Unveiling the interior of planetary bodies, from geodesy to the search for habitable environments
An in-person workshop for PhD students and early-career researchers on how gravity, tidal and magnetic data are turned into models of planetary interiors.
A hands-on workshop on forward modelling and Bayesian inversion of planetary interiors.
Gravity fields, tidal deformation and induced magnetic fields are most of what we can measure about the inside of a planet or a moon. Linking them to a model of the interior means solving two problems. The forward problem predicts what a given internal structure would produce. The inverse problem works back from the data to the set of structures that fit them, and to how well each parameter is constrained.
Juno has measured the tidal response of Io, and JUICE and Europa Clipper will return gravity, altimetry and magnetic data for Ganymede, Europa and Callisto. Reading these data requires numerical models that couple non-linear rheology, heat transport and multiphase dynamics, together with statistical methods that can handle the non-uniqueness of the solution.
The workshop brings together about 20 PhD students and young postdocs. Each part of the programme starts with lectures and continues with a hands-on session: participants build a finite element model, then run a Markov chain Monte Carlo inversion on synthetic data. A final round table looks at how the uncertainties on interior parameters translate into ice shell thickness, ocean depth and dissipated tidal power, which are the quantities that matter when assessing whether an ocean world could be habitable.
From the measurements to the models and back.
Gravity field, moment of inertia, Love numbers and induced magnetic fields, and how radio science, laser altimetry and magnetometry measure them.
Conservation equations, convection, viscoelastic and visco-elasto-plastic rheology, multiphase systems. Hands-on finite element modelling.
Likelihood, non-uniqueness and uncertainty quantification. Hands-on MCMC inversion of structural parameters from simulated data.
From interior parameters to ocean depth, crust thickness and dissipated power, and ideas for joint work after the workshop.
The workshop is organised by researchers at INAF-IAPS and Sapienza University of Rome. Travel grants for participants are funded by the Società Italiana di Scienze Planetarie Angioletta Coradini (SISP-AC).
Lectures first, then hands-on work on the same topics.
The first phase covers the observables that constrain the interior of a body and the techniques used to acquire them: radio science based on spacecraft tracking, laser altimetry and magnetometry. For each one we discuss the quantitative link between the measurement and the internal properties it is sensitive to.
The second phase introduces physical models of planetary interiors built from conservation equations, with attention to the rheology of rock and ice and to systems where melt or water coexist with a solid matrix.
Building a finite element model, with boundary conditions and constitutive laws chosen for a real planetary body.
The third phase moves from data to models. Participants see how to write a likelihood for geophysical observables, how to explore a parameter space where many solutions fit the data, and how to report the resulting uncertainties.
Running a Markov chain Monte Carlo algorithm to infer structural parameters from a simulated dataset.
The uncertainties on interior parameters are carried over to quantities of astrobiological interest, such as ocean depth, crust thickness and dissipated power. The discussion is also the place to plan joint projects among participants and speakers.
Lecture notes, example codes for modelling and inversion and the synthetic datasets used in the hands-on sessions will be shared with participants.
About 20 places, assigned on the basis of CV and motivation.
Aged 35 or under at the time of the workshop.
The application asks for a short CV and a motivation statement.
Applications are evaluated on CV and motivation. In forming the group we also look for participants from different Italian institutions and for gender balance, and we give attention to applicants with limited funding for travel.
The Società Italiana di Scienze Planetarie Angioletta Coradini (SISP-AC) funds four to five SISP-AC Travel Grants, which cover travel and accommodation for selected participants. You can ask for one in the application form.
Practical details for planning your trip.
The workshop is held in person.
Rome is served by Fiumicino and Ciampino airports, and Roma Termini is the main railway station, with high-speed trains to most Italian cities. Directions to the venue will be posted here once the room is confirmed.
Participants arrange their own accommodation. Those who receive a travel grant will get the details on what is covered together with the notification of selection.
A laptop for the hands-on sessions. Instructions for installing the software used in the exercises will be sent to selected participants before the workshop.
The people behind the workshop.
INAF, Istituto di Astrofisica e Planetologia Spaziali (IAPS)
Sapienza University of Rome, Department of Mechanical and Aerospace Engineering