TEMPusVoLA

Planet-formation studies in microgravity

The interaction between dust particles and low-pressure gas is at the heart of many astrophysical and planetary phenomena. Notably, the activity of comets, and their presumed formation history, involves a deep understanding of dust–gas transport processes at low gas pressures. The TEMPus VoLA project was designed to replicate and study these interactions experimentally, in microgravity.

The origins of the Solar system

Formation processes of the early Solar System that are investigated in the context of the TEMPusVoLA project.
Comets and asteroids are planetesimals that remain from the formation of the Solar system. As we unravel their properties and dynamical behaviour, we also deduce the conditions in which they formed. Experiments in low-gravity environments allow direct investigations of the presumed mechanisms that enabled the first stages in forming planets (Capelo et al., 2025) and the ongoing processes on primordial bodies such as comets and asteroids (Capelo et al., 2024).

A novel Zero-G experimental facility

TEMPus VoLA: The Timed Epstein Multi-pressure Vessel at Low Accelerations flew aboard three parabolic flight campaigns on Air Zero-G, operated by Novespace. See apparatus details in (Capelo et al., 2022).
TEMPus VoLA (the 'Timed Epstein Multi-Pressure Vessel at Low Accelerations') is a dedicated microgravity facility designed to investigate gas–dust interactions at low pressures. The systems enable direct observation of dust-driven hydrodynamic instabilities, drag reduction phenomena, and dust-regolith mechanical properties under near-weightless conditions.

For photos of the pilot measurement campaign, see images from the Swiss Space Museum Album 1, and Album 2. Links to further media coverage can be found on the outreach page.

This work was initiated within the framework of the Swiss National Center for Competence in Research (NCCR) PlanetS. It involves researchers from the University of Bern, University of Zürich, and ETH Zürich. The project has benefitted from continuous support from the UZH Spacehub, the European Space Agency (ESA), and the Swiss Space Office (SSO).

References

2025

  1. Experimental evidence for granular shear-flow instability in the Epstein regime
    H. L. Capelo, J.-D. Bodénan, M. Jutzi, and 6 more authors
    Nature Communications Physics, (In Press), Dec 2025
    DOI

2024

  1. Gas permeability and mechanical properties of dust grain aggregates at hyper- and zero-gravity
    H. L. Capelo, J.-D. Bodénan, M. Jutzi, and 13 more authors
    Monthly Notices of the Royal Astronomical Society, Sep 2024
    DOI

2022

  1. TEMPus VoLA: The timed Epstein multi-pressure vessel at low accelerations
    H. L. Capelo, J. Kühn, A. Pommerol, and 12 more authors
    Review of Scientific Instruments, Oct 2022
    DOI