  In recent years, the gravitational collapse of pebble clumps in the early
Solar System has been regarded as a plausible scenario for the origin of
comets. In this context, ``pebbles'' represent mm- to cm-sized dust aggregates
composed of (sub)micron-sized dust particles, and the structure of km-sized
comets is thought to be an agglomerate of pebbles. The contact radius for
pebble-pebble contacts was modelled in an earlier study; however, the pressure
dependence of the interpebble contact radius was not considered. Here, we
revisit the interpebble contact radius in a comet nucleus. We calculated the
interpebble contact radius based on JKR contact theory, and we took into
consideration the effect of lithostatic pressure. We found that the interpebble
contact radius varies with depth from the surface, and the earlier model
underestimated it by one order of magnitude at the centre of the comet nucleus.
