由于DART动力冲击而导致的Dimorphos轨道周期变化
Cristina A Thomas1, Shantanu P Naidu2, Peter Scheirich3
1Northern Arizona University, Flagstaff, AZ, USA. cristina.thomas@nau.edu.
Nature
|March 1, 2023
概括
双重小行星重定向测试 (DART) 任务成功改变了一个小行星的轨道. 太空船的动力冲击缩短了Dimorphos的轨道周期33分钟,远远超过预测.
科学领域:
- 星球科学
- 天体动力学
- 撞击物理
背景情况:
- 双重小行星重定向测试 (DART) 任务旨在测试小行星偏移的动力冲击器技术.
- 这项史无前例的实验的目标是小行星迪迪莫斯的一个月亮.
- 使用多年的光曲线观测精确确定了撞击前的轨道参数.
研究的目的:
- 报告DART动力冲击后Dimorphos轨道周期的测量变化.
- 分析动量转移及其对小行星轨道的影响.
- 调查喷射物在增强动力转移中的作用.
主要方法:
- 使用光曲线观测精确确定撞击前的轨道参数.
- 使用地球光曲线和雷达观测来测量撞击后的轨道周期变化.
- 分析了冲击动态,考虑了动量增强因素.
主要成果:
- 迪莫尔福斯的轨道周期变化为-33.0 ± 1.0 (3σ) 分钟.
- 两个独立的观测方法 (光曲线和雷达) 对周期变化产生了相同的结果.
- 观察到的周期变化明显大于完全不弹性碰撞的预测.
结论:
- DART的动力冲击成功地转移了小行星Dimorphos.
- 实质性的轨道周期变化表明了超出了飞船的冲动动量的显著增强.
- 在撞击过程中产生的喷射在增加动量转移中发挥了关键作用,为观察到的偏移做出了贡献.
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