Wanted: Tougher Skins

The University of Chicago just received a large federal grant to study and develop next-generation space materials.

05/14/2001

by Paul Morledge

Steven Sibener is the project leader of the University of Chicago's new Center for Materials Chemistry in the Space Environment. University of Chicago

Space telescopes and exploratory probes bring astronomical phenomena ever closer to those living under Earth’s protective atmosphere. But these extraterrestrial extensions of our eyes need their own form of defense against a multitude of space hazards such as corrosive cosmic rays, the searing solar wind, and speeding space debris. Consequently, the United State’s Department of Defense has just awarded the University of Chicago a $5 million grant to develop new and improved materials that will endow space instruments with greater protection and long-term performance.

A commonly held misconception is that space is nothing more than a dark, quiescent void that one has to travel through to get to the stuff that really matters you know, astronomical objects of interest like planets and stars. The reality is much harsher. In fact, this seemingly passive realm can often be downright hostile and destructive. Charged particles of the solar wind, intense ultraviolet radiation, crashing space debris, and speedy atomic nuclei(cosmic rays) launched by distant supernovae explosions all eat away at the material skins and machinery of Earth-orbiting telescopes, satellites, and spacecraft.

The synergistic effects of these space hazards really stymie scientists. It's one thing to understand what happens when electrons, ions, free-radical oxygen atoms or ultraviolet radiation separately attack manmade space materials, but quite another to comprehend how they strike in combination.

Launched in 1984 by the space shuttle Challenger, LDEF was mounted with a variety of metals, polymers, and ceramics to see how they weather the space environment. NASA

Much of what is known about outer space’s ravaging character has come from the Long Duration Exposure Facility (LDEF). Launched in 1984 by the space shuttle Challenger, LDEF was mounted with a variety of metals, polymers, and ceramics to see how they weather the space environment. The satellite completed more than 32,000 Earth orbits at altitudes ranging from 275 to 175 miles before the shuttle Columbia returned it to Earth in 1990.

The LDEF results confounded many researchers. Some material samples that experts thought would survive turned out to quickly erode, while others that were expected to deteriorate managed to endure the many assaults from space.

"It tells us that we do not yet have a really good predictive understanding of the underlying chemistry that determines how many of these materials age in space," said new project leader Steven Sibener, a professor of chemistry and director of the Materials Research Science and Engineering Center at the University of Chicago.

This LDEF sample shows weathering. NASA

"The current materials used in space are still what I would call first-generation space materials that just happen to work at some level. We intend to go beyond such fortuitous situations and actually develop improved new materials using molecular-level understanding of the relevant chemistry to achieve intentionally designed performance advantages. Recent advances in materials experimentation, chemical synthesis, and theory make this the right time to tackle this challenging problem, said Sibener.

The new institute in Chicago will be called The Center for Materials Chemistry in the Space Environment, and will open its doors for business on May 1, 2002. Though it will be based at the University of Chicago, the center will involve collaborations with scientists and engineers from institutions all over the United States.

Back to MURI Home Page