Experiments on Settling of Granular and Cohesive Material in Low Gravity
Abstract
The regolith of rocky bodies, such as planets or asteroids, generally settles under gravity conditions different from those of Earth. The behavior of granular material is not easily scalable for different gravities. To predict these highly complex systems where cohesive inter particle forces can be comparable to gravitational forces, we need simulations and experiments. We did experiments on settling of three different granular samples in varying reduced gravities and examined their packing densities. We used a high precision linear stage to artificially induce reduced gravities inside the zero g environment provided by the ZARM drop tower and observe the settling of our samples. The three samples were fine basalt with particle diameters of 1−200 μm, coarse basalt with 2−5mm and glass beads with 750−1000 μm. The artificial gravities were 150, 250, 500, 750 and 1000mm/s2 and therefore ranged from large asteroid gravity to almost moon gravity. We saw the granular samples have higher volumes in lower gravities and therefore lower packing densities, we also saw the fine basalt be the most sensitive to changes in gravity, up to +19.6 % in volume for 250mm/s2, followed by the coarse basalt particles, up to +12.2 % for 150mm/s2 and the glass beads packing density being the least sensitive to changes in gravity, up to +4.25 % for 250mm/s2. With these experiments we show change in volume is not solely dependent of particle size but also roughness and uniformity, we provide real life experimental data to validate theoretical works and highlight the role of cohesive forces in low gravity environments.
Versions
Related
- Early Planet Formation in Embedded Disks (eDisk). XXV. Inclination-Induced Minor-Axis Brightness Asymmetries Reveal Limited Dust Settling in Embedded Protostellar Disks
- Diverse dust vertical height and settling strength conditions in protoplanetary discs
- A two-stage settling of the Milky Way disk revealed by precise ChronoGal ages
- A Two-stage Settling of the Milky Way Disk Revealed by Precise ChronoGal Ages
- Granular Structure and Local de Broglie Wavelength in Fuzzy Dark Matter Halos
BibTeX
@misc{keulen2026experiments,
title = {{Experiments on Settling of Granular and Cohesive Material in Low Gravity}},
author = {Matthias Keulen and Timo Giese and Kolja Joeris and Jonathan Kollmer},
howpublished = {arXiv},
year = {2026},
month = may,
doi = {10.48550/arxiv.2605.30395},
eprint = {2605.30395},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2605.30395},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Experiments on Settling of Granular and Cohesive Material in Low Gravity
AU - Matthias Keulen
AU - Timo Giese
AU - Kolja Joeris
AU - Jonathan Kollmer
PY - 2026
DA - 2026/05/28
PB - arXiv
DO - 10.48550/arxiv.2605.30395
UR - https://arxiv.org/abs/2605.30395
AB - The regolith of rocky bodies, such as planets or asteroids, generally settles under gravity conditions different from those of Earth. The behavior of granular material is not easily scalable for different gravities. To predict these highly complex systems where cohesive inter particle forces can be comparable to gravitational forces, we need simulations and experiments. We did experiments on settling of three different granular samples in varying reduced gravities and examined their packing densities. We used a high precision linear stage to artificially induce reduced gravities inside the zero g environment provided by the ZARM drop tower and observe the settling of our samples. The three samples were fine basalt with particle diameters of 1−200 μm, coarse basalt with 2−5mm and glass beads with 750−1000 μm. The artificial gravities were 150, 250, 500, 750 and 1000mm/s^2 and therefore ranged from large asteroid gravity to almost moon gravity. We saw the granular samples have higher volumes in lower gravities and therefore lower packing densities, we also saw the fine basalt be the most sensitive to changes in gravity, up to +19.6 % in volume for 250mm/s^2, followed by the coarse basalt particles, up to +12.2 % for 150mm/s^2 and the glass beads packing density being the least sensitive to changes in gravity, up to +4.25 % for 250mm/s^2. With these experiments we show change in volume is not solely dependent of particle size but also roughness and uniformity, we provide real life experimental data to validate theoretical works and highlight the role of cohesive forces in low gravity environments.
ER -