Grad Students Receive NASA Fellowships
Montana State University (MSU) electrical engineering graduate students David Hoffman and Amin Nehrir have each received a $30,000 fellowship through NASA's Graduate Student Researchers Program, giving them the opportunity to work with some of NASA's top scientists in laser technology as interns at Langley Research Center in Hampton, Va., next year. At the university in Bozeman, Hoffman and Nehrir's work with lidar (light detection and ranging) involves sending a pulse of laser light into the sky and letting it bounce off the particles suspended in the air. By measuring the amount of light that bounces back, how that light is scattered and the time it takes to return, scientists can learn about the composition of the lower atmosphere. Hoffman built a two-color lidar to finish his master's thesis; now he is building an optical filter that will allow lidar systems to differentiate between those airborne particles and atmospheric molecules -- identifying and quantifying dust, pollen, pollution, etc. Nehrir is building a differential absorption lidar system that will detect the amount and distribution of water vapor in the atmosphere. Both students' work could one day help scientists study the climate and could help move MSU from the instrument-building phase into atmospheric research, said Kevin Repasky, an assistant professor in electrical and computer engineering who advises both students. "They're starting to build instruments that are up there with other instruments being built around the world," he said. NASA is particularly interested in the small, 2 x 4 x 4-ft lidar assemblies MSU is building. By comparison, some lidars are large enough to fill an entire 40-ft cargo container, Repasky said. Those instruments could be used to help understand how clouds form around different types of airborne particles, which affects the entire water cycle, from the types of clouds that form to the amount of precipitation expected from them.
- An acronym of light detection and ranging, describing systems that use a light beam in place of conventional microwave beams for atmospheric monitoring, tracking and detection functions. Ladar, an acronym of laser detection and ranging, uses laser light for detection of speed, altitude, direction and range; it is often called laser radar.
- Electromagnetic radiation detectable by the eye, ranging in wavelength from about 400 to 750 nm. In photonic applications light can be considered to cover the nonvisible portion of the spectrum which includes the ultraviolet and the infrared.
- The technology of generating and harnessing light and other forms of radiant energy whose quantum unit is the photon. The science includes light emission, transmission, deflection, amplification and detection by optical components and instruments, lasers and other light sources, fiber optics, electro-optical instrumentation, related hardware and electronics, and sophisticated systems. The range of applications of photonics extends from energy generation to detection to communications and...
MORE FROM PHOTONICS MEDIA