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:
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