Related papers: Constraints on cometary surface evolution derived …
Reproducing the observed activity of comets with thermophysical models remains a primary challenge of cometary science. We use a pebble-based thermophysical model of gas-pressure build-up in the subsurface to reproduce the global emission…
We present the results of the photometric and spectrophotometric properties of the 67P/Churyumov-Gerasimenko nucleus derived with the OSIRIS instrument during the closest fly-by over the comet, which took place on 14 th February 2015 at a…
We analyse the population of near-Earth Long-Period Comets (LPCs) (perihelion distances q < 1.3 AU and orbital periods P > 10^3 yr). We have considered the sample of LPCs discovered during the period 1900-2009 and their estimated absolute…
We present an updated cumulative size distribution (CSD) for Jupiter Family comet (JFC) nuclei, including a rigourous assessment of the uncertainty on the slope of the CSD. The CSD is expressed as a power law, N(>r_N) \propto r_N^{-q},…
We simulate the stresses induced by temperature changes in a putative hard layer near the surface of comet 67P/Churyumov--Gerasimenko with a thermo-viscoelastic model. Such a layer could be formed by the recondensation or sintering of water…
Explaining the unexpected presence of dune-like patterns at the surface of the comet 67P/Churyumov-Gerasimenko requires conceptual and quantitative advances in the understanding of surface and outgassing processes. We show here that vapor…
The origin of the particular shape of a small body like comet 67P/Churyumov-Gerasimenko (67P/C-G) is a topic of active research. How and when it acquired its peculiar characteristics has distinct implications on the origin of the solar…
We present VLT/MUSE observations of comet 67P/Churyumov-Gerasimenko during its 2021 perihelion passage, from which we generated simultaneous maps of dust, [OI], C$_2$, NH$_2$, and CN comae across 12 pre- and post-perihelion epochs. These…
We summarize the collective knowledge of physical and surface properties of comet nuclei, focusing on those that are obtained from remote observations. We now have measurements or constraints on effective radius for over 200 comets,…
We investigate the ability of a simultaneous fitting of comet 67P/Churyumov-Gerasimenko's non-gravitational forces, torques and total water-outgassing rate, as observed by Rosetta, to constrain complex thermophysical models of cometary…
Context. Breathtaking imagery recorded during the European Space Agency's Rosetta mission confirmed the bilobate nature of comet 67P/Churyumov-Gerasimenko's nucleus. Its peculiar appearance is not unique among comets. The majority of…
(Context) The change of the rotation period and the orientation of the rotation axis of comet 67P/Churyumov-Gerasimenko (67P/C-G) is deducible from images taken by the scientific imaging instruments on-board the Rosetta mission with high…
We use a fully 3-dimensional thermal evolution model to examine the effects of a non-uniform surface albedo on the subsurface thermal structure of comets. Surface albedo markings cast "thermal shadows", with strong lateral thermal…
We here study the level of albedo variegation on the nucleus of Comet 67P/Churyumov-Gerasimenko. This is done by fitting the parameters of a standard photometric phase function model to disk-average radiance factor data in images acquired…
The Rosetta mission delivered images of comet 67P's nucleus at unprecedented resolution which indicate the presence of a global layering system. By merging techniques of structural geology, statistical image processing, and solar system…
The dynamics of a rigid cometary nucleus is described by the evolutions of its center-of-mass and of its rotation state. Solar irradiation that reaches the surface of a cometary nucleus causes the sublimation of volatiles that form the coma…
The European Space Agency Rosetta/Philae mission to Comet 67P/Churyumov-Gerasimenko in 2014-2016 is the most complete and diverse investigation of a comet carried out thus far. Yet, many physical and chemical properties of the comet remain…
The size of large cliff failures may be described in several ways, for instance considering the horizontal eroded area at the cliff top and the maximum local retreat of the coastline. Field studies suggest that, for large failures, the…
Cometary surfaces can change significantly and rapidly due to the sublimation of their volatile material. Many authors have investigated this evolution; Vincent et al. (2017) have used topographic data from all comets visited by spacecrafts…
The Aswan cliff on Comet 67P/Churyumov-Gerasimenko collapsed on 2015 July 10. Thereby, relatively pristine comet material from a depth of ~12 m was exposed at the surface. Observations of the collapse site by the microwave instrument…