Postdoc Icy Moons and their Oceans

Join the ERC LeakingOceans team to uncover how hidden oceans on icy moons reach the surface and what this reveals about their composition, dynamics and accessibility.

Job description

We are pleased to announce one postdoc position within the newly awarded ERC Advanced Grant LeakingOceans. This interdisciplinary project aims to reveal how the hidden oceans of icy moons, such as Enceladus, Europa and Ganymede, interact with their surfaces. Although these oceans are unreachable today, they leak through the moons’ icy crust, providing natural access to their composition and dynamics. Previous missions have shown that subsurface oceans reach the surface through several processes, and LeakingOceans aims to understand, quantify and detect these leaks and the ocean materials they deliver.

About the LeakingOceans ERC Project

Most oceans in our Solar System lie beneath kilometres of ice. On Enceladus, one moon of Saturn, observations have revealed that its subsurface ocean escapes through geysers or plumes via crevasses in the icy shell, reaching the exosphere. These plumes, composed of icy grains and water vapour, were extensively studied during Cassini flybys. Analyses revealed that the grains are salty and contain complex organic molecules, indicating that Enceladus’ ocean holds key ingredients for life, such as water, salts and organics. Europa, a moon of Jupiter, may also host plume activity, although the evidence is less certain. Hubble observations suggest intermittent, smaller plumes. However, surface fractures on Europa indicate that its ocean can reach and spill onto the surface. Together, plumes and cracks offer exceptional opportunities to study these hidden oceans.

Recent JWST observations have revealed fine spatial and spectral variations in icy moon surfaces. For example, the CO₂ band on Ganymede and Europa appears in multiple components, indicating diverse structural ice states that could be linked to a subsurface origin. These features cannot be interpreted with existing laboratory data, as it is unknown if they belong to the microscopic (molecular level) or macroscopic (icy grains) state of the ice. This highlights the urgent need for experiments that reproduce ice formation and processes occurring on icy moons.

The goal of LeakingOceans is to determine the efficiencies, mechanisms and spectroscopic signatures of processes that bring oceanic material to moon surfaces. By combining laboratory experiments, quantum mechanical and radiative transfer modelling to compare with JWST data, this project will provide tools to identify where and how oceans leak to the surface, supporting the search for habitable environments beyond Earth.

About the Postdoc Position

This postdoctoral position focuses on the design, construction and scientific exploitation of a novel frozen droplet generator, a key experimental setup within the LeakingOceans project (building on Häusler et al. 2018). The goal is to produce well-calibrated frozen icy grain analogues on a microchip perforated with hemispherical cavities of defined sizes, allowing deposition of liquid droplets of controlled dimensions. Reflectance spectra from well-calibrated icy grain analogues submitted to different conditions, including temperature of formation and fluctuations, will serve as spectral references for interpreting JWST observations and supporting future JUICE mission data analysis.

The postdoc will work in close collaboration with the PhD and Postdoc students of the LeakingOceans team and will contribute to the:

• Design and construction of the frozen droplet generator.
• Execution of experiments producing size-controlled frozen droplets under icy moon conditions.
• Acquisition and analysis of reflectance spectra to build a grain spectral reference library.
• Comparison of laboratory spectra with JWST and JUICE observational data.

Job requirements

We are looking for a motivated researcher with:

• A PhD in experimental physics, planetary science, astrochemistry, physical chemistry, or a closely related field.
• Hands-on experience with vacuum systems, cryogenic equipment and optical setups.
• Experience with infrared spectroscopy (FTIR).
• Familiarity with icy moons science, planetary ices, or astrochemistry is a strong asset.
• Experience with instrument development or laboratory setup design is highly valued.
• Ability to work both independently and collaboratively within an interdisciplinary team.
• Excellent written and oral communication skills in English.

TU Delft as an employer

Delft University of Technology is a top international university combining science, engineering and design. It delivers world class results in education, research and innovation to address challenges in the areas of energy, climate, mobility, health and digital society.

The Faculty of Aerospace Engineering at Delft University of Technology is a leading international community where innovation in aerospace meets global challenges. Support and scientific staff, including PhD candidates, postdocs, and students, largely work together on three main themes: the energy transition, sustainable aerospace, and safety and security.

When you join, you become part of a collaborative and forward-thinking environment where ideas and perspectives are valued. The work extends beyond the lab into field labs, innovation hubs, and partnerships with other faculties, research institutes, governments, and industry, both locally and globally.

Conditions of employment

• Duration of contract is 3 years temporary.
• Salary and benefits are in accordance with the Collective Labour Agreement for Dutch Universities.
• An excellent pension scheme via the ABP.
• The possibility to compile an individual employment package every year.
• Discount with health insurers on supplemental packages.
• Flexible working week.
• Every year, 232 leave hours (at 38 hours). You can also sell or buy additional leave hours via the individual choice budget.
• Plenty of opportunities for education, training and courses.
• Partially paid parental leave.
• Attention for working healthy and energetically with the vitality program.
• If you need to relocate to the Netherlands for this job, TU Delft is committed to making your move as smooth as possible. The Coming to Delft Service offers information and events to help you prepare your relocation, settle in the Netherlands, and expand your social network in Delft. A Dual Career Programme is available to support your accompanying partner with their job search in the Netherlands.

As part of knowledge security, TU Delft conducts a risk assessment during the recruitment of personnel to prevent the unwanted transfer of sensitive knowledge and technology. The assessment is based on information provided by candidates, such as their motivation letter and CV, and takes place at the final stages of the selection process. When the outcome of the assessment is negative, the candidate will be informed.