Fractures on comet 67P/Churyumov-Gerasimenko observed by Rosetta/OSIRIS
2015 (English)In: Geophysical Research Letters, ISSN 0094-8276, Vol. 42, no 13, 5170-5178 p.Article in journal (Refereed) Published
The Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS) experiment onboard the Rosetta spacecraft currently orbiting comet 67P/Churyumov-Gerasimenko has yielded unprecedented views of a comet's nucleus. We present here the first ever observations of meter-scale fractures on the surface of a comet. Some of these fractures form polygonal networks. We present an initial assessment of their morphology, topology, and regional distribution. Fractures are ubiquitous on the surface of the comet's nucleus. Furthermore, they occur in various settings and show different topologies suggesting numerous formation mechanisms, which include thermal insulation weathering, orbital-induced stresses, and possibly seasonal thermal contraction. However, we conclude that thermal insolation weathering is responsible for creating most of the observed fractures based on their morphology and setting in addition to thermal models that indicate diurnal temperature ranges exceeding 200K and thermal gradients of similar to 15K/min at perihelion are possible. Finally, we suggest that fractures could be a facilitator in surface evolution and long-term erosion.
Place, publisher, year, edition, pages
2015. Vol. 42, no 13, 5170-5178 p.
comets, fractures, Rosetta, OSIRIS, Comet 67P
Astronomy, Astrophysics and Cosmology
IdentifiersURN: urn:nbn:se:uu:diva-260861DOI: 10.1002/2015GL064500ISI: 000358691300012OAI: oai:DiVA.org:uu-260861DiVA: diva2:848786
FunderSwedish National Space Board