根据对黑色地形的观察,泰坦上可能存在热带湖泊
Caitlin A Griffith1, Juan M Lora, Jake Turner
1Lunar and Planetary Laboratory, University of Arizona, Tucson, Arizona 85721, USA. griffith@lpl.arizona.edu
Nature
|June 16, 2012
概括
泰坦 泰坦 泰坦 泰坦 泰坦
科学领域:
- 行星科学 行星科学
- 天体生物学 天体生物学
- 大气科学 大气科学
背景情况:
- 泰坦拥有类似地球的特征,如云,雨和湖泊,但由甲组成.
- 泰坦的大多数甲是大气中的,表面液体只在高度上被检测到.
- 泰坦的热带地区的特点是沙丘场,而不是表面的液体.
研究的目的:
- 为了调查泰坦的低度地区表面液态甲的存在和起源.
- 分析光谱数据以了解泰坦表面特征的组成和特征.
- 为了使观察到的表面液体分布与大气模型相协调.
主要方法:
- 对近红外光谱图像的分析,涵盖从20°N到20°S的度.
- 在七个波长频段中确定表面光谱流量最低的区域.
- 辐射转移分析的应用,以解释表面的光谱特性.
主要成果:
- 在20°N和20°S之间确定了一个持久的圆区域 (60 × 40 km2),具有非常低的光谱流.
- 这个区域的光谱特征与黑色表面一致,表明存在液态甲.
- 这一发现挑战了关于泰坦表面液体分布的先前假设.
结论:
- 泰坦的持久的低度湖泊很可能来自地下来源,在过去的1万年里得到了补充.
- 这些地下来源可能是泰坦大气中甲的来源.
- 持续补充甲对于通过光化学过程维持泰坦的有机化学是至关重要的.
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