On the formation of the lunar herringbone pattern

The V-shaped ridge components of the lunar herringbone pattern are simulated by simultaneous and nearly simultaneous impact cratering in the laboratory. The results of the simulations, together with a mathematical model developed for the case of simultaneous impacts, indicate that the pattern resulted from simultaneous impact formation of adjacent secondary craters. In addition, preliminary experimental results suggest that many secondaries of the crater Copernicus were produced by fragments that impacted either simultaneously or nearly simultaneously with the uprange fragments impacting first, at angles greater than 60 deg measured from the normal to the surface.