PASADENA, Calif. The Ulysses spacecraft will begin on Friday its second pass by the suns south polar region, a journey that should reveal a far different star than it did during a previous swoop-by in 1994.

The latest passage will take the European Space Agency (ESA) probe to a maximum of 80.2 degrees southern latitude, allowing it to observe the suns south pole as it approaches its period of increased activity, called the solar maximum.

During solar max, heightened space weather can spark geomagnetic storms here on Earth, interfering with radio transmissions, affecting power grids and producing colorful auroras at high latitudes. At present, solar storms are already numerous and the high-latitude solar wind, or stream of charged particles blowing away from the sun, is chaotic and blustery, according to ESA scientists.

Ulysses previously observed the sun during the relatively calm solar minimum between 1994 and 1996. When completed, the new observations should give a dramatically different global view of our star, rounding out Ulysses coverage of a full, 11-year solar cycle.

"Ulysses has been making continuous observations of the sun and heliosphere for the last 10 years," said Edward Smith, the U.S. project scientist for Ulysses at NASAs Jet Propulsion Laboratory. "The scientists involved are still as enthusiastic as ever and are looking forward to discovering lots of new things as the sun acts up."

After its four-month tour above 70 degrees south latitude, Ulysses' orbit will carry the craft over the sun's equator in early 2001, turning its attention to the suns northern hemisphere. It will begin its passage over the solar north pole on September 3, 2001. Contingent on mission funding and the spacecrafts health, Ulysses will return to the suns south pole in November 2006.

The Ulysses mission is a joint ESA-NASA endeavor, with the Americans supplying radio-tracking and data-management operations, as well as some of the scientific instrumentation aimed at characterizing the heliosphere as a function of solar latitude.

The 810-pound (365-kilogram) spacecraft was launched from Space Shuttle Discovery in October 1990.

In 1992 it swung by Jupiter in a move designed to accelerate it out of the ecliptic plane the plane in which most planets travel around the sun and into higher latitudes. That unique trajectory made Ulysses the first spacecraft ever to be launched into an orbit outside that plane.