The South Atlantic Anomaly (SAA) is an area where the Earth's inner Van Allen radiation belt comes closest to the Earth's surface dipping down to an altitude of 200km (124mi). This leads to an increased flux of energetic particles in this region and exposes orbiting satellites to higher than usual levels of radiation. The effect is caused by the non-concentricity of the Earth and its magnetic dipole, and the SAA is the near-Earth region where the Earth's magnetic field is weakest.
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Famous quotes containing the words south and/or atlantic:
“The Great South Beach of Long Island,... though wild and desolate, as it wants the bold bank,... possesses but half the grandeur of Cape Cod in my eyes, nor is the imagination contented with its southern aspect.”
—Henry David Thoreau (1817–1862)
“They commonly celebrate those beaches only which have a hotel on them, not those which have a humane house alone. But I wished to see that seashore where man’s works are wrecks; to put up at the true Atlantic House, where the ocean is land-lord as well as sea-lord, and comes ashore without a wharf for the landing; where the crumbling land is the only invalid, or at best is but dry land, and that is all you can say of it.”
—Henry David Thoreau (1817–1862)