Collaborative Research: GLOW: Basal magma ocean dynamos of early Earth, Venus, and the Moon

地球及其最近的邻居金星和月球的古代磁场的起源还不是很清楚。该项目旨在了解岩浆海洋产生的发电机是否能够维持地球早期的磁场。该项目还将确定发电机在金星上可能存在了多久，以及这种发电机是否导致了月球早期历史上的高强度磁场。对模型的所有修改都将对科学界开放源代码。这项工作将在公共广播节目EarthDate上播出。本科生将加入该团队，运行发电机模拟数值模型，培养数据分析技能和计算工具，以促进专业发展。在地核形成之前，类地行星和卫星的古代磁场的起源是一个长期存在的问题。基底岩浆海洋发电机被假设为解释地球如何能够在内核生长开始之前维持磁场的机制。该项目将研究早期地球、月球和金星最下层液态地幔与铁合金地核之间的动态和磁耦合程度和机制。该项目将确定基底岩浆海或岩心的稳定分层如何调节磁场的产生和衰减，以及这些储层之间的混合。该团队将在基底岩浆海和地核中模拟具有不同传输特性的发电机，如电导率、热扩散率和运动粘度。这些计算将决定基底岩浆海洋发电机是否能产生与观测条件一致的磁场。更好地表征类地行星和卫星的磁场产生将促进对系外行星基底岩浆海洋发电机的理解。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The origin of the ancient magnetic fields of Earth and its nearest neighbors, Venus and the Moon, is not well understood. The program will aim to understand if a dynamo generated by a magma ocean could have sustained Earth’s early magnetic field. The project will also determine for how long a dynamo may have existed on Venus and if such a dynamo was responsible for the high intensity magnetic field in the early history of the Moon. All modifications to the models will be open source for the science community. The work will be aired on the public service radio program EarthDate. Undergraduate students will join the team to run dynamo simulation numerical models, develop skills in data analytics and computational tools that will enhance professional development.The origin of ancient magnetic fields in terrestrial planets and moons prior to formation of the inner core is a long-standing question. Basal magma ocean dynamos have been hypothesized as mechanisms to explain how the Earth was able to maintain a magnetic field before the onset of inner core growth. This program will investigate the degree and mechanisms of dynamic and magnetic coupling between the lowermost liquid mantle and the iron-alloy core in the early Earth, the Moon and Venus. The project will determine how stable stratification in the basal magma ocean or core modulates magnetic field generation and attenuation, as well as mixing between these reservoirs. The team will simulate dynamos with different transport properties, such as electrical conductivity, thermal diffusivity, and kinematic viscosity, in the basal magma ocean and the core. These calculations will determine whether basal magma ocean dynamos can generate magnetic fields that are consistent with observational constraints. A better characterization of magnetic field generation in terrestrial planets and moons will advance the understanding of basal magma ocean dynamos in exoplanets.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.