概括
研究人员估计奥尔特云的存在.
科学领域:
- 天文学和天体物理学
- 行星科学 行星科学
背景情况:
- 奥尔特云是围绕太阳系的理论上的彗星球形云.
- 估计奥尔特云的质量和角动量对于理解太阳系的形成和演变至关重要.
- 以前的模型经常将奥尔特云视为冰体的均分布.
研究的目的:
- 估计彗星核在3×10^3到2×10^4AU的日中心距离范围内未见的质量.
- 为了确定奥尔特云的质量和角动量.
- 为了比较奥尔特云的质量和角运动量与早期太阳系和当前行星系统.
主要方法:
- 基于彗星核的模拟看不见的质量分布.
- 假设奥尔特云是围绕着密集的内彗星云的稀释光环.
- 使用哈雷彗星的质量和白度作为彗星群体的典型表示.
主要成果:
- 彗星核的估计质量在3×10^3和2×10^4AU之间,大约是0.03太阳质量.
- 这个区域的角动量估计为10^52到10^53g-cm^2/s.
- 奥尔特云可能包含大约100个地球质量 (M),其角动量可能超过当前行星系统的一个数量级.
结论:
- 奥尔特云的质量相当于早期太阳系在挥发性损失之前的总质量.
- 奥尔特云的角动量是显著的,可能与早期行星系统的角动量相竞争.
- 这些发现为外太阳系中质量和角动量的分布提供了新的见解.
相关概念视频
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