共查询到2条相似文献,搜索用时 0 毫秒
1.
We present results obtained for Epinal (H5), an ordinary chondrite meteorite, irradiated with 60 keV Ar++ ions, simulating solar wind heavy particle irradiation. Bidirectional reflectance spectra (0.3-2.67 μm) measured after irradiating Epinal samples with different ion fluences exhibit a progressive reddening that is similar to the spread of spectra observed for S-type near-Earth asteroids. The timescales for inducing the same effects in space as those obtained in laboratory are estimated to be 104-106 yr. These results suggest irradiation by heavy ions may be a very efficient weathering process in near-Earth space. 相似文献
2.
Lunar X-ray fluorescence observations by the Chandrayaan-1 X-ray Spectrometer (C1XS): Results from the nearside southern highlands 总被引:1,自引:0,他引:1
S. Narendranath P.S. Athiray B.J. Kellett C.J. Howe M. Grande I.A. Crawford S. Lalita S.Z. Weider L.R. Nittler D. Rothery N. Bhandari M.A. Wieczorek the CXS team 《Icarus》2011,214(1):53-66
The Chandrayaan-1 X-ray Spectrometer (C1XS) flown on-board the first Indian lunar mission Chandrayaan-1, measured X-ray fluorescence spectra during several episodes of solar flares during its operational period of ∼9 months. The accompanying X-ray Solar Monitor (XSM) provided simultaneous spectra of solar X-rays incident on the Moon which are essential to derive elemental chemistry. In this paper, we present the surface abundances of Mg, Al, Si, Ca and Fe, derived from C1XS data for a highland region on the southern nearside of the Moon. Analysis techniques are described in detail including absolute X-ray line flux derivation and conversion into elemental abundance. The results are consistent with a composition rich in plagioclase with a slight mafic mineral enhancement and a Ca/Al ratio that is significantly lower than measured in lunar returned samples. We suggest various possible scenarios to explain the deviations. 相似文献