Descent-speed testing of a hazard detection system for safe landing on MarsIn a previous paper we described an approach for testing a prototype system designed to detect hazards during the terminal descent phase of a mission to Mars. The system under development at the Jet Propulsion Laboratory (JPL) utilizes a scanning laser radar and an inertial measurement unit to map the landing zone, identify hazards, and thenguide the vehicle to a safe landing site. The test approach consisted of a placing this system on a rocket sled, accelerating the sled to typical descent speeds, and mapping a simulated Martian terrain. The data would then be processed to identify hazards and locate a safe landing site. Since ref. 1 was written several such tests have been performed. In this paper we provide an update on the testing methodology and we present preliminary results from one of the tests.