在过去的1000万年里,太阳与冷云相遇时,辐射的增加和变化
Merav Opher1, Joe Giacalone2, Abraham Loeb3
1Astronomy Department, Boston University, Boston, MA, 02215, USA. mopher@bu.edu.
Scientific reports
|February 11, 2026
概括
地球经历了来自能量粒子的强烈辐射,当太阳.
科学领域:
- 太空物理学和天体物理学
- 古气候学 古气候学
- 天体生物学 天体生物学
背景情况:
- 证据表明,太阳在2-700万年前遇到了星际云,可能会缩小日球.
- 这些事件可能使地球接触到增加的宇宙辐射,由地质同位素 (60Fe,244Pu) 支持.
- 天球通常保护地球免受星际辐射.
研究的目的:
- 为了研究地球在日球收缩事件中经历的辐射的性质和强度.
- 量化暴露于热球能量粒子 (HEPs) 和银河系宇宙射线 (GCRs) 的数量.
- 讨论这种可变辐射对地球气候和生物多样性的潜在影响.
主要方法:
- 对地质同位素数据 (60Fe,244Pu) 的分析,以推断过去的太阳事件.
- 在日球探险期间的粒子辐射暴露的建模.
- 过去辐射强度与当前太阳能粒子 (SEP) 和GCR事件的比较.
主要成果:
- 在日光圈收缩期间,地球暴露在更高水平的能量粒子中.
- 球能量粒子 (HEP) 至少比今天的极端SEP强度高出一个数量级,持续数月.
- 银河系的宇宙射线暴露也至少比当前水平高出一个数量级.
结论:
- 地球的环境经历了长时间的高度可变和强烈的高能粒子辐射.
- 这些辐射事件代表了一个重要的外部驱动因素,对气候和生命有潜在的影响.
- 需要进一步的研究才能充分理解这些古老的辐射事件对地球历史的影响.
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