Comparative planetary seismology across the telluric planets

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Project BackgroundWith the successful deployment and operation of the InSight geophysical mission on Mars (see Banerdt et al 2020 and Lognonné et al 2020), and proposals to put new geophysical equipment on the Moon, we have entered a new era of planetary seismology. Nonetheless, there is a great deal of uncertainty regarding both the internal structures of the telluric, or rocky, planets in our solar system and the seismic probes which might best illuminate these bodies. Good models exist for some planetary interiors, but other planets and moons remain poorly modelled.However, a wealth of new tools are now available to understand both instrumented and un-explored planetary interiors. This project will apply Earth-tested seismological modelling to existing models of planetary interiors to understand what information we can glean from existing data and deployments, as well as making predictions on what might be possible elsewhere in our solar system.Project Aims and MethodsThere is a strong interest in planetary interiors at the University of Bristol. This seismological project will focus on investigating seismic data from Mars, the Moon, and Earth, and simulating data on a range of different planets. The target planets will depend on the interests of the student, but are likely to include Venus and Mercury as well as those planets from which we have seismological data. Questions the project will seek to answer include:How would Mercury/Venus look to a seismologist?Which seismic phases are particularly sensitive to the properties of non-terrestrial planetary cores?What are the similarities and differences between seismic observables for different viable models of telluric planets? Are there some observations which are always useful?To answer these, and similar, questions a range of different tools will be used. Beyond ray-theoretical predictions of seismic waves travelling through planets, it is now possible to simulate the full wavefield generated by a seismic event, whether through a spherically symmetric model, or a more complex planet (Nissen-Meyer et al 2014, Leng et al 2019). Mineral physics has provided new data and Equations of State which can be incorporated into the modelling of planetary interiors using appropriate software (e.g. Connelly 2009, Cottaar et al 2014).The project will involve assessing seismic data which already exists from the Apollo missions, examining new data available from the InSight mission's VBB sensor, and also assessing similar data from the Earth where needed. Modelling planetary interiors based on reasonable putative planetary compositions may be important depending on the direction this project takes.