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彗星41P/Tuttle-Giacobini-Kresák的旋转速度迅速下降

Dennis Bodewits1, Tony L Farnham1, Michael S P Kelley1

  • 1Department of Astronomy, University of Maryland, College Park, Maryland 20742, USA.

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|January 12, 2018
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概括
此摘要是机器生成的。

对彗星41P/Tuttle-Giacobini-Kresák的观测显示了它的旋转速度大幅放缓. 这种由排气引起的旋转速率的快速变化表明彗星正在接近不稳定状态.

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科学领域:

  • * 星球科学
  • * 彗星动力学
  • * 天体物理学

背景情况:

  • *彗星的排气产生扭矩,改变彗星核的旋转状态,影响它们的进化和寿命.
  • * 快速旋转可能会导致核碎片化,因为材料的强度超过了离心力.
  • *减速的扭矩可能会破坏旋转状态,可能导致重定向和随着时间的推移增加旋转速率.

研究的目的:

  • * 为了研究彗星41P/Tuttle-Giacobini-Kresák在接近地球时的自旋动力学.
  • * 观测和量化彗星核心旋转速度的快速变化.
  • * 了解观察到的旋转状态变化对彗星进化和稳定的影响.

主要方法:

  • 在2017年近距离接近彗星41P/Tuttle-Giacobini-Kresák时进行的光度观测.
  • *对两个月的周期变化进行分析 (2017年3月至5月).
  • 在彗星排气扭矩的背景下观察到的旋转速率变化的解释.

主要成果:

  • * 彗星41P/Tuttle-Giacobini-Kresák的旋转速度显著下降.
  • 在两个月内,明显的旋转时间从20小时增加到46小时以上.
  • * 这一观察到的回转率比以前测量的数量大得多.

结论:

  • * 观察到的快速回转是由于排列气体发出异常强的扭矩引起的.
  • * 彗星41P/Tuttle-Giacobini-Kresák可能处于一个不同的进化阶段.
  • * 核的旋转可能接近不稳定点,可能导致碎片化或重定向.