South Pole Flyby

On February 7, 2007 the ESA-NASA Ulysses spacecraft flew over uncharted territory - the mysterious South Pole of the sun.

"We must always remember with gratitude and admiration the first sailors who steered their vessels through storms and mists, and increased our knowledge of the lands … in the South." - Roald Amundsen

Less than one hundred years ago, the south pole of Earth was a land of utter mystery. Explorers labored mightily to get there, fighting scurvy, wind, disorientation and a fantastic almost-martian cold. Until Roald Amundsen and Robert F. Scott reached the Pole in 1911 and 1912, it was terra incognita.

Credit: David Hardy / ESA

Ulysses, an artist's impression.

The situation is much the same today—on the sun.

"The sun's south pole is uncharted territory," says solar physicist Arik Posner of NASA headquarters. "We can barely see it from Earth, and most of our sun-studying spacecraft are stationed over the sun's equator with a poor view of higher latitudes."

There is, however, one spacecraft that can travel over the sun's poles: Ulysses, a joint mission of NASA and the European Space Agency. And Ulysses is making a rare South Pole flyby.

"On February 7th, the spacecraft reached a maximum heliographic latitude of 80oS—almost directly above the South Pole," says Posner who is the Ulysses Program Scientist for NASA.

Solar physicists are thrilled. Ulysses has flown over the sun's poles only twice before--in 1994-95 and 2000-01. The flybys were brief, but enough to prove that the poles are strange and interesting places.