概括
火星的极地观测显示,剩余盖是水冰,而不是二氧化碳. 接近205K的温度和43%的度是夏末这个冰冷沉积物的特征.
科学领域:
- 行星科学 行星科学
- 火星科学 火星科学
- 极地科学 极地科学
背景情况:
- 火星极地区域的组成和热特性对于了解火星气候历史至关重要.
- 以前的观测表明,火星极点上存在水冰和二氧化碳冰.
研究的目的:
- 为了确定夏季末火星北极残留帽的组成和温度.
- 为了调查永久二氧化碳极地盖的存在或不存在.
主要方法:
- 宽带热观测用于测量表面温度.
- 反射光谱测量以确定表面的白度和组成.
主要成果:
- 剩余极地帽的温度被测到大约在205K.
- 阿尔贝多测量表明值约为43%.
- 顶部和周围的沉积物被确定为含有污垢的水冰.
- 没有发现永久的二氧化碳极地盖的证据.
结论:
- 火星的北极残余盖是由水冰和泥土组成的.
- 在夏末,北极没有永久的二氧化碳冰盖.
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