For almost four decades, scientists have puzzled over portions of the solar wind that were traveling twice as fast as anyone could explain. Now, thanks to observations made by a recent Space-Shuttle mission and a spacecraft built to watch the sun, solar scientists may have an answer.

Charged particles, some of which travel as fast as 500 miles per second and make up much of the solar wind, may be surfing on waves of the Suns magnetic field. The wind can be seen in the Suns corona, the electrically-charged outer reaches of its atmosphere. This area is only visible during a total eclipse of the Sun by the moon, when it appears as a shimmering halo around a black disk.

Instruments aboard the international Solar and Heliospheric Observatory (SOHO) and NASAs Spartan 201, which was flown last fall from Space Shuttle Discovery during John Glenns historic return to space, have made detailed observations of the motions of solar wind ions.

"We were quite surprised to find that heavier oxygen ions actually moved faster than lighter hydrogen ions," said Steven Cranmer of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. "The best explanation for this is a magnetic field line that wiggles back and forth in the same amount of time that oxygen ions take to spiral around it. Just as a child riding on a swing moves higher if someone pushes with the right rhythm, the resonant magnetic waves give a boost to the oxygen ions," he said.