Polar Motion
Polar motion of the Earth is the movement of the point where Earth's rotational axis intersects its surface. This is measured with respect to a reference frame in which the solid Earth is fixed (a so-called Earth-centered, Earth-fixed or ECEF reference frame). This variation is only a few meters.
Read more about Polar Motion: Analysis, Causes, Basic Principles, Observations, Data
Famous quotes containing the words polar and/or motion:
“In time your relatives will come to accept the idea that a career is as important to you as your family. Of course, in time the polar ice cap will melt.”
—Barbara Dale (b. 1940)
“It is the fixed that horrifies us, the fixed that assails us with the tremendous force of mindlessness. The fixed is a Mason jar, and we can’t beat it open. ...The fixed is a world without fire--dead flint, dead tinder, and nowhere a spark. It is motion without direction, force without power, the aimless procession of caterpillars round the rim of a vase, and I hate it because at any moment I myself might step to that charmed and glistening thread.”
—Annie Dillard (b. 1945)