Economical Photochemistry at 100,000 Feet

As part of an undergraduate environmental chemistry class, students are given a project with budget constraints that utilizes a high altitude weather balloon for ultraviolet and vacuum ultraviolet photochemistry. The student project encompassed two flights and retrievals. Each flight climbed to over 100,000 feet above sea level carrying a payload of electronics and photochemical experiments. Students used Global Positioning units to track the flight, a digital camera to record images, an electronic thermometer to record the temperature and two methods to hold the chemicals in place while interacting with intense solar radiation. At the peak altitudes, there are more intense radiation fluxes of ultraviolet (UV) and vacuum ultraviolet (VUV) radiation as well as significant differences in pressure and temperature compared to the surface. The experiments cost approximately $500 (balloon, camera, GPS, etc) and carried a 1.5 kg payload. Once the payload is retrieved, Scanning Electron Microscopy, Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF-MS) and Fourier Transform-Infrared Spectroscopy (FT-IR) are used to analyze samples. A side project with a middle school science class involved loading Madagascar hissing cockroaches on both flights, showing young students science can be open ended and adventurous.