The Saturnian system has been explored by four spacecraft: Pioneer 11, Voyager 1 and 2, and Cassini. Only the last three took images suitable for photogeologic analysis of the surfaces of Saturn's moons, and over the decades, several research groups have published data about the crater distributions on the Saturnian satellites. These groups have used those data to draw conclusions about the impactor populations and resurfacing histories of the moons, but no one has examined how well the different data agree between the researchers. We present independent mapping of the crater populations of Saturn's moons Mimas, Rhea, and Iapetus, and compare them with many published crater populations. We found that Mimas data are the most consistent between different researchers, and Rhea data are the least consistent. We attribute these differences to (a) data biases where there are fewer images upon which to map Mimantean craters but a large variety exist for Rhean, and (b) Rhea likely has different terrains with different impact crater populations which have not been generally recognized before. We also found that Iapetus' small craters appear to have a shallow branch, as others have found, and that shallow branch is not attributable to completeness limitations. Other bodies have shallow branches at small diameters, too, but they are not as shallow as Iapetus's, which suggests varying impacting populations as one moves closer to Saturn, in line with others' work on planetocentric impactors.

中文翻译：

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土星卫星土卫一、土卫五和土卫八的陨石坑群

土星系统已由四艘航天器探索：先锋 11 号、航海家 1 号和2 号以及卡西尼号。只有最后三张拍摄了适合对土星卫星表面进行摄影地质分析的图像，几十年来，几个研究小组发表了有关土星卫星上陨石坑分布的数据。这些小组利用这些数据得出了有关撞击者数量和卫星表面重生历史的结论，但没有人检查研究人员之间不同数据的一致性程度。我们提出了土星卫星土卫一、土卫五和土卫八的陨石坑群的独立测绘，并将它们与许多已发表的陨石坑群进行比较。我们发现土卫一的数据在不同研究人员之间是最一致的，而土卫五的数据是最不一致的。我们将这些差异归因于（a）数据偏差，其中用于绘制 Mimantean 陨石坑的图像较少，但瑞亚陨石坑的图像种类繁多，（b）瑞亚陨石坑可能具有不同的地形和不同的撞击坑群，而这些陨石坑之前并未被普遍认识到。 。我们还发现土卫八的小陨石坑似乎有一个浅分支，正如其他人所发现的那样，并且该浅分支并不归因于完整性限制。其他天体也有小直径的浅分支，但它们不像土卫八那么浅，这表明当一个天体靠近土星时，撞击的种群会有所不同，这与其他人对行星中心撞击天体的研究是一致的。