Related papers: A fully 3-dimensional thermal model of a comet nuc…
We here study the transfer process of material from one hemisphere to the other (deposition of airfall material) on an active comet nucleus, specifically 67P/Churyumov-Gerasimenko. Our goals are to: 1) quantify the thickness of the airfall…
The physical properties of cometary nuclei observed today relate to their complex history and help to constrain their formation and evolution. In this article, we review some of the main physical properties of cometary nuclei and focus in…
There are many factors that contribute to the breaking of the spherical symmetry of a neutron star. Most notably is rotation, magnetic fields, and/or accretion of matter from companion stars. All these phenomena influence the macroscopic…
The OSIRIS/NAC camera onboard the Rosetta spacecraft acquired approximately 27000 images of comet 67PChuryumov-Gerasimenko at spatial scales down to a few centimeters. Numerous sequences of images separated by a few minutes suitable to…
Cometary activity is a compelling subject of study, with thermophysical models playing a pivotal role in its understanding. However, traditional numerical solutions for small body thermophysical models are computationally intensive, posing…
We investigate the thermal evolution of 3I/ATLAS, the third macroscopic interstellar object discovered on 2025 July 1. By comparing modeled thermal profiles with observations of volatile activity, it is possible to constrain bulk physical…
The first computational model of solid-phase chemistry in cometary nuclear ices is presented. An astrochemical kinetics model, MAGICKAL, is adapted to trace the chemical evolution in multiple layers of cometary ice, over a representative…
Comets display with decreasing solar distance an increased emission of gas and dust particles, leading to the formation of the coma and tail. Spacecraft missions provide insight in the temporal and spatial variations of the dust and gas…
We extend an existing thermophysical activity model of comet 67P/Churyumov-Gerasimenko to include pressure buildup inside the pebbles making up the nucleus. We test various quantities of H$_{2}$O and CO$_{2}$, in order to simulate the…
The Rosetta mission of the European Space Agency has been orbiting the comet 67P/Churyumov-Gerasimenko (67P) since August 2014 and is now in its escort phase. A large complement of scientific experiments designed to complete the most…
Thermal annealing of interstellar ices takes place in several stages of star formation. Knowledge of this process comes from a combination of astronomical observations and laboratory simulations under astrophysically relevant conditions.…
We investigate the thermal evolution of comet 67P/Churyumov-Gerasimenko's subsurface in the Seth_01 region, where active pits have been observed by the ESA/Rosetta mission. Our simulations show that clathrate destabilization and amorphous…
We analyze the physical properties and dynamical origin of a curved jet of comet 67P/Churyumov-Gerasimenko that was observed repeatedly in several nucleus rotations starting on May 30 and persisting until early August, 2015. We simulated…
(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…
On November 12, 2014, the ESA/Rosetta descent module Philae landed on the Abydos site of comet 67P/Churyumov-Gerasimenko. Aboard this module, the Ptolemy mass spectrometer measured a CO/CO2 ratio of 0.07 +/- 0.04 which differs substantially…
The Rosetta mission provided us with detailed data of the surface of the nucleus of comet 67P/Churyumov-Gerasimenko.In order to better understand the physical processes associated with the comet activity and the surface evolution of its…
We collect observational evidence that supports the scheme of mass transfer on the nucleus of comet 67P/Churyumov-Gerasimenko. The obliquity of the rotation axis of 67P causes strong seasonal variations. During perihelion the southern…
The chemical composition of comets is frequently assumed to be directly provided by the observations of the abundances of volatile molecules in the coma. The present work aims to determine the relationship between the chemical composition…
The trajectories of dust particles ejected from a comet are affected by solar radiation pressure as a function of their ratios of radiation pressure cross section to mass. Therefore, a study on the orbital evolution of the particles caused…
We present the results of a series of calculations studying the collapse of molecular cloud cores performed using a three-dimensional smoothed particle hydr odynamics code with radiative transfer in the flux-limited diffusion approximation.…