Allain’s nanomaterials study may lead to understanding asteroid, moon origins
Prof. J.P. Allain’s expertise in examining radiation effects on the surfaces of nanomaterials may help unlock mysteries of the origins of huge heavenly bodies, such as asteroids and moons.
Allain’s RSSEL (Radiation Surface Science and Engineering Laboratory) group in Nuclear, Plasma, and Radiological Engineering at Illinois has joined a $5.5 million National Aeronautics and Space Administration funded project led by the Arizona-based Planetary Science Institute. NASA has chosen the Arizona institute as a node for the Solar System Exploration Research Virtual Institute (SSERVI), established to advance basic and applied research for lunar and planetary science, and advance human exploration of our solar system.
The Planetary Science Institute’s Toolbox for Research and Exploration (TREX) project will develop tools and research methods to prepare for human exploration of the Moon, near-Earth asteroids, and the Martian moons Phobos and Deimos. Fine dust that covers these celestial bodies’ surfaces makes analysis challenging, particularly as radiation strikes the surfaces and causes reactions that change the dust particles’ surface chemistry.
That is where Allain’s group comes in. The group examines fundamental particle-driven synthesis while diagnosing a material’s surface structure and composition using the custom-designed IGNIS facility. IGNIS can expose surfaces to a collection of energetic particles under high-pressure and high-temperature environmental conditions and characterize them in-situ by using x-ray photoelectron spectroscopy, ion-scattering spectroscopy, and Raman spectroscopy in a single chamber. The facility is also currently being upgraded to add microscopy to its suite of surface technology. IGNIS is a facility that was custom-made and completely designed by Allain’s NPRE students in his first two years at Illinois.
Allain and his students corroborate their findings with multi-scale predictive computational codes developed by Allain’s computational irradiation materials science sub-group, who work closely with the experimental group.
An invited talk Allain gave about IGNIS and in-situ characterization in 2015 at the XXIX International Conference on Photonic, Electronic and Atomic Collisions in Toledo, Spain, and the subject of a recent invited Topical Review paper in the Journal of Physics (Applied Physics D July 2017 issue) struck a chord with his collaborator Daniel Savin, a Columbia University astrophysicist. Realizing how useful IGNIS would be for the TREX project, Savin encouraged Allain to join the investigation.
“What’s exciting is that our group, with world expertise in looking at surface chemistry and physics with materials interacting with radiation, has been looking at surfaces of nanoparticles, and now we get to look at surfaces of planets!” Allain enthused. “More specifically we are examining surfaces of fine-grained bodies from asteroids and surrogate materials under simulated radiation exposure conditions created in our IGNIS facility to decipher space weathering effects. We are uncovering how the space environment changes the surfaces of these airless bodies so that we can understand the spectral information inferred from their reflectance.”
With NPRE graduate student Camilo Jaramillo, Allain will examine lunar samples collected during the U.S. Apollo missions and surrogate minerals such as olivine, as well as samples from an asteroid mission the Japanese conducted in 2007 of the near-earth asteroid Itokawa.
“This project will be the first time scientists have looked at the surface chemistry of micro-scale loose dust particles during low-energy irradiation; no one has done that before,” Allain said. “This is a first for me; it’s a very different area for using our knowledge and know-how. We’re exploring how radiation impacts the surfaces (of the moons and asteroids), and that chemistry will tell us a lot about their origins.”
Allain expects the project will expand his group’s research and overall NPRE department into a variety of new areas. “The work with the Institute has opened so many doors,” he said. “The data that we’re getting is so unique, a lot of people are engaging with us about the capability of our facility.”