ENTRY, DESCENT, AND LANDING (EDL) ARE AMONG THE MOST CRITICAL PHASES FOR A PLANETARY MISSION. A CREWED MARS MISSION WILL REQUIRE A LANDING PRECISION THAT IS TWO ORDERS OF MAGNITUDE HIGHER THAN THE BEST PRECISION EVER ACHIEVED IN ROBOTIC MISSIONS THUS FAR. THE REQUIREMENT TO LAND A SIGNIFICANTLY HEAVIER MASS FOR A HUMAN MISSION BY ALL-PROPULSIVE SYSTEM ALSO PUTS MUCH GREATER PREMIUM ON REDUCING THE PROPELLANT CONSUMPTION DURING THE POWERED DESCENT AND LANDING. LANDING HUMAN ON THE MOON AND RETURNING TO EARTH IN A SAFER, MORE FLEXIBLE AND ACCURATE FASHION THAN IN THE APOLLO ERA IS MADE FEASIBLE WITH ADVANCED EDL GUIDANCE, NAVIGATION, AND CONTROL TECHNOLOGIES. FOR A HUMAN MARS MISSION, AEROCAPTURE IS AN ENABLING TECHNOLOGY THAT CAN PLACE THE ARRIVING SPACECRAFT IN A MARTIAN ORBIT WITH LITTLE PROPELLANT USAGE. TO ACHIEVE THE HIGH PRECISION FOR ENSURED MISSION SUCCESS WHILE REQUIRING THE LEAST AMOUNT OF PROPELLANT, THE GUIDANCE ALGORITHMS MUST BE ROBUST, ACCURATE, AND OPTIMAL. UNLIKE THE TRADITIONAL DIVIDE-AND-CONQUER APPROACH IN GUIDANCE ANALYSIS AND DESIGN, THE ENTRY AND POWERED DESCENT GUIDANCE NEEDS TO WORK TOGETHER TO DETERMINE THE BEST ENTRY CONDITION, ENTRY TRAJECTORY AND POWERED DESCENT AND LANDING MANEUVERS TO MAXIMIZE THE PERFORMANCE AND PRECISION IN ALL POSSIBLE SCENARIOS. IN ADDITION, RECENT STUDIES HAVE BROUGHT THE POSSIBILITY THAT NON-TRADITIONAL AEROCAPTURE AND ENTRY FLIGHT WITH THE SO-CALLED DIRECT FORCE CONTROL APPROACH MAY YIELD BENEFITS OVER THE TRADITIONAL BANK-ANGLE-ONLY AEROASSIST FLIGHT IN CERTAIN CASES. THIS PROJECT CONSISTS OF A SERIES OF TASKS THAT AIM AT DEVELOPING, MATURING AND INCREASING THE TRL LEVELS OF THE ADVANCED AEROASSIST AND POWERED GUIDANCE ALGORITHMS INCLUDING AEROCAPTURE, ENTRY, POWERED DESCENT, AND PLANETARY ASCENT GUIDANCE ALGORITHMS, INFUSING AND ASSISTING THE IMPLEMENTATION OF THESE ALGORITHMS AT NASA JOHNSON SPACE CENTER, AND INVESTIGATING AND EVALUATING ALTERNATIVE NEW APPROACHES AND CONCEPTS WITH THESE TOOLS. THE PROJECT WILL INVOLVE CLOSE COLLABORATION WITH NASA ENGINEERS AT JOHNSON SPACE CENTER.