Overview of the Phoenix Entry, Descent, and Landing System Architecture

NASA’s Mars Phoenix Lander began its journey to Mars from Cape Canaveral, Florida in August 2007, but its journey to the launch pad beganmany years earlier in 1997 as NASA’sMars Surveyor Program 2001Lander. In the intervening years, the entry, descent, and landing system architecture went through a series of changes, resulting in the system that flew to the surface of Mars on 25 May 2008. Some changes, such as entry velocity and landing site elevation, were the result of differences in mission design. Other changes, including the removal of hypersonic guidance, the reformulation of the parachute deployment algorithm, and the addition of the backshell avoidance maneuver, were driven by constant efforts to augment system robustness. An overview of the Phoenix entry, descent, and landing system architecture is presented along with rationales driving the entry, descent, and landing system design choices. These design choices resulted in the robust Phoenix landing system that successfully landed onMars on 25 May 2008.