The University of Tennessee, Knoxville


Outstanding Researcher Dr. Larry Townsend

Dr. Larry Townsend, professor in nuclear engineeringDr. Larry Townsend, professor in nuclear engineering, is shooting for the moon -- literally. In addition to his various other research efforts, Townsend is applying his work in space radiation protection and transport codes to NASA's Cosmic Ray Telescope for the Effects of Radiation (CRaTER) project team, part of the Lunar Reconnaissance Orbiter (LRO) spacecraft. The spacecraft's 12-month mission will launch in December 2008.

CRaTER is one of six projects under development for LRO, which is the first of several planned robotic lunar missions to prepare for the return of humans to the moon. Collaborators for CRaTER include Boston University, Massachusetts Institute of Technology, UT, Aerospace Corporation and the Air Force Research Laboratory. Townsend, who is Measurements Team Leader of CRaTER, will investigate the effects of galactic cosmic rays on tissue-equivalent plastics experienced in a flight to the moon—more simply put, the effects of space radiation.

"I'm responsible for computational modeling of calibration runs and the radiation exposures expected during the actual mission. When the data are received from the mission, it will be partly my responsibility to analyze and interpret those data," said Townsend. "The project is going well. CRaTER's objectives include measuring and characterizing the radiation environment in the vicinity of the moon. The detectors we'll place on the spacecraft will be flying in polar orbits about 30 kilometers above the lunar surface."

Townsend is currently completing calculations modeling calibration runs to prepare for detector testing.

"We have to submit our concept design review to NASA," explained Townsend. Micron Technology Inc. is producing the silicon chips for the detector, which will be built by MIT and the Aerospace Corporation.

Townsend became involved in space radiation research while working for NASA Langley Research Center. "I helped develop space radiation transport codes and interaction models. I've been conducting this type of research for about 25 years now," said Townsend. His codes examine how the radiation fields of these particles are altered as they pass through matter.

"This research is actually part of a consortium of institutions. UT is the lead with approximately $2 million in funding. NASA internally spends another $1 million. The University of Houston, Roanoke College, SID Inc. and Worcester Polytechnic Institute are also involved," said Townsend. "The project uses atomic and nuclear reaction models to describe how these particles change identities and other physical properties when interacting with spacecraft shielding and human tissue. Our goal is to devise methods of protection against radiation for humans and electronics while in space."

Townsend has also been involved in other research endeavors. With support from the Department of Energy and TVA, Townsend worked with NE professor Dr. Laurence Miller and NE research professor Dr. F. R. Mynatt to develop a method for mounting a Generation IV modular nuclear reactor on a barge for transportation from the Gulf of Mexico upstream to other locations on the Mississippi, Ohio and Tennessee River systems.

"We developed a computer model of the layout and component sizes of steam plant components, such as turbines, condensers and generators, for actually generating electricity and worked with TVA to explore potential uses and limitations associated with transportation of modular reactor systems," explained Townsend.

Despite the time constraints that come with multiple projects and research interests, Townsend continues to enjoy teaching. "Interacting with the students is very important to me in my teaching," said Townsend.

"I've taught nine or ten different courses in my time in the college, and I've helped develop or modify several courses. For example, we've made changes in the NE Fundamentals course in response to alumni feedback, bringing the Fortran computer language back to the curriculum in order to prepare graduates for the field."

Townsend finds the growth in the number of students in the nuclear engineering department exciting.

"I know our undergraduate enrollment has at least doubled. About four years ago we had 24 students. Now I have nearly 40 students in one of my classes. We have distance education graduate students, and the incoming classes just keep getting larger," he said.

For more information about CRaTER, please visit


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