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一个红色且极其长长的星际小行星的短暂访问
Karen J Meech1, Robert Weryk1, Marco Micheli2,3
1Institute for Astronomy, 2680 Woodlawn Drive, Honolulu, Hawaii 96822, USA.
Nature
|November 22, 2017
概括
首次发现的星际物体,
科学领域:
- 天文学与天体物理学
- 星球科学
背景情况:
- 太阳系形成模型预测行星体被射入星际空间.
- 之前的搜索没有检测到星际物体,
- 没有比较太阳系材料与其他行星系统的方法.
研究的目的:
- 确认1I/2017 U1 ('Oumuamua') 的太阳系外起源.
- 能够对来自不同行星系统的物质进行比较分析.
- 评估星际物体的数量和特征.
主要方法:
- 分析轨迹以确定太阳系外的起源.
- 表面组成的光谱测量.
- 光曲线观测以确定形状和尺寸.
主要成果:
- 确认Oumuamua的轨道是太阳系外的.
- 没有彗星活动.
- 表面呈光谱红色,形状极为长方形 (长宽比为10:1),估计半径为102米.
- 在已知的太阳系天体中, 物体的尺寸是前所未有的.
结论:
- 发现Oumuamua证实了星际物体的存在.
- 以前对星际物体数量密度的估计可能被低估了.
- 提供了一个独特的机会来研究来自其他行星系统的材料.
- 未来使用更强大的仪器进行调查, 可能会发现更多的星际物体.
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