Solar photochemistry using the space shuttle

A continuing source of difficulty in cometary astrophysics is understanding the origin of C2, C3, NH and CO(+) species in comets. An experiment is proposed to investigate these problems by continuously releasing suspected parent gases from the space shuttle and using a dye laser to selectively excite fragments produced as a result of solar photochemical decomposition of the molecules. The backscattered fluorescence is gathered by a telescope, spectrally filtered, and measured as a function of time after the laser pulse.