April 9, 2021,
noon - 1 p.m.
APL, Johns Hopkins University &
Observations by the MESSENGER spacecraft led to the discovery of an unusual landform on Mercury, named “hollows”. Hollows are shallow irregular depressions that appear to form by a process of volatile loss, similar to “sublimation degradation” known on icy surfaces. Hollows are a geomorphological manifestation of the unexpectedly high content of moderately volatile elements in Mercury’s crust.