A Tale of Two Comets - The FORCAST Story

The properties of small, primitive bodies in the solar system, including individual comets and comet-families, whose origins lie beyond the water frost line (> 5 AU) provide critical insight into the formation of Solar System solids and establishes observational constraints for planetary system formation invoking migration. We propose to obtain 4.9 to 37.1 micron spectra and four-filter imagery of two Oort Cloud comets, C/2013 US10 (Catalina) and C/2013 X1 (Pan-STARRS), with FORCAST to determine the composition of the coma materials. Cometary dust contains remnants of both primordial material in the comet-formation zone as well as processed material transported from hotter regions closer to the Sun. We will address two questions: Q1. What information do cometary grains provide us concerning the evolution of the early solar system? Q2. What are the fundamental differences between comets originating from different regions and epochs during solar system formation? Comets form our most direct link to the earliest stages of the formation and evolution of the solar system. The narrative tale, gleaned through the study of grains, ices, and volatiles, is an account of our origins.