 |
| Titel |
An explanation for the bedforms on comet 67P/Churyumov-Gerasimenko |
| VerfasserIn |
Pan Jia, Bruno Andreotti, Philippe Claudin |
| Konferenz |
EGU General Assembly 2016
|
| Medientyp |
Artikel
|
| Sprache |
en
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250129394
|
| Publikation (Nr.) |
 EGU/EGU2016-9501.pdf |
|
|
|
|
|
| Zusammenfassung |
| The recent approach of comet 67P/Churyumov-Gerasimenko by the European Space Agency spacecraft Rosetta has revealed the presence of geomorphologic features at its surface. In particular, surface patterns resembling aeolian ripples or dunes as well as `wind tails' have been observed, especially in the `neck' region. Erosion/deposition processes are unexpected on a comet because of the absence of an atmosphere, that would generate a wind to transport the grains at the surface. However, it is well known that comets experience outgassing when approaching the sun: the solar heat flux induces ice sublimation, generating dust/gas jets, which is at the origin of the comet's coma. Combining a description of sediment transport and hydrodynamics with a thermal model of the comet’s surface and outgassing, we show that, albeit generated by a rarefied atmosphere, these bedforms are paradoxically analogous to ripplemarks emerging on granular beds submitted to viscous shear flows. |
|
|
|
|
|
|