THE RESEARCH ACTIVITIES OUTLINED IN THIS PROPOSAL CENTER ON THE DEVELOPMENT OF NEW CAPABILITIES FOR BALLOON-BORNE ASTRONOMICAL OBSERVATIONS. THIS SCIENTIFIC PROJECT IS THE BALLOON EXPERIMENTAL TWIN TELESCOPE FOR INFRARED INTERFEROMETRY (BETTII). THESE ACTIVITIES WILL BE PERFORMED BY ONE RESEARCH ASSISTANT AT CUA UNDER THE DIRECTION OF THE CUA PRINCIPAL INVESTIGATOR IN CLOSE PARTNERSHIP WITH NASA SCIENTISTS.