流動性のある窒素氷の層は 冥王星の地質的な活力を駆動する
William B McKinnon1, Francis Nimmo2, Teresa Wong1
1Department of Earth and Planetary Sciences and McDonnell Center for the Space Sciences, Washington University in St Louis, Saint Louis, Missouri 63130, USA.
Nature
|June 3, 2016
まとめ
冥王星のスプートニク・プラニュムは,窒素の氷の層の固体コンベクションにより地質活動を示す. 熱流によって引き起こされる このプロセスは 氷の表面を形作り 他の矮星でも起こります
科学分野:
- 惑星科学
- 地理学
- 氷河学
背景:
- 冥王星のスプートニク・プランウムは 主に窒素という 揮発性氷で満たされた 大きな盆地です
- 流域の表面は,内部の地質活動を示唆するコンベクション細胞に編成されています.
研究 の 目的:
- スプートニク・プランウムの窒素氷層の 固体コンベクションの可能性を調査する
- 冥王星の表面に 観測されたコンベクション細胞の規模を説明するために
主な方法:
- 窒素氷の利用可能なレオロギー測定の分析
- 数値モデリング 流動的な転覆 数キロの厚さの窒素の氷層
主要な成果:
- 窒素の氷の層は,約1キロメートル厚さで,現在の熱流の条件下で,冥王星にコンベクトを予測しています.
- 数学的シミュレーションにより,コンベクティブ・ウーバーターンは,スプートニク・プランウムの表面細胞の大きな横幅を説明できる.
- 氷層は"緩やかな蓋"状態でコンベクトし,太陽系の他の場所では決定的に観察されていません.
結論:
- 固体コンベクションは,スプートニク・プランウムの地質学的活動の主な要因です.
- 冥王星の表面の再生は 表面の推定年齢より短い時間スケールで起こります
- 同様のコンベクティブプロセスは,他のカイパーベルトの矮惑星の高いアルベドを説明する可能性がある.
関連する概念動画
Phase Transitions: Sublimation and Deposition
20.7K
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...
20.7K
Volatilization
6.3K
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...
6.3K
Phase Transitions: Vaporization and Condensation
22.0K
The physical form of a substance changes on changing its temperature. For example, raising the temperature of a liquid causes the liquid to vaporize (convert into vapor). The process is called vaporization—a surface phenomenon. Vaporization occurs when the thermal motion of the molecules overcome the intermolecular forces, and the molecules (at the surface) escape into the gaseous state. When a liquid vaporizes in a closed container, gas molecules cannot escape. As these gas phase molecules...
22.0K
Isothermal Processes
5.3K
A thermodynamic process that occurs at constant temperature is called an isothermal process. Heat slowly flows into the system or out of the system to maintain thermal equilibrium. Processes involving phase changes like water evaporation into steam or freezing water into ice at a constant temperature are examples of Isothermal Processes.
An ideal gas can also undergo isothermal expansion or compression.
For example, consider 1 mole of an ideal gas inside an isolated cylinder at initial volume V...
An ideal gas can also undergo isothermal expansion or compression.
For example, consider 1 mole of an ideal gas inside an isolated cylinder at initial volume V...
5.3K
The Nitrogen Cycle
61.3K
Nitrogen atoms, present in all proteins and DNA, are recycled between abiotic and biotic components of the ecosystem. However, the primary form of nitrogen on Earth is nitrogen gas, which cannot be used by most animals and plants. Thus, nitrogen gas must first be converted into a usable form by nitrogen-fixing bacteria before it can be cycled through other living organisms. The use of nitrogen-containing fertilizers and animal waste products in human agriculture has greatly influenced the...
61.3K
Acceleration due to Gravity on Other Planets
5.1K
The gravitational acceleration of an object near the Earth's surface is called the acceleration due to gravity. It can be measured by conducting simple experiments on Earth. However, such an experiment is impossible to conduct on the surface of other planets.
Astronomical observations are thus used to measure the acceleration due to gravity on other planets. This can be determined by observing the effect of a planet's gravity on objects close to it. The crucial factor that helps in this...
Astronomical observations are thus used to measure the acceleration due to gravity on other planets. This can be determined by observing the effect of a planet's gravity on objects close to it. The crucial factor that helps in this...
5.1K


