在泰坦的上层大气层中,托林形成的过程
J H Waite1, D T Young, T E Cravens
1Space Science and Engineering Division, Southwest Research Institute (SWRI), 6220 Culebra Road, San Antonio, TX 78238, USA. hwaite@swri.edu
概括
泰坦 泰坦 泰坦 泰坦 泰坦
科学领域:
- 行星科学 行星科学
- 天体化学是天体化学.
- 大气化学 大气化学
背景情况:
- 泰坦的大气中含有有机气溶,称为tholins.
- 以前,人们认为托林在较低的海拔上形成.
- 在高海拔地区的形成过程没有被观察到.
研究的目的:
- 为了研究泰坦大气中的托林的形成.
- 为了确定托林形成的高度和化学途径.
- 为了描述托林前体的性质.
主要方法:
- 利用卡西尼航天器的质量/电荷和能量/电荷光谱仪.
- 分析了大气物种的化学成分和分子质量.
- 在高海拔地区研究离子化学.
主要成果:
- 在约1000公里的海拔上,有托林形成的证据.
- 观察到从简单分子 (甲,) 到复杂有机物 (80-350 Da) 的化学途径.
- 检测到巨大的负电荷分子 (约8000Da),被确定为tholins.
结论:
- 索林形成发生在泰坦大气中意想不到的高度.
- 这个过程涉及复杂的化学反应,形成大,负电荷的分子.
- 这一发现挑战了关于托林起源和泰坦大气化学的先前假设.
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