Clues to the Formation of the Moon's Atmosphere
Forskare från Uppsala universitet använde Tandemlaboratoriets instrument för att undersöka proverna från månen. På bilden syns Gyula Nagy, forskare i gruppen för Matrialfysik.
Analysis of Moon dust samples from NASA supported by the Tandem laboratory accelerators reveals that the erosive effect of solar wind ions on the Moon has been greatly overestimated.
The study of the lunar dust has provided valuable data for modelling the origin and formation of the Moon’s thin atmosphere, known as the exosphere. The analysis showed that the erosive impact of solar wind ions has been significantly overestimated. The surface morphology, particularly the roughness and high porosity of lunar dust, has a suppressive effect on erosion.
Chemical Composition Measurements
The Tandem Laboratory contributed to this effort by conducting high-precision measurements of the near-surface chemical composition of authentic lunar samples (Apollo 16 sample 68501). These measurements were combined with erosion rate data and advanced 3D simulations of how Moon dust disperses into the Moon’s outer atmosphere.
Adjusting Exosphere Models
The results are making a substantial contribution to our understanding of how the surfaces of rocky bodies in the solar system are altered.
The data obtained provides experimentally validated estimates of solar sputtering yields and addresses long-standing uncertainties in modelling exospheres.
In particular, two competing processes are considered key drivers of particle ejection into the exosphere: micrometeoroid impact vaporisation and solar wind ion sputtering. Solar wind sputtering was shown to be an order of magnitude lower than previously assumed in exosphere models.
International Collaboration
The study was coordinated by researchers from TU Wien in Austria, in collaboration with researchers from the USA, Switzerland, Germany, and Sweden. Partner institutions included the University of California, University of Virginia, Uppsala University, the Max Planck Institute, and the University of Bern.
Researchers from Uppsala University involved in the project were Gyula Nagy, Eduardo Pitthan, and Daniel Primetzhofer from the Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden.
The Moon’s exosphere
Although not an atmosphere in the conventional sense, the Moon’s atmosphere is referred to as an exosphere. This research offers new insights into how the Moon’s surface gradually “evaporates” under the influence of cosmic radiation and the solar wind, and how exospheres form around rocky bodies elsewhere in the solar system.
Länkar
- Solar wind erosion of lunar regolith is suppressed by surface morphology and regolith properties in Communications Earth & Environment
- Moon under bombardment by TU Wien