Ithaca, NY—Last fall Beth Ellen Clark, an assistant professor of physics at Ithaca College, joined an international scientific team in Japan to study data on Itokawa, a peanut-shaped asteroid more than a million miles from earth. In 2005 the hovering probe that transmitted the data landed on the 500-yard-long Itokawa to take samples and is now on its way back to earth, making the spacecraft the first in history to attempt a sample return from an asteroid. According to Clark, what the probe brings back, coupled with the data she and her colleagues have already studied, will have significant implications for both scientists and laymen.

 

“Asteroids are celestial fossils in the sense that they haven’t changed much chemically since they were formed in the earliest days of our solar system,” Clark said. “This mission, therefore, is like an archaeological dig but undertaken in space. By discovering the geology and chemical composition of this asteroid, we can gain great insights into how the solar system, along with the earth, came into being.”

 

The findings from the asteroid study also have a practical side.

 

“There are more than 100,000 asteroids out there, and, of course, there’s the chance that one of them could collide with the earth,” Clark said. “By learning more about the internal structures of asteroids, we’ll be better able to defend ourselves. For example, if the asteroid is dense, mitigation scenarios might include trying to blow it up. But if the asteroid is extremely porous, it might be easier to deflect it.”

 

A joint project between NASA and Japan’s Institute of Space and Astronautical Science, the asteroid study began in 2003 with the launch of the spacecraft—named Hayabusa, after the Japanese word for “peregrine falcon.” Clark’s role was to use infrared spectroscopy techniques to study the asteroid’s composition. Her research resulted in an article, “Developing Space Weathering on the Asteroid 25143 Itokawa,” published by Takahiro Hiroi, Clark and six others in the September 2006 issue of Nature.

           

“Since different minerals absorb various wavelengths of light differently, scientists can examine the spectral absorptions on an asteroid’s surface, compare them to the spectra of minerals measured on earth, and have a good chance of identifying the asteroid’s mineral and chemical composition,” Clark said.

           

So far, the asteroid is turning out to be much less dense than expected, indicating it might be a loose collection of space rubble.

 

“That implies that when minerals and rocks were forming out of the earliest matter in the solar system, they were capable of combining into objects as big as this asteroid, even though they were forming in a very chaotic, dynamical environment,” said Clark. “The question remains, How did objects the size of planets form in such disruptive conditions? We’ll know more when Hayabusa comes back to earth with the samples.”

 

For more information on the Hayabasu mission and to view images of the spacecraft, visit http://neo.jpl.nasa.gov/missions/hayabusa.html. Visit www.isas.jaxa.jp/e/snews/2006/0602.shtml for images of the asteroid.

 

To arrange an interview with Beth Ellen Clark, contact Keith Davis, assistant director of media relations, at (607) 274-1153 or kdavis@ithaca.edu.