We analyze images of a rock on Ryugu acquired in situ by MASCam, the camera on the mascot lander, with the aim of identifying possible carbonaceous chondrite (CC) analogs. The rock’s reflectance ( at phase angle ) is consistent with Ryugu’s average reflectance, suggesting that the rock is typical for this asteroid. A spectrophotometric analysis of the rock’s inclusions provides clues to its CC group membership. Inclusions are generally brighter than the matrix. The dominant variation in their color is a change in the visible spectral slope, with many inclusions being either red or blue. Spectral variation in the red channel hints at the presence of the 0.7μm absorption band linked to hydrated phyllosilicates. The inclusions are unusually large for a CC; we find that their size distribution may best match that of the Renazzo (CR2) and Leoville (CV3) meteorites. The Ryugu rock does not easily fit into any of the CC groups, consistent with the idea that typical Ryugu-type meteorites are too fragile to survive atmospheric entry.

我们分析上Ryugu岩石的图像原位获取由MASCam，在相机吉祥物着陆器，以确定可能的碳质球粒（CC）的类似物的目的。岩石的反射率（在相位角）是具有Ryugu的平均反射率相一致，这表明岩是典型的这种小行星。岩石的夹杂物的分光光度分析提供线索的CC组成员。夹杂物一般比基质亮。在它们的颜色主导变化是在可见光谱的斜率的变化，与许多包含物是红色或蓝色。在0.7的存在下，在红色通道提示频谱变化μ米吸收带链接到页硅酸盐水合。夹杂物是一个CC非常大; 我们发现，他们的大小分布最匹配的Renazzo（CR2）和Leoville（CV3）的陨石。该Ryugu岩石不容易融入任何CC组，想法，典型Ryugu型陨石太脆弱生存进入大气层一致的。