of figure is not a precise constant, but is
affected by the constant change in the earth's distribution of total
mass: (ie, by ocean tides, atmospheric conditions, plate tectonic
movements, etc.).
The combinations, and movements, of these masses with gravitational,
centrifugal and orbital velocity vector forces, create what we call
the equatorial bulge, and thus, the axis of figure. If the Earth
were a perfect sphere, there would not be such an axis. The angular
difference between the astronomical axis and the axis of figure,
called a "nutation", causes an Earth orbital spirical oscillation,
known as the famous Chandler "wobble". The equatorial bulge, the
rotation axis' angle of inclination to the ecliptic plane, the
gravitational tidal forces of the Sun, Moon and planets, have an
affect on the Earths' orbit that produces the famous precession of
the equinoxes.
Axial Tilt: the ecliptic is the plane of the Earth's ellipsoidal
orbital path around the sun; the rotation axis is currently inclined
to the ecliptic by an angle of 23.5 degrees: this is called the
obliquity, or tilt, of the axis. It is this axial tilt that causes
our annual seasons. Due to orbital dynamics, the obliquity varies
between a minimum of 21 degs. 39 mins. and a maximum of 24 degs. 36
mins. over a 41,000 year cycle. The axial tilt's rate of change,
(angular differentiation), is currently measured as .013 degs. per
century.
Geomagnetic axis: not to be confused with the geographical axis, as
it often times is. The Earth's magnetic field (whose real source is
still an ongoing scientific mystery, but generally attributed to the
interactions between the interior molten convection currents and the
nickel-iron core, generating an electromagnetic force field, coupled
with the rotational and orbital forces), itself has, by its own
lines of force through space, the magnetosphere, a north- south
axis. At present, the angular difference between geographic and geo-
magnetic north poles is about 11 degrees.
Through paleomagnetism, (the study of the magnetic properties of
rocks), scientists now have solid proof that the earth's magnetic
field, and thus the geomagnetic north and south poles, have reversed
itself many times in the past. Magnetic field polarity reversals are
magnetic poleshifts. The geologic record also shows that the
strength of the magnetic field varies widely in time, and fluctuates
wildly during field reversals, sometimes dropping to zero gauss
strength; ie: the field vanishes, disappears! It is also a proven
fact that the magnetic poles wander, literally zig-zagging around
its axis.
