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来自一个恒星的分子气体的聚合喷射在非对称巨型分支上的恒星
Hiroshi Imai1, Kumiko Obara, Philip J Diamond
1VERA Project Office, National Astronomical Observatory, Mitaka, Tokyo 181-8588, Japan. imai@jive.nl
Nature
|June 21, 2002
概括
天文学家检测到来自恒星W43A的分子气体的聚合,预处理喷气. 这一发现解释了恒星在过渡阶段如何形成延长的行星星云.
科学领域:
- 天文学和天体物理学
- 恒星进化 恒星进化
- 天体化学是天体化学.
背景情况:
- 进化的恒星 (大约. 1太阳质量) 通常是球形的.
- 星球星云通常表现出不对称性,而不是球形对称性.
- 在行星星云中观察到结合式喷流和外流,前行被认为是对不对称性的解释.
研究的目的:
- 调查行星星云中的不对称的起源.
- 确定行星星云中的协同喷射背后的机制.
- 为喷气形成的理论模型提供观测证据.
主要方法:
- 使用水蒸气质量仪斑点检测分子气体.
- 从恒星W43A.观测到一个喷气流,距离恒星W43A.大约500天文单位 (au).
- 对喷气式聚合和前进的分析.
主要成果:
- 检测一个聚合和预处理的分子气体喷气.
- 喷气是由W43A恒星附近的水蒸气质光子斑点追踪的.
- 喷射源于靠近中心恒星的地方.
结论:
- 观测到的射流是在恒星的直接附近形成的.
- 延长的行星星云很可能是由这样的喷气形成的.
- 这个过程发生在短的原行星星云阶段 (不到1000年).
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