The properties of ice giant normal mode oscillations, including their periods, spatial structure, stratospheric amplitudes and relative influence on the external gravity field, are surveyed for the purpose of formulating the best strategy for their eventual detection. Measurement requirements for detecting a normal mode's periodic pressure and temperature variations, including a possible stratospheric signal, and its effect on the external gravity field, are discussed in terms of its radial velocity amplitude at the 1 bar pressure level. It is found that for reasonable amplitudes, detection of the pressure and temperature variations of ice giant normal modes presents an extraordinary technical challenge. The prospects for detecting their gravitational influence on an orbiting spacecraft are more promising, with requirements that lie within the range of current technology. This article is part of a discussion meeting issue ‘Future exploration of ice giant systems’.

中文翻译：

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冰巨震学：正常模式勘探

调查了冰巨常模振荡的周期、空间结构、平流层振幅和对外部重力场的相对影响等特性，以制定最终检测的最佳策略。检测正常模式的周期性压力和温度变化的测量要求，包括可能的平流层信号，及其对外部重力场的影响，在 1 bar 压力水平下的径向速度幅度方面进行了讨论。研究发现，对于合理的振幅，冰巨常模的压力和温度变化的检测提出了非凡的技术挑战。探测它们对轨道航天器的引力影响的前景更有希望，具有当前技术范围内的要求。本文是讨论会问题“冰巨星系统的未来探索”的一部分。