Investigating Constraints on Induction in Cryospheres with a Lander for Electromagnetic Sounding (ICICLES)

我们建议开发一种远程操作的大地电磁（MT）着陆器，具有自主收集冰卫星表面电场和磁场数据的能力，这些冰卫星在行星科学中特别感兴趣，因为它们的海洋世界可能支持生命。来自冰冷卫星的大地电磁数据将对冰冻圈的横向可变厚度和内部结构以及其内部海洋的盐度、温度和环流提供强有力的限制，而这些仅凭轨道磁力计数据是无法确定的。帝国航空的空间实验室团队在开发用于航天器磁场观测的磁力计方面拥有丰富的经验。挑战将是开发连接到电极的大地放大器，能够自主部署，以测量冰冷卫星高电阻表面的电场。基于计算机模型，我们将致力于开发一种系统，该系统以128 Hz采样，并检测>1 nT的磁波动和>1 µV/m的电信号。MT是一种成熟的地球物理方法，可以深入了解大陆和海底以下的地壳和地幔电导率结构，但是需要对现有技术进行修改，以解决冰卫星表面预期的高冰电极接触电阻、自主部署方式和操作温度范围。要解决的特定问题将是如何以足够的空间间隔自主地部署电极，以确保在电极和大地放大器噪声源上方可检测到自然电场（通过将成对电极之间的电势差除以它们的间距来测量）波动。可能的解决方案是以弹道方式或在吊杆上部署电极。因此，我们将在斯瓦尔巴特群岛上采用不同的电极设计、大地测量长度、部署方式和机制进行冰上测量，这将是我们研发计划成功的关键。数据将通过GPS进行传输，这是现代MT系统的标准。我们评估了我们提出的系统目前的技术准备水平介于TRL 1和TRL 2之间。我们将在实验室和斯瓦尔巴群岛上测试我们的MT着陆器，在项目结束时将我们的技术提升到TRL 5级。我们预计在项目结束前几个月申请后续资金，使我们能够将我们的MT原型开发到下一阶段，这应该包括在外星环境中进行测试（例如，在月球上）。

We propose to develop a remotely operated magnetotelluric (MT) lander with autonomous capability to collect electric and magnetic field data on the surface of icy moons, which are of particular interest in planetary science, because their ocean worlds may support life. MT data from icy moons would provide robust constraints on the laterally variable thicknesses and internal structures of their cryospheres and the salinities, temperatures and circulation of their internal oceans that are indeterminable from orbital magnetometer data alone.Imperial's space laboratory team has extensive experience of developing magnetometers for spacecraft observations of magnetic fields. The challenge will be to develop telluric amplifiers connected to electrodes capable of being deployed autonomously to measure electric fields on the highly resistive surfaces of icy moons. Based on computer models, we will be aiming to develop a system that samples at 128 Hz and detects magnetic fluctuations >1 nT and electric signals >1 µV/m.MT is a well-established geophysical method that has provided insight into Earth's crustal and mantle electrical conductivity structure below continents and the seafloor, but modifications to available technology will be required to address the high ice-electrode contact resistance expected on the surface of icy moons, autonomous deployment style and operating temperature range. A particular question to address will be how to deploy the electrodes autonomously at sufficient spatial separations to ensure that natural electric field (measured by dividing the potential differences between paired electrodes by their distance apart) fluctuations are detectable above the sources of electrode and telluric amplifier noise. Possible solutions are to deploy electrodes ballistically or on booms. Therefore, measurements on ice that we will carry out on Svalbard with different designs of electrodes, telluric lengths, deployment styles and mechanisms will be central to the success of our research and development program. Data will be transmitted by GPS, which is standard on modern MT systems.We assess the current technology readiness level of our proposed system to lie between TRL1 and TRL2. We will test our MT lander both in the laboratory and on Svalbard, advancing our technology to a rating of TRL5 by the end of the project. We anticipate applying for follow-on funding a few months prior to the end of the project to enable us to develop our MT prototype to the next stage, which should include testing in an extraterrestrial environment (e.g., on the Moon).