论文标题
通过表征小行星2020 CD $ _3 $来建立地球的微型季节
Establishing Earth's Minimoon Population through Characterization of Asteroid 2020 CD$_3$
论文作者
论文摘要
我们报告了我们对地球第二个已知的临时天然卫星或微小小行星2020 CD3的详细表征。可以根据其面积比和宽带光度法来排除人工来源，这表明它是小行星分类学中属于S或V复合物的硅酸盐小行星。 2020年CD3的发现首次可以比较其预期的物理和动态特性的已知最小值模型与理论模型之间的比较。估计的直径为1.2+0.4-0.2 m，在第一个已知的minimoon（2006 RH120）大约十年后，地理为中心捕获与理论预测一致。与模拟平均值相比，2020年CD3的捕获持续时间至少长2.7年，但它与具有接近月球接触的模拟微型仪一致，从而为轨道模型提供了更多支持。 2020年CD3的非典型旋转周期比理论上的预测更长，这表明我们对仪表小行星的理解需要修订。即将推出的Vera C. Rubin天文台遗产对时空和时间的调查，可以预期更多的发现和人口的详细表征。
We report on our detailed characterization of Earth's second known temporary natural satellite, or minimoon, asteroid 2020 CD3. An artificial origin can be ruled out based on its area-to-mass ratio and broadband photometry, which suggest that it is a silicate asteroid belonging to the S or V complex in asteroid taxonomy. The discovery of 2020 CD3 allows for the first time a comparison between known minimoons and theoretical models of their expected physical and dynamical properties. The estimated diameter of 1.2+0.4-0.2 m and geocentric capture approximately a decade after the first known minimoon, 2006 RH120, are in agreement with theoretical predictions. The capture duration of 2020 CD3 of at least 2.7 yr is unexpectedly long compared to the simulation average, but it is in agreement with simulated minimoons that have close lunar encounters, providing additional support for the orbital models. 2020 CD3's atypical rotation period, significantly longer than theoretical predictions, suggests that our understanding of meter-scale asteroids needs revision. More discoveries and a detailed characterization of the population can be expected with the forthcoming Vera C. Rubin Observatory Legacy Survey of Space and Time.
