The primordial disc of small icy planetesimals, once located at 15–from the Sun, was
disrupted by giant planet migration in the early Solar system. The primordial disc thereby …

Although comets have been observed and studied since antiquity, the comet nucleus is a
much more recent concept:" It has been stated that within the head of a comet there is …

Kuiper belt objects, such as Arrokoth, the probable progenitors of short-period comets,
formed and evolved at large heliocentric distances, where the ambient temperatures appear …

Solar system bodies with surface and subsurface volatiles will show observational evidence
of activity when they reach a temperature where those volatiles change from solid to gas and …

As the spin axis of comet 67P/Churyumov–Gerasimenko (67P) is not normal to the orbital
plane, 67P has strong seasonal changes in the illumination conditions on the nucleus' …

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 …

A numerical code is developed for evolutionary calculations of the thermal structure and
composition of a porous comet nucleus made of water ice, in amorphous or crystalline form …

Taking into account the low values of average density reported for Comet P/Halley, a model
of a porous comet nucleus has been developed. The model includes heat conduction …

Laboratory comet simulation experiments are discussed in the context of theoretical models
and recent ground‐based and spacecraft observations, especially the Giotto observations of …

Several classes of chondritic meteorites experienced heterogeneous aqueous alteration
and subsequent brecciation before agglomeration into the final parent bodies. These …