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arXiv 1809.03549astro-ph.EP
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可执行近地天体巡天任务:四年的photometry

The Mission Accessible Near-Earth Objects Survey: Four years of photometry

Audrey Thirouin, Nicholas A. Moskovitz, Richard P. Binzel, Eric J. Christensen, Francesca E. DeMeo, Michael J. Person, David Polishook, Cristina A. Thomas, Davi… 展开作者

Audrey Thirouin, Nicholas A. Moskovitz, Richard P. Binzel, Eric J. Christensen, Francesca E. DeMeo, Michael J. Person, David Polishook, Cristina A. Thomas, David Trilling, Mark C. Willman, Brian Burt, Mary L. Hinkle, Teznie Pugh

摘要:

在四年半的时间里,可观测近地天体巡天任务收集了228个近地天体光变曲线。我们报告了82个近地天体的旋转光变曲线,21个近地天体的振幅和周期限制,30个近地天体和10个不倒翁的光变曲线在图像信噪比和观测区长度内没有发现变化。我们发现了2个周期小于20秒的超快速旋转体; 2016 MA的潜在旋转周期为18.4秒,2017 QG $_{18}$的旋转周期为11.9秒,并估计了在我们的项目中未检测到的快速/超快速旋转体的比例,以及在我们的典型观测区块中未检测到的中/长周期近地天体的百分比。我们总结了合成近地天体的一个简单模型的研究结果,以便利用测得的光变曲线幅度分布来推断天体的形态分布。该模型表明,轴比均匀分布可以再现所观察到的样品。这表明球形近地天体(例如,Bennu)几乎相当于高度细长的物体的数量(例如,Itokawa),由于多普勒延迟雷达成像分析的形状模型,可以直接测试结果。最后,我们充分确定了2个近地天体的特征,它们是2013 YS $_{2}$和2014 FA $_{7}$,因为它们的自转周期适中,$Δv$较低。

英文摘要:

Over 4.5 years, the Mission Accessible Near-Earth Object Survey (MANOS) assembled 228 Near-Earth Object (NEO) lightcurves. We report rotational lightcurves for 82 NEOs, constraints on amplitudes and periods for 21 NEOs, lightcurves with no detected variability within the image signal to noise and length of our observing block for 30 NEOs, and 10 tumblers. We uncovered 2 ultra-rapid rotators with periods below 20s; 2016MA with a potential rotational periodicity of 18.4s, and 2017QG$_{18}$ rotating in 11.9s, and estimate the fraction of fast/ultra-rapid rotators undetected in our project plus the percentage of NEOs with a moderate/long periodicity undetectable during our typical observing blocks. We summarize the findings of a simple model of synthetic NEOs to infer the object morphologies distribution using the measured distribution of lightcurve amplitudes. This model suggests a uniform distribution of axis ratio can reproduce the observed sample. This suggests that the quantity of spherical NEOs (e.g., Bennu) is almost equivalent to the quantity of highly elongated objects (e.g., Itokawa), a result that can be directly tested thanks to shape models from Doppler delay radar imaging analysis. Finally, we fully characterized 2 NEOs as appropriate targets for a potential robotic/human mission: 2013YS$_{2}$ and 2014FA$_{7}$ due to their moderate spin periods and low $Δv$.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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