火星大气侵蚀的速度是多少
Stas Barabash1, Andrei Fedorov, Rickard Lundin
1Swedish Institute of Space Physics, Box 812, 98128 Kiruna, Sweden. stas@irf.se
概括
火星失去了它古老的二氧化碳大气层进入太空. 目前的太阳风相互作用显示,逃逸率很低,这表明火星表面下仍可能存在大量的水和二氧化碳.
科学领域:
- 行星科学 行星科学
- 大气科学 大气科学
- 天体生物学 天体生物学
背景情况:
- 火星从一个可能宜居的潮湿环境过渡到目前的干旱状态.
- 了解火星早期二氧化碳大气的丧失对于行星进化研究至关重要.
研究的目的:
- 量化目前来自火星的关键物种的大气逃生率.
- 在地质时间尺度上估计总大气损失.
- 调查对地球古代气候和潜在可居住性的影响.
主要方法:
- 由于太阳风相互作用而产生的离子逃逸率 (O+,O2+,CO2+) 的测量.
- 在35亿年内推算出当前逃逸率.
- 分析的能量范围从30到30,000 eV/充电.
主要成果:
- 当前的逃逸速度:O+ (1.6x10^23/s, 4 g/s),O2+ (1.5x10^23/s, 8 g/s),CO2+ (8.10^22/s, 6 g/s).目前的逃逸速度是:O+ (1.6x10^23/s, 4 g/s),O2+ (1.5x10^23/s, 8 g/s),CO2+ (8.10^22/s, 6 g/s).目前的逃逸速度是:O+ (1.6x10^23/s, 4 g/s),O2+ (1.5x10^23/s, 8 g/s),CO2+ (8.10^22/s, 6 g/s).目前的逃逸速度是:O+ (1.6x10^23/s, 4 g/s),O2+ (1.5x10^23/s, 8 g/s),CO2+ (8.10^22/s, 6 g/s) 等.
- 估计在35亿年内,0.2-4毫巴二氧化碳和几厘米水的总去除.
- 总体大气逃逸率被确定为低.
结论:
- 低计算的大气损失表明,大量的水和二氧化碳储备可能会在火星表面下存在.
- 需要进一步的研究来探索地下水库和其他大气逃生机制.
- 这些发现挑战了关于火星早期大气层完全消失的先前假设.
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