In order to apply for any of the following theses or internships, the candidate must have no more than 3 exams left.
Deep space navigation (tracking spacecraft beyond the lunar orbit) faces major challenges due to the absence of GNSS coverage and the limited availability of ground stations. Current systems, such as NASA’s Deep Space Network (DSN) and ESA’s ESTRACK, employ Very Long Baseline Interferometry (VLBI) for angular positioning. While effective, terrestrial VLBI is constrained by limited baselines, atmospheric distortions requiring calibration, and reduced target visibility caused by Earth’s rotation. To address these limitations, a novel approach based on space-based interferometry has been proposed. In this concept, signals from interplanetary spacecraft are received and cross-correlated by a constellation of Geostationary Earth Orbit (GEO) satellites. This configuration extends baselines, eliminates atmospheric phase errors, and provides near-continuous visibility, but demands extremely accurate orbit determination (OD) of the GEO platforms.
Activities:
Conduct a literature review on VLBI methods for deep space navigation.
Develop a simulation environment for GEO orbit determination using JPL’s MONTE toolkit.
Quantify achievable OD accuracies under different tracking configurations, including GNSS measurements, Doppler and range data from Earth stations, and hybrid duty-cycle scenarios.
This thesis combines advanced OD simulation, estimation theory, and mission design, contributing to future autonomous deep space navigation concepts.
Topic: Deep Space Navigation
Tutor: Riccardo Lasagni Manghi
Uploaded: 17/09/2025
Radio occultation is a powerful technique for studying the ionospheres of planets and moons, typically yielding key information such as electron density profiles. Existing analysis methods predominantly rely on the Abel inversion. This thesis proposal aims to develop a new methodology based on a least-squares approach, which offers greater flexibility if compared to traditional methods.
The least-squares approach enables the simultaneous fitting of the radio signal's phase data to a parameterized ionospheric model, allowing for the inclusion of additional constraints and prior knowledge about the system. Also, it allows for a rapid estimation of the uncertainties associated with the derived electron density profiles compared to time-consuming approaches such as Monte Carlo analyses.
The proposed methodology will be applied to the analysis of radio occultation data from NASA's Juno spacecraft, focusing on the ionospheres of the Galilean moons (Europa and Ganymede). By deriving high-fidelity electron density profiles, this work will contribute to a better understanding of the complex ionospheric environments of these moons, as well as their interactions with Jupiter's magnetosphere.
Topic: Radio Occultations / Numerical Computation
Tutor: Andrea Caruso
Uploaded: 25/02/2025
Hera is a European Space Agency space mission, aimed at conducting an in-depth investigation of the Didymos binary asteroid system following the impact of the DART spacecraft (NASA) on Dimorphos. One of Hera's primary objectives is to accurately estimate the mass and mass distribution of both asteroids. This entails determining the gravity field of Didymos and Dimorphos with precision, offering valuable insights into their overall mass and internal distribution.
To assess the expected accuracy in the gravity field of the asteroids, our approach involved tracking and modelling Hera, Juventas and Milani spacecrafts in orbit around the asteroids. This thesis introduces a complementary method to gauge the sensitivity to the asteroids' gravity field, following the approach adopted by OSIRIS-REx at Bennu. This method entails tracking, using spacecraft-based images, and modeling pebble-sized particles that might have been ejected from Dimorphos' surface after the DART impact, establishing sustained orbits, or following natural ejection. The candidate will utilize Python to model these particles and perform orbit determination using the MONTE (NASA-JPL) software.
Moreover, the candidate will conduct parametric analyses to evaluate the sensitivity of the results to key parameters. This involves exploring variations in particle size and number, as well as different observation schedules.
Topic: Planetary Defence / Data Analysis
Tutor: Edoardo Gramigna
Uploaded: 07/03/2024
Optical images collected by deep-space probes are often used to estimate the relative position of the spacecraft with respect to their small body targets.
This thesis aims to perform a detailed literature review of currently available image processing and navigation techniques for missions to small bodies, with a specific focus on the LiciaCube mission to the binary asteroid system Didymos.
The candidate will develop a complete pipeline for the most common image processing techniques, leading to the extraction of the target’s center of brightness and limb profile from a given input picture.
The generated observables will be included within JPL’s orbit determination software MONTE and analyzed as part of the LiciaCube flyby reconstruction.
Topic: Deep Space Navigation / Data Analysis
Tutor: Riccardo Lasagni Manghi
Uploaded: 09/02/2024
Context - The ESA planetary defense mission RAMSES will rendezvous with the near-Earth asteroid Apophis to characterize its physical properties. Onboard, the Radio Science Experiment (RSE), led by our team, will determine the asteroid's mass, gravity field, and spin state. In preparation, mission analysis simulations are quantifying its expected performance and scientific return.
Current simulation scenarios are based on shape and rotation models derived largely from ground-based photometric observations (lightcurves). However, these inversion solutions do not capture all physically plausible shapes and spin states: for non-convex shapes, different solutions can reproduce similar lightcurves. This limits our ability to robustly predict the full range of conditions that may be encountered at spacecraft arrival.
Objective - This project aims to investigate the non-uniqueness of lightcurve inversion solutions by exploring and analyzing alternative shape and rotation models that are still consistent with existing observations. This work will investigate how non-convex features (such as a possible bi-lobate shape or large concavities) influence the lightcurves and how they could affect the range of plausible spin states to be considered.
Activities
- Reproduce asteroid shapes and rotation solutions from the literature using available lightcurve inversion tools for convex shapes (e.g., convexinv), covering both regular rotation and tumbling bodies like Apophis.
- Generate synthetic lightcurves from non-convex shapes using common rendering tools (e.g., Blender) or more physics-based rendering methods.
- Find alternative non-convex shapes compatible with available observations, focusing on how specific features such as a possible bi-lobate shape, or large craters, affect the associated rotation solutions.
- Optional: Acquire and analyze your own lightcurves with the team’s equipment, focusing on previously visited asteroids (e.g., Vesta, Lutetia, Eros) to validate methods against known shapes.
Requirements
- Fluent written and spoken English* (for this topic, meetings will be held in English).
- Programming skills (e.g., Python) for data analysis and simulation.
- Nice to have: experience with rendering software (e.g., Blender).
Topics: Data Analysis / Numerical Simulations
Tutor: Pierre-Louis Phan
Uploaded: 24 March 2026