April 18, 2006

Hawaii Researchers Seek Interstellar Wind

HONOLULU (AP) - Hawaii astronomers are analyzing data they gathered from the Sahara desert to find evidence of interstellar wind blowing through the solar system.

Six University of Hawaii scientists traveled to Libya to view the sun's outer corona for four minutes and six seconds during a total eclipse March 29.

They used specialized imaging cameras and an infrared spectrograph to look at the sun's outer corona, which is only visible during a total solar eclipse.

Temperatures on the sun are usually millions of degrees, but the outer regions of the sun have a cooler gas that is only a few thousands of degrees, said Jeff Kuhn, associate director of the university's Institute for Astronomy's Maui Division.

"It means there is a wind blowing through the solar system through interstellar space. It impinges on the earth and also impinges on the sun," he said.

Most of the instruments gathered information from infrared wavelengths, but one tool looked at the sun in visible light.

"What we were after was to try to understand something about the cool part of the hot corona, which is normally millions of degrees," he said. "We were looking to find that wind as it passed by the sun."

The researchers also gathered large parts of the infrared spectrum, which will be used at the Advanced Technology Solar Telescope planned for Haleakala on Maui.

"That we managed to get to the eclipse site was a miracle and an incredible feat on the part of Libya," said astronomer Shadia Habbal, who organized the expedition.

Habbal thanked Libya for flying them to the desert on a military plane and helicopters, and for organizing a conference two days before the event.

More than 200 people gathered at the observation site in the southern half of Libya in the middle of the desert, she said.