Number 155 (Story #3), December 13, 1993 by Phillip F. Schewe and Ben Stein|
SOLAR WIND SPEEDS are twice as great (800 km/sec) at a latitude of 45 degrees south as in the plane of the ecliptic, new Ulysses measurements show. The Ulysses spacecraft, on its way toward a point beneath the sun's southern pole, does not look at the 5000-K photosphere, the sun we see with our eyes, but rather at the much hotter (millions of K) corona; it studies the magnetic fields and the particles cast out by the sun in a part of the solar system where no probe has ever been before. Ulysses scientists (Ed Smith of JPL and others), who spoke at last week's meeting of the American Geophysical Union in San Francisco, have discovered that shock waves, set up when certain fast gusts of solar wind overtake slower gusts, can accelerate ionized atoms that have entered the solar system from the interstellar medium. It was previously thought that these "anomalous cosmic rays" originated only in the outer precincts of the solar system.