Quantitative Aspects of Space Weathering: Implications for Regolith Breccia Meteorites and Asteroids
Quantitative Aspects of Space Weathering: Implications for Regolith Breccia Meteorites and Asteroids
复制标题
空间风化的定量方面：对风化角砾陨石和小行星的影响
DOI：
10.1038/nature02578
复制
发表时间：
2004
期刊：
影响因子：
64.8
通讯作者：
L. Keller
中科院分区：
文献类型：
--
作者：
S. Noble;C. Pieters;L. Keller
空间风化是指暴露于空间环境中的材料所发生的物理和光学变化。通过对月球土壤的研究，人们对这些变化越来越了解。然而，空间风化的影响取决于主体材料所暴露的物理环境，因此，影响可能会因物体而异。空间风化的光学效应是由微陨石撞击和太阳风溅射产生的纳米铁（npFe（sup 0））引起的。在小行星带中，天体距离太阳比月球更远，并且众所周知，太阳风注入和溅射较少。撞击速度较小，导致熔化和蒸发较少，因此空间风化产物较少。小行星带的撞击率更高，这将导致更多的粉碎，进一步稀释任何风化产物。因此，小行星风化层应该比月球土壤含有更少的空间风化产物。然而，即使是非常小程度的空间风化也会对土壤的光学特性产生巨大的影响。讨论了空间风化的光学效应。
Space weathering is defined as the physical and optical changes incurred by material exposed to the space environment. Through studies of lunar soils, these changes are becoming well understood. However, the effects of space weathering are dependent on the physical environment to which the host materials are exposed, and thus, the effects will likely vary from body to body. The optical effects of space weathering result from nanophase iron (npFe(sup 0)) created during micrometeorite bombardment and solar wind sputtering. In the asteroid belt, bodies are farther from the sun than our Moon, and are widely known to incur less solar wind implantation and sputtering. The velocity of impacts is smaller resulting in less melting and vaporization, and therefore fewer space weathering products. The impact rate in the asteroid belt is greater, which will result in more comminution, further diluting any weathering products. Ergo, asteroidal regoliths should contain fewer space weathering products than lunar soils. However, even very small degrees of space weathering can have dramatic consequences for the optical properties of soils. A discussion on the optical effects of space weathering is presented.