Rock Size?Frequency Distributions at the InSight Landing Site, Mars

Rocks around the InSight lander were measured in orthoimages of near field (<10 m), panoramas far (<40 and a high-resolution orbital image (1 km2). The cumulative fractional area versus diameter size-frequency distributions for four areas fall on exponential model curves used estimating hazards landing spacecraft. rock abundance varies from 0.6% sand pebble-rich to east within Homestead hollow ?3–5% progressively rockier south, north, west. entire is just over 3%, which falls between that at Phoenix (2%) Spirit (5%) sites. m) could be identified both surface panorama same curve as average near-field rocks. (27.5 cm/pixel) ?500 m includes several rocky ejecta craters 4–5% curves, similar northern western areas. As result, abundances observed orbit those viewed surface. These measurements are consistent with thermal imaging estimates larger pixel well expectations fragmentation theory an impacted Amazonian/Hesperian lava flow.