Fig. 19

image

Fluid threshold velocity calculated using the Shao-Lu formulation with values for gravity appropriate for 67P (g = 1.55 × 10-4 m s-2). The velocity rises rapidly as the particle size decreases because of cohesive forces. Gas pressures of 0.003 Pa (solid line) and 0.03 Pa (dashed line) are shown.

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.