一个原行星盘的彗星状组成,由复杂的化物揭示出来
Karin I Öberg1, Viviana V Guzmán1, Kenji Furuya2
1Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA.
Nature
|April 10, 2015
概括
在原行星盘中检测到复杂的有机分子,包括甲基化物 (CH3CN). 这一发现表明,我们太阳星云的有机丰富性并非独一无二,而是存在于早期恒星系统中.
科学领域:
- 天体化学是天体化学.
- 行星科学 行星科学
- 有机化学 有机化学
背景情况:
- 早期的太阳星云含有水和有机分子,由彗星和小行星运到地球.
- 彗星提供了太阳星云组成的原始记录,化物对非生物氨基酸合成至关重要.
- 虽然在原行星盘中发现了简单的挥发物,但复杂的有机分子的存在以前是不确定的.
研究的目的:
- 调查年轻恒星MWC480周围的原行星盘中复杂的化物的存在和丰富性.
- 为了比较这些分子的丰度比率与彗星中发现的.
- 了解行星系统早期化学库存的含义.
主要方法:
- 使用无线电天文学观察MWC 480周围的原行星盘的观测.
- 检测和量化特定的复杂化物,包括甲基化物 (CH3CN) 和乙烯 (HC3N).
- 对气相丰度比率的分析和与彗星数据的比较.
主要成果:
- 在MWC 480原行星盘中检测出甲基化物 (CH3CN),乙烯 (HC3N) 和化物 (HCN).
- 这些含有机物质的气相丰度比率与彗星中观察到的相似.
- 这种相似性表明,在磁盘的冰期内,复杂的化物的丰度可能更高.
结论:
- 复杂的有机分子,如化物,存在于原行星盘中,可能伴随着更简单的挥发物.
- 在我们的太阳星云中观察到的有机化学,对生命起源至关重要,很可能不是我们系统独有的.
- 这些发现支持这样一个观点,即生命的构建模块在新生行星系统中很常见.
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