From expanding marshmallow Peeps and music-modulated light-emitting diodes to clean water technology, exhibits representing a cross-section of Cornell's physical sciences and engineering expertise will be part of a Washington, D.C., festival aimed at promoting the sciences.

The first annual USA Science and Engineering Festival takes place in the nation's capital Oct. 10-24, with a two-day Expo on the National Mall Oct. 23-24. Cornell is an official partner of the festival, and the Office of the Vice Provost for Research is sending two exhibitors to the event. Cornell will be among 1,500 exhibitors from more than 500 institutions at the Expo, aimed at demonstrating scientific concepts to a general audience.

One of the Cornell exhibits, sponsored by the Center for Nanoscale Systems Institute for Physics Teachers (CIPT), converts light to music, sends it through the air or down an optical fiber, and converts it back to music. This exhibit is a new larger-scale demonstration version of a high school physics lab made available to physics teachers across the country by CIPT. Three different songs are simultaneously sent down a single optical fiber via three different colored LEDs. Color filters are then used to sort out which signals get to the speaker and which are blocked.

Another exhibit, hosted by the Cornell Laboratory for Accelerator-based Sciences and Education (CLASSE), will teach the public about the physical effects on materials placed inside a vacuum chamber where the air pressure is much less inside than outside the chamber. Using a vacuum pump and a bell jar, exhibitors will give demonstrations of what happens to such objects as balloons, marshmallow Peeps and water when placed in a vacuum and air is evacuated. The activity has been conducted by CLASSE staff at a number of after-school enrichment programs throughout central New York.

The CLASSE and CIPT exhibits will be located in the space reserved for the National Science Foundation, which provides funding for both organizations.

Cornell will further be represented by AguaClara, a student engineering group that designs low-cost, electricity-free water treatment plants for rural communities in Honduras. Other Cornell-affiliated exhibits will include one hosted by the National Nanotechnology Infrastructure Network, and two NASA exhibits on the Mars rovers and SOFIA.

Festival organizers expect thousands of participants to attend the two-week event, billed as a "multicultural, multigenerational and multidisciplinary celebration of science in the United States." For more information: http://www.usasciencefestival.org/.