Comparison of UCAMM infrared measurements for carbonyl, aromatic carbon, and hydrogen bonded to carbon, displayed with the corresponding infrared features in meteorite (Orthous-Daunay et al. 2013; Quirico et al. 2014; Kebukawa et al. 2011, separating the first three infrared subclasses defined in the Kebukawa spectral analysis) and IDP (Matrajt et al. 2005b) insoluble organic matter. Left: carbonyl-to-aromatic-carbon ratio as a function of the CH to C=C areas; right: integrated optical depth area of the CH versus C=C bands as a function of H/C ion probe (NanoSIMS) independent measurements. The UCAMMs without available H/C measurements are set at a zero H/C value. Labels correspond to meteorite groups, as reported in these articles