水星上的明亮和黑暗的极地沉积物:表面挥发物质的证据
Gregory A Neumann1, John F Cavanaugh, Xiaoli Sun
1NASA Goddard Space Flight Center, Code 698, Greenbelt, MD 20771, USA. gregory.a.neumann@nasa.gov
概括
水星北极附近的表面沉积物显示出明亮和黑暗的区域. 这些区域可能是水冰和绝缘有机物质,可能是由彗星带来的.
科学领域:
- 行星科学 行星科学
- 天文学 天文学
- 表面地质物理学 表面地质物理学
背景情况:
- 在水星极点附近的永久阴影区域 (PSR) 是挥发性物质的潜在储库.
- 雷达观测表明,在这些地区存在近地表水冰.
研究的目的:
- 调查水星北极PSR中异常表面沉积物的组成和起源.
- 为了将表面反射性能与热模型和雷达反射相关联.
主要方法:
- 在1064纳米波长的表面反射度测量的分析.
- 反射率数据与模拟的表面温度的相关性.
- 将反射率异常与高雷达背散射区域进行比较.
主要成果:
- 观察到的反射异常,无论是黑暗的还是明亮的,都集中在面向极点的斜坡上.
- 光学上明亮的区域与地表水冰相一致.
- 光学上黑暗的区域表明表面层的复杂有机物质覆盖埋藏的冰.
结论:
- 观察到的沉积物很可能是水冰和有机物质的混合物.
- 彗星或小行星撞击是这些沉积物的潜在来源.
- 有机物质可以为地下冰提供隔热.
相关概念视频
Dark Triad and Person Perception
299
Person perception is influenced by both external behaviors and the observer’s internal characteristics, including personality traits. Individuals with dark personality traits, comprising psychopathy, Machiavellianism, and narcissism — collectively known as the dark triad – exhibit manipulative and exploitative tendencies in social contexts. These traits affect how they perceive others and how they are perceived.The Role of Dark Personality Traits in Person PerceptionBlack et...
299
The Evidence for Evolution
48.1K
Genetic variations accumulating within populations over generations give rise to biological evolution. Evolutionary changes can result in the formation of novel varieties and entire new species. These changes are responsible for the diverse forms of life inhabiting the planet. The evidence for evolution suggests that all living organisms descended from common ancestors.
48.1K
Group Polarization
39.2K
Group polarization is the strengthening of an original group attitude following the discussion of views within a group (Teger & Pruitt, 1967). That is, if a group initially favors a viewpoint, after discussion the group consensus is likely a stronger endorsement of the viewpoint. Conversely, if the group was initially opposed to a viewpoint, group discussion would likely lead to stronger opposition.
39.2K
Volatilization
6.2K
Volatilization gravimetry is an analytical technique that measures the mass lost due to the volatilization of the substance. This technique is used to estimate the amount of volatile material in a sample. To perform this method, heat a known amount of the sample to a high temperature in a crucible or other suitable vessel. The volatile substance in the sample evaporates, and the vapor is completely expelled from the crucible either by heating the sample or bubbling a stream of inert gas through...
6.2K
Molecular Shape and Polarity
75.6K
Dipole Moment of a Molecule
75.6K
Phase Transitions: Sublimation and Deposition
20.2K
Some solids can transition directly into the gaseous state, bypassing the liquid state, via a process known as sublimation. At room temperature and standard pressure, a piece of dry ice (solid CO2) sublimes, appearing to gradually disappear without ever forming any liquid. Snow and ice sublimate at temperatures below the melting point of water, a slow process that may be accelerated by winds and the reduced atmospheric pressures at high altitudes. When solid iodine is warmed, the solid sublimes...
20.2K


