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May I know how scientist measure the radius of the earth?

And how accurate it is??

And how accurate it is??

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May I know how scientist measure the radius of the earth?

And how accurate it is??

And how accurate it is??

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http://opal.physik.uni-bonn.de/~mkobel/pos/deleg/zapp/zapp1.htm [Broken]

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russ_watters

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LURCH

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YES! His name is spelled "Eratosthenes", and he (in any inertial frame of reference) da man!!Originally posted by russ_watters

A more modern method used to independently verify this measurement is satellite VLBI. "VLBI" stands for Very Long Baseline Interferometry, and involves two satellites looking at a common object. The two satellites can be placed at a known altitude (using radio altimeters), with a known difference in global position. For example, they could be placed 90

Now, quasars have a signature EM wave pattern. Both satellites will see this distinctive pattern, but the satellite directly over the pole will see it first. By measuring the difference between the two wave patterns (how they "interfere" with one another) we can determine how far apart the two satellites are. This gives us an extrasolar source for our measurement. Submitting the information from this alternate source to the same geometry used by Eratosthenes, we can get independent verification of his measurement.

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Integral

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I tried it from Yaquina Head on the Oregon coast.

We must have made some canceling errors because we came up with a result much closer then I believed possible. It's been 20+ yrs so I really can't remember the specifics.

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