When Daedalus constructed wings for himself and son Icarus to make their daring escape, his choice of materials was limited. And he knew the inherent risks of flying an apparatus crafted with wax too close to the sun.

Utah State University undergraduate Jennifer Albretsen has a much broader and sophisticated range of materials to choose from for NASA's planned Solar Probe satellite, but her concern still centers on the impact of solar radiation. And whereas Daedalus was preparing for low altitude flight and a comparatively short hop from Crete to Sicily, the Solar Probe is expected to travel within three solar radii (3 RS) of the sun's surface. In the course of its journey, the satellite will be exposed to large fluxes of light and charged particles from solar wind, as well as temperatures beyond what Daedalus could have imagined.

"NASA is trying to determine what materials could survive such a mission," says Albretsen, an Undergraduate Research Fellow in physics who is entering her third year at Utah State and was named a 2007 Goldwater Scholar and a 2006-07 Governor's Scholar.

Working with mentors J.R. Dennison, Physics Department professor, and graduate student Ryan Hoffmann in USU's Materials Physics group, Albretsen subjects insulating ceramic materials, including aluminum oxide, barium zirconium phosphate and polyboron nitrate, to specific frequencies of light and measures the resultant current from electrons emitted by each material.

"We place samples in a vacuum chamber," she says, indicating a large, round device that looks like a deep sea diving bell. "When light interacts with a surface, its energy is transmitted to embedded electrons. Often this forces the electrons out of the material, causing it to become charged."

In addition to the Solar Probe, which Hoffmann says resembles "a giant flying ice cream cone," the research trio and colleagues are investigating materials to construct NASA's James Webb Space Telescope, planned successor to the Hubble.

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