Pinnacles on the 67P comet nucleus: Evidence for large scale erosion and hierarchical agglomeration of the nucleus

The observed characteristics of pinnacles found on 67P agree with the suggestion that they are erosion remnants formed due to a slowdown of erosion in places where nucleus material is more resistant to sublimational erosion than the material around it. In this case the maximum heights of pinnacles (100-200 m) gives a lower boundary for the amount of surface material lost and their diameters (typically tens of meters) are a measure of the size of the erosion-resistant parts.