Fig. 2: Sample swath indicating the effective abundances of pristine (unaltered) carboxylic acids within the top 100 micrometers and at depths >100 micrometers for various points on Enceladus moving along a path heading 25° west of north starting from the end of the Baghdad fracture at 70°S.
From: Low effective ultraviolet exposure ages for organics at the surface of Enceladus
Abundances assume the range of glycine decarboxylation half-lives at 9.5 AU of between 2 and 9.4 years, bounded by the measurements of Guan et al. (2010)30 and Johnson et al. (2012)15 (Table 1). The half-lives here are reduced to reflect lower average solar illumination with changing solar incidence angles away from the equator. Plume grain deposition rates (left y-axis) are from eight-point sources and slope of the power-law size distribution α = 3.17, with the time (years) to build up to a depth of 100 micrometers indicated on the right y-axis.
