Measuring The Gravity Gradient
Put simply gravity measurements are a reflection of the earth’s gravitational attraction, its centrifugal force, tidal accelerations due to the sun, moon, and planets, and other applied forces. Gravity gradiometers measure the spatial derivatives of the gravity vector. The most frequently used and intuitive component is the vertical gravity gradient, Gzz, which represents the rate of change of vertical gravity (gz) with height (z). It can be deduced by differencing the value of gravity at two points separated by a small vertical distance, l, and dividing by this distance.
The two gravity measurements are provided by accelerometers which are matched and aligned to a high level of accuracy.
Read more about this topic: Gravity Gradiometry
Famous quotes containing the words measuring the, measuring and/or gravity:
“... there is no way of measuring the damage to a society when a whole texture of humanity is kept from realizing its own power, when the woman architect who might have reinvented our cities sits barely literate in a semilegal sweatshop on the Texas- Mexican border, when women who should be founding colleges must work their entire lives as domestics ...”
—Adrienne Rich (b. 1929)
“As an example of just how useless these philosophers are for any practice in life there is Socrates himself, the one and only wise man, according to the Delphic Oracle. Whenever he tried to do anything in public he had to break off amid general laughter. While he was philosophizing about clouds and ideas, measuring a flea’s foot and marveling at a midge’s humming, he learned nothing about the affairs of ordinary life.”
—Desiderius Erasmus (c. 1466–1536)
“Here I sit down to form characters. One I intend to be all goodness; All goodness he is. Another I intend to be all gravity; All gravity he is. Another Lady Gish; All Lady Gish she is. I am all the while absorbed in the character. It is not fair to say—I, identically I, am anywhere, while I keep within the character.”
—Samuel Richardson (1689–1761)