Evidence for a source of H chondrites in the outer main asteroid belt
Evidence for a source of H chondrites in the outer main asteroid belt
复制标题
外主小行星带 H 球粒陨石来源的证据
DOI：
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发表时间：
2014
期刊：
影响因子：
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通讯作者：
D. Pricopi
中科院分区：
文献类型：
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作者：
D. Nedelcu;M. Birlan;M. Popescu;O. Bădescu;D. Pricopi
目标。在本文中，我们报告的近红外光谱观测的最大的潜在危险的小行星之一，（214869）2007 PA8。在对这一物体进行矿物学分析之后，根据长期数值积分，调查了其可能源区的动态输送机制。方法.利用1 μ m和2μm谱带的位置，通过与RELAB陨石谱的曲线匹配，分析了（214869）2007 PA8的光谱。通过对1275个克隆体追踪到源区20万年的数值积分，研究了其动力学演化。结果（214869）2007 PA8有一个非常年轻的表面，其组成更类似于陨石，而不是任何其他类型的普通球粒陨石。它来自近地空间的外主带，通过离心泵与木星产生5：2的平均运动共振。在远离（6）Hebe的地方发现了它的源区，提出了存在第二个具有完全不同的吸积后历史的Hebe母体的可能性。未来在5：2共振区的光谱测量将很可能发现其他具有H球粒陨石成分的小行星。
Aims. In this paper we report near-infrared spectroscopic observations of one of the largest potentially hazardous asteroids, (214869) 2007 PA8. Mineralogical analysis of this object was followed by the investigation of the dynamical delivery mechanism from its probable source region, based on long-term numerical integrations. Methods. The spectrum of (214869) 2007 PA8 was analysed using the positions of 1 μ ma nd 2μm bands and by curve-matching with RELAB meteorites spectra. Its dynamical evolution was investigated by means of a 200 000-year numerical integration in the past of 1275 clones followed to the source region. Results. (214869) 2007 PA8 has a very young surface with a composition more akin to H chondrites than to any other type of ordinary chondrite. It arrived from the outer Main Belt in the near-Earth space via the 5:2 mean motion resonance with Jupiter by eccentricity pumping. Identification of its source region far from (6) Hebe raises the possibility of the existence of a second parent body of the H chondrites that has a radically different post-accretion history. Future spectroscopic surveys in the 5:2 resonance region will most likely discover other asteroids with an H chondrite composition.
一组近地和穿越火星小行星的表面组成和分类
影响因子：
3.2
作者：
Sanchez;Juan A;Michelsen;Vishnu;Nathues;Andreas
通讯作者：
Andreas