Model predictions for the 2001 Leonids and implications for Earth‐orbiting satellites
Model predictions for the 2001 Leonids and implications for Earth‐orbiting satellites
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2001 年狮子座流星雨的模型预测及其对地球轨道卫星的影响
DOI：
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发表时间：
2001
期刊：
影响因子：
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通讯作者：
B. Cooke
中科院分区：
文献类型：
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作者：
P. Brown;B. Cooke
一个数值模型的狮子座流的开发，早期的模型已被应用到英仙座流的基础上。该模型的结果适用于2001年狮子座返回。通过研究狮子座母彗星55 P/Tempel-Tuttle释放的单个“细流”的全三维分散，我们得出了每个轨迹空间密度随时间变化的估计。利用这一结果沿着的估计中心的位置为个人的小溪和适合以前的狮子座流星雨的风暴配置文件，我们估计，从阵雨的活动将是广泛的，相对较强（天顶每小时率可能超过1000）。特别是，从1766年和1799年喷射的细流有助于活动峰值附近10和12 UT 2001年11月18日，分别。1633年、1666年和1699年的其他更老的物质，以及1866年和1833年的更近的喷射，促成了11月18日在17.5 UT附近的更广泛的次极大。与其他已发表的预测2001年狮子座流星雨活动的模型相比，在时间上基本一致，但在活动的相对大小上，模型有很大的不同（其他模型认为会更大）。对地球静止带内的卫星而言，撞击危险存在着显著的各向异性，而位于西半球上空的卫星最有可能受到影响。2001年狮子座流星雨回归的综合通量表明，其危害程度比1999年狮子座流星雨风暴大一个量级。
A numerical model of the Leonid stream is developed, based on an earlier model which has been applied to the Perseid stream. The results for this model are applied to the 2001 Leonid return. By examining the full three-dimensional dispersion of individual ‘streamlets’ released from the Leonid parent comet, 55P/Tempel–Tuttle, we have derived an estimate for the temporal change in spatial density of each trail. Using this result along with an estimate for the location of the centres for individual streamlets and fits to previous Leonid storm profiles, we estimate that the activity from the shower will be broad and relatively strong (zenithal hourly rates perhaps in excess of 1000). In particular, streamlets from the 1766 and 1799 ejections contribute to activity peaking near 10 and 12 ut on 2001 November 18, respectively. Additional older material from 1633, 1666 and 1699, as well as more recent ejections from 1866 and 1833, contributes to a much broader secondary maximum near 17.5 ut on November 18. Comparison with other published models of predicted Leonid activity in 2001 shows general agreement in terms of timing, but the models differ significantly in terms of the relative magnitude of the activity (which other models suggest will be larger). Significant anisotropy in the impact hazard exists for satellites in the geostationary belt, with those over western longitudes most likely to be affected. Integrated fluences for the 2001 Leonid return suggest a hazard of order one magnitude greater than occurred for the 1999 Leonid storm.