相关实验视频
Updated: Jul 9, 2026

11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
了解近地小行星的分布
1Center for Radiophysics and Space Research, Cornell University, Ithaca, NY 14853-6801, USA. Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA. Observatoire de la Cote d'Azur, Boite Postale 4229, 06034 Nice C.
概括
研究人员预测大约有900公里大小的近地小行星 (NEAs),其中40%被发现. 由于它们的轨道,许多剩余的NEAs很难被检测到.
科学领域:
- 天文学和天体物理学
- 行星科学 行星科学
- 轨道动力学 轨道动力学
背景情况:
- 接近地球的小行星 (NEAs) 存在潜在的撞击风险,是了解太阳系演变的关键.
- 目前的NEA目录是不完整的,特别是对于较小或动态不同的种群.
研究的目的:
- 为了确定NEA的轨道和尺寸分布.
- 估计公里大小的NEAs的总人口,并评估当前调查的完整性.
主要方法:
- 从源区域到观测轨道的NEAs的数值集成.
- 估计各种轨道上的小行星的观测偏差和尺寸分布.
- 开发一个模型人口,以适应已知的NEA数据.
主要成果:
- 据估计,有900个绝对等级<18 (公里大小) 的NEAs存在.
- 其中大约29%位于阿莫尔轨道,65%位于阿波罗轨道,6%位于阿顿轨道.
- 据估计,已经发现了大约40%的千米大小的NEAs,其余的位于难以检测的轨道上.
结论:
- 目前的NEA群体被大大低估了,特别是在离心轨道和倾斜轨道上的物体.
- 对于居住在难以进入轨道区域的NEAs,需要改进检测策略.
- 这项研究提供了对潜在危险小行星的更准确的普查.
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