Fig. 4: 2D Numerical simulation of the Dawes crater formation.
From: Lunar samples record an impact 4.2 billion years ago that may have formed the Serenitatis Basin
Snapshots are taken during the early crater excavation phase (20 s after impact) that includes the ejecta creation. The black line separates the 300-m-thick mare basalt layer from the underlying crust. The material plot (a) indicates some material was excavated deeper than the mare layer at this time. The temperature plot (b) shows that all ejecta composed of the underlying crust layer experienced T < 1000 K at this time. Velocity plot (c) shows the vertical component of velocity vector (y), indicating that the bulk of the ejecta is moving at <600 m/s, with the maximum at ~1000 m/s. Safe estimate suggest about 20% of the ejecta coming from the underlying crust to have sufficient launch speeds to reach the landing site.
