The Japanese Hayabusa2 spacecraft returned samples from the asteroid Ryugu in December 2020, and several results on the properties of the particles have been published since. A detailed geochemical analysis determined that the total organic carbon abundance of the sample was on average 2.92 wt%. This value is much less than the 14.6–59.3 vol% estimated from remote-sensing data for Ryugu coupled with the albedos of irradiated meteorites and organic matter. Understanding the reasons for this discrepancy is paramount to accurately predict the composition of C-complex asteroids. Here we explore several factors that may affect the estimates of organic matter abundance made using remote-sensing data. Such factors include the distribution of organic matter, the porosity and roughness of the surfaces of asteroids, and inconsistencies between the observation geometries used by remote-sensing and laboratory investigations. We posit that discussing such factors may fuel further experimental investigations of the effects of irradiation on asteroid surfaces and, thus, improve predictions of their organic composition.

日本隼鸟二号航天器于 2020 年 12 月从小行星龙宫带回了样本，此后发布了有关粒子特性的几项结果。详细的地球化学分析确定样品的总有机碳丰度平均为 2.92 wt%。该值远低于根据龙宫遥感数据以及受辐射陨石和有机物的反照率估计的 14.6–59.3 vol%。了解这种差异的原因对于准确预测 C 复合小行星的成分至关重要。在这里，我们探讨了可能影响使用遥感数据进行有机物丰度估计的几个因素。这些因素包括有机物的分布、小行星表面的孔隙度和粗糙度，以及遥感和实验室研究使用的观测几何形状之间的不一致。我们认为，讨论这些因素可能会促进对小行星表面辐照影响的进一步实验研究，从而改善对其有机成分的预测。