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I am looking for data sets which clock the time and precise location of free falling bodies in a vacuum. I have been told that the acceleration of gravity is not absolutely 100% uniform, and I would like to examine the data sets as to this question, particularly as to minute discrepancies. The more the better. Any help in locating this raw data would be very appreciated.

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I doubt the data you're looking for exists; at least, not in any comprehensive form. Though there are some gravimeters that work by doing what you say - measuring the timing of an object in vacuum free fall - they are cumbersome and require the device to be fixed firmly in one spot. The gravimeters used in geoid surveys are usually relative, that is, they use springs or magnetic fields to measure the force on a test mass.

There are two reasons the strength of earth's gravitational field varies with location: the variation in altitude of the earth's surface and the variation of the density of the earth. The latter is the smaller and more interesting effect, and so most comprehensive geoid surveys are done by satellites that orbit at a fixed radius. As a result, these surveys are very expensive (not to mention very valuable for prospecting purposes) so you're probably not going to get access to most of the data out there without laying out some serious cash.

However, the European Space Agency recently completed a mission called the Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) that did a gravitational survey and some of their data is freely available for non-commercial purposes. You can register here and request access. I don't know what the form the data takes, i.e., how "raw" it is. An important note, though: satellites are in freefall, and hence the raw data of a mission like the GOCE is measurements of the graviational gradient from place to place. In other words, the variation of very small tidal forces. The relative strength of the gravitational field itself must be reconstructed from that based on the satellite's altitude.

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