Historical Earth Ellipsoids
The following table lists 9 ellipsoids which (except Clarke's) were the best estimation of the Earth's figure when they were published:
| Name | Equatorial axis (m) | Polar axis (m) | Inverse flattening, |
|---|---|---|---|
| Delambre, France 1810 | 6,376,985.0 | 308.6465 | |
| Airy 1830 | 6,377,563.4 | 6,356,256.913224 | |
| Bessel 1841 | 6,377,397.155 | 6,356,078.963 | 299.1528128 |
| Clarke 1866 | 6,378,206.4 | 6,356,583.8 | 294.9786982 |
| Helmert 1906 | 6,378,200.0 | (close to WGS84!) | 298.30 |
| International 1924 | 6,378,388.0 | 6,356,911.9 | 297.0 |
| Krassowski 1940 | 6,378,245.00 | (for Eastern Europe) | 298.3 |
| Internat. 1967 Luzern | 6,378,165.00 | (incl. Sat.Geodesy) | 298.25 |
| GRS 80 | 6,378,137.00 | 6,356,752.31414 | 298.257222101 |
| WGS 1984 | 6,378,137.00 | 6,356,752.3142 | 298.257223563 |
Read more about this topic: Earth Ellipsoid
Famous quotes containing the words historical and/or earth:
“Some of us still get all weepy when we think about the Gaia Hypothesis, the idea that earth is a big furry goddess-creature who resembles everybody’s mom in that she knows what’s best for us. But if you look at the historical record—Krakatoa, Mt. Vesuvius, Hurricane Charley, poison ivy, and so forth down the ages—you have to ask yourself: Whose side is she on, anyway?”
—Barbara Ehrenreich (b. 1941)
“Some of us still get all weepy when we think about the Gaia Hypothesis, the idea that earth is a big furry goddess-creature who resembles everybody’s mom in that she knows what’s best for us. But if you look at the historical record—Krakatoa, Mt. Vesuvius, Hurricane Charley, poison ivy, and so forth down the ages—you have to ask yourself: Whose side is she on, anyway?”
—Barbara Ehrenreich (b. 1941)