Sources and Orbital Evolution of Interplanetary Dust Accreted by Earth
Sources and Orbital Evolution of Interplanetary Dust Accreted by Earth
复制标题
地球吸积的行星际尘埃的来源和轨道演化
DOI：
10.1007/978-1-4419-8694-8_2
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发表时间：
2001
影响因子：
5
通讯作者：
K. Grogan
中科院分区：
文献类型：
--
作者：
S. Kortenkamp;S. Dermott;D. Fogle;K. Grogan
我们回顾了观测和理论上的限制小行星和彗星的相对贡献行星际尘埃粒子（IDP）的黄道光云。估计的贡献范围很广，但最丰富的明确来源是小行星家族，观测到的黄道尘埃带的祖先。黄道光云的其他特征表明，非家族小行星和短周期彗星也有贡献。从所有这些来源的IDPs的轨道演变的数值模拟揭示了自然机制，偏置地球尘埃吸积率大大有利于小行星IDPs，特别是那些起源于Eos，Themis和Koronis小行星家族。在较长的时间尺度上，所有小行星来源的内流离失所者的吸积率应相差2至3倍，并显示出与地球轨道偏心率反相关的100 kyr周期。深海沉积物中的地外3He浓度具有类似的周期性，但与预测的变化相差50 kyr。文中还讨论了这种180°相位滞后的可能解释。
We review observational and theoretical constraints on the relative contributions of asteroids and comets to interplanetary dust particles (IDPs) in the zodiacal cloud. The estimated contributions span a broad range but the most abundant unambiguous sources are asteroid families, the progenitors of the observed zodiacal dust bands. Other features of the zodiacal cloud indicate additional contributions from non-family asteroids and short-period comets. Numerical modeling of the orbital evolution of IDPs from all these sources reveals natural mechanisms which bias the terrestrial dust accretion rate heavily in favor of asteroidal IDPs, in particular, those originating in the Eos, Themis, and Koronis asteroid families. Over an extended time scale the accretion rate of IDPs from all asteroidal sources should vary by a factor of two to three and display a 100 kyr periodicity that is anti-correlated with Earth’s orbital eccentricity. Extraterrestrial 3He concentrations in deep-sea sediments have a similar periodicity but are 50 kyr out of phase with the predicted variations. Possible expla- nations of this 180° phase lag are discussed.