DENDRITIC MICROSTRUCTURES FORMED DURING SOLIDIFICATION PROCESSING (SUCH AS CASTING WELDING AND BRAZING) DETERMINE THE PROPERTIES OF STRUCTURAL METALLIC ALLOYS USED IN AEROSPACE MATERIALS ESSENTIAL FOR NASA EXPLORATION IN SPACE AND PRODUCED IN NUMEROUS US INDUSTRIES WITH COMMERCIAL APPLICATIONS RANGING FROM AUTOMOBILE ENGINE PARTS TO TURBINE BLADES USED IN AIRCRAFT AND POWER GENERATION. THIS PROJECT IS AIMED AT THE DEVELOPMENT OF MULTISCALE AND MULTIPHYSICS COMPUTATIONAL MODELS TO RELATE SOLIDIFICATION PROCESSING CONDITIONS WITH ALLOY MICROSTRUCTURES AND PROPERTIES. THOSE MODELS PROVIDE ENHANCED CAPABILITIES TO ACCELERATE THE DEVELOPMENT OF ADVANCED (LIGHTWEIGHT HIGH-TEMPERATURE AND EXTREME ENVIRONMENT) AEROSPACE MATERIALS PRODUCED ON GROUND ENABLING RELIABLE PREDICTIONS OF MICROSTRUCTURES FORMED BY CONVENTIONAL AND NEW MATERIALS SYNTHESIS METHODS SUCH AS 3D PRINTING AND ADDITIVE MANUFACTURING. IN ADDITION THEY PROVIDE SUPPORT FOR MATERIALS PROCESSING ON EXTRATERRESTRIAL SURFACES IN A REDUCED GRAVITY ENVIRONMENT. MODEL DEVELOPMENT IS CARRIED OUT ITERATIVELY WITH MICROGRAVITY SOLIDIFICATION EXPERIMENTS CARRIED OUT IN THE MATERIALS SCIENCE LABORATORY AND TRANSPARENT ALLOY AND DECLIC FACILITIES ABOARD THE INTERNATIONAL SPACE STATION (ISS) IN COLLABORATION WITH ESA AND CNES RESEARCH TEAMS.