A systematic 1 to 5 micron infrared spectral survey of icy, airless, outer solar system satellites of Saturn and Uranus will be conducted by Dr. William Grundy, to take advantage of dramatic improvements in the state of the art of astronomical infrared spectrometers. Many of these satellites have yet to be well-observed with sensitive modern instruments so tremendous gains can be made relative to previous observations, and the potential for discovering new minority species on their surfaces is high, as exemplified by Dr. Grundy's recent discovery of CO2 ice on Ariel.
Interest in minority species on icy satellites has expanded rapidly, fueled by recent discoveries of many new species (mostly on Jovian satellites, so far) and a growing understanding of the connections between minority species and chemical and physical evolution driven by processes such as radiolysis, photolysis, and volatile transport. Infrared spectroscopy is the best tool for detecting new compounds and for learning about their phase states, temperatures, etc. New discoveries made through this project offer rich opportunities for attracting broader scientific and public interest (see below). In addition to providing a much more detailed view of chemistry of icy satellites surfaces, the new data will enable us to investigate the spatial distributions and physical/thermal states of newly discovered minority species, shedding considerable light on their origins and eventual fates. This type of work can only be done at moderately high spectral resolution. The instruments to be used offer five to ten times higher spectral resolution than the Cassini spacecraft VIMS instrument, so the data produced by this project will be complementary to Cassini's much higher spatial resolution.
The excellent potential for discovering new species offered by this project translates into significant impact beyond of the study of icy satellites and the processes acting on their surfaces. These discoveries can also provide valuable information about the evolution of astrobiologically important chemicals and the distribution of potentially exploitable resources in the outer solar system. Some of these materials may have contributed to the surface/atmospheric environments of early Earth and Mars, via meteorite delivery, and may even have played a key role in the origin of life. The discoveries awaiting this project will also be of considerable interest to the public. Since they are easily understood and communicated by the media, the likelihood of newly discovered compounds being widely reported is high. The broad attention that can be attracted by such discoveries helps maintain citizen interest in publicly-funded science. Dr. Grundy is also involved in educational efforts which leverage the excitement of ongoing scientific research such as this. These activities include working with Navajo and Hopi middle school science teachers and their classes. Both Navajo and Hopi communities are underrepresented in science, mathematics, engineering, and technology. Undergraduate summer students are involved in the research through NSF's Research Experiences for Undergraduates program. ***
