Impact Cratering Experiments in Microgravity Environment
Impact Cratering Experiments in Microgravity Environment
复制标题
微重力环境下的撞击坑实验
DOI：
10.1006/icar.1994.1004
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发表时间：
2005
期刊：
影响因子：
3.2
通讯作者：
A. Fujiwara
中科院分区：
文献类型：
--
作者：
Y. Takagi;S. Hasegawa;H. Yano;Seigo Yamamoto;S. Sugita;K. Teramoto;C. Honda;K. Kurosawa;T. Nakada;M. Abe;A. Fujiwara
简介：muse - c /隼鸟号任务发现，小行星（25143）Itokawa是一个碎石堆，部分表面被风化层或毫米至厘米大小的砾石层覆盖[1,2]。虽然数量有限，但隼鸟号在石川的风化层或砾石平原上发现了一些陨石坑。这些结果再次证实了对撞击坑现象的理解对于研究小天体表面过程的重要性。然而，由于技术上的困难，在微重力环境下的撞击实验很少。最近，Colwell[4]对航天飞机有效载荷上布满灰尘的表面进行了一些撞击实验。然而，撞击速度非常低（小于100厘米/秒）。标度律可用的数据只有Gault和Wedekind[5]图1中的数据。需要在微重力环境下进行撞击实验，以阐明小天体上的过程，并充分利用小行星探索所带来的财富。我们在微重力环境下用一个落点塔进行了撞击实验。MUSES-C/隼鸟号采样装置[2]的性能测试使用了相同的设备和实验装置。弹坑形成时间：跌落塔实验的弱点是微重力状态持续时间短。我们先检查了陨石坑形成的时间。所有微重力实验的视频图像显示，陨石坑的形成在0.1秒内结束，1g下的陨石坑形成时间与微重力环境下没有任何差异。这一结果证明，在这种情况下，设施的微重力持续时间为4.5秒，足以进行撞击实验。陨石坑的最终直径：结果清楚地表明，陨石坑的直径形成在微重力
Introduction: The MUSES-C/Hayabusa mission found that Asteroid (25143) Itokawa is a rubble pile and some parts of the surface are covered by regolith or mm to cm size gravel layer [1, 2]. Although the number is limited, some craters were found on the regolith or gravel plain of Itokawa by Hayabusa [3]. These results reconfirmed that the understanding of impact cratering phenomena is important for studies of surface processes on small bodies. However, impact cratering experiments in microgravity environments were rare due to technical difficulties. Recently Colwell [4] performed some impact experiments into a dust-covered surface in a space shuttle payload. However, the impact velocities were very low ( less than 100 cm/sec). Only data available to the scaling law are data in Fig. 1 of Gault and Wedekind [5]. Impact cratering experiments in the microgravity environment are desired to elucidate process on small bodies and to make the best use of the wealth by asteroid explorations. We performed impact cratering experiments in microgravity environments using a drop tower. The same facility and experimental devices were used in the performance tests of MUSES-C/Hayabusa sampling devices [2]. Crater Formation Time: The weakest point of drop tower experiments is the short duration time of microgravity condition. We checked the crater formation time first. All the video images of microgravity experiments showed that the crater formation ends within 0.1 sec. Any difference between the crater formation time in 1 G and microgravity environment is not observed. This result certified that the microgravity duration time of the facility, 4.5 sec, is enough long for impact cratering experiments in this case. Crater Final Diameter: The result clearly showed that the diameters of craters formed in the microgravity