论文标题
（25143）Itokawa的太空风化时间尺度的估计：对其复兴过程的影响
Estimation of space weathering timescale on (25143) Itokawa: Implications on its rejuvenation process
论文作者
论文摘要
语境。已经通过多种方法（即实验，样本分析和理论方法）研究了近地S型小行星的空间风化时间尺度，但存在数量级的差异。目标。我们的目的是使用hayabusa-amica图像检查近地s型小行星，itokawa上的空间风化时间尺度，并进一步研究小行星的进化过程。方法。我们专注于通过与星际尘埃颗粒（IDP）的撞击产生的巨石表面上的明亮斑点。我们将明亮的斑点尺寸分布与IDP通量模型进行了比较，以确定空间风化时间尺度。结果。结果，我们发现Itokawa巨石表面上的空间风化时间尺度为10 $^3 $年（范围为10 $^2 $ -10 $^4 $年），这与太阳能风中的Light Ions的太空风化时间一致。结论。从这个结果中，我们得出结论，Itokawa的表面在10 $^3 $年中很快被风化，但是部分表面是通过近期产生Kamoi火山口的攻击而暴露的。
Context. The space weathering timescale of near-Earth S-type asteroids has been investigated by several approaches (i.e., experiments, sample analyses, and theoretical approaches), yet there are orders of magnitude differences. Aims. We aim to examine the space weathering timescale on a near-Earth S-type asteroid, Itokawa using Hayabusa-AMICA images and further investigate the evolutional process of the asteroid. Methods. We focused on bright mottles on the boulder surfaces generated via impacts with interplanetary dust particles (IDPs). We compared the bright mottle size distribution with an IDP flux model to determine the space weathering timescale. Results. As a result, we found that the space weathering timescale on Itokawa's boulder surfaces is 10$^3$ years (in the range of 10$^2$-10$^4$ years), which is consistent with the timescale of space weathering by light ions from the solar wind. Conclusions. From this result, we conclude that Itokawa's surface has been weathered shortly in 10$^3$ years but portions of the surface are exposed via seismic shaking triggered by a recent impact that created the Kamoi crater.
