Observational Bias and the Clustering of Distant Eccentric Kuiper Belt Objects
Observational Bias and the Clustering of Distant Eccentric Kuiper Belt Objects
复制标题
观测偏差和遥远偏心柯伊伯带天体的聚类
DOI：
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
M. Brown
中科院分区：
文献类型：
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作者：
M. Brown
假设一颗巨大的行星九存在于外太阳系的一个遥远的偏心轨道上，这是受到观测的启发，这些观测表明柯伊伯带中最遥远的偏心轨道的物体具有物理对齐的轨道，也就是说，它们聚集在近日点的经度上，并且具有相似的轨道平面。然而，关于观测偏差对这些观测的影响，特别是对近日点的影响，仍然存在问题。具体来说，遥远的偏心柯伊伯带天体（KBO）往往是暗淡的，只有在它们的近日点附近才能观察到，这表明已知遥远天体的近日点可能会受到天空中有限的深度测量位置的强烈偏见。我们已经开发了一种方法来严格估计柯伊伯带观测的近日点经度偏差。我们发现，10个已知的KBO的半长轴超过230 Au的概率是1.2%，来自一个人口与统一的近日点经度。结合观察到的这些物体的轨道极点也聚集在一起，在随机分布的样本中检测到这两个独立集群的总概率为0.025%。虽然观测偏差在这些观测中明显存在，但它不太可能解释观测到的遥远偏心KBO的排列。
The hypothesis that a massive Planet Nine exists in the outer solar system on a distant eccentric orbit was inspired by observations showing that the objects with the most distant eccentric orbits in the Kuiper Belt have orbits that are physically aligned, that is, they are clustered in longitude of perihelion and have similar orbital planes. Questions have remained, however, about the effects of observational bias on these observations, particularly on the longitudes of perihelion. Specifically, distant eccentric Kuiper Belt objects (KBOs) tend to be faint and only observable near their perihelia, suggesting that the longitudes of perihelion of the known distant objects could be strongly biased by the limited number of locations in the sky where deep surveys have been carried out. We have developed a method to rigorously estimate the bias in longitude of perihelion for Kuiper Belt observations. We find that the probability that the 10 known KBOs with semimajor axis beyond 230 au are drawn from a population with uniform longitude of perihelion is 1.2%. Combined with the observation that the orbital poles of these objects are also clustered, the overall probability of detecting these two independent clusterings in a randomly distributed sample is 0.025%. While observational bias is clearly present in these observations, it is unlikely to explain the observed alignment of the distant eccentric KBOs.
DOI：
10.3847/1538-3881/aa6db5
发表时间：
2017
期刊：
The Astronomical Journal
影响因子：
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作者：
Bannister M
通讯作者：
Bannister M