Summary Positions advertised are in various organizations at Johnson Space Center. NASA may fill positions in any of the following series and at any grade level listed in this announcement (GS-0401, GS-1301, GS-1330 at the GS-11/12/13/14/15 levels). Responsibilities Duties described below are at the highest grade advertised. Duties assigned at lower grade levels will be of more limited scope, performed with less independence and limited complexity; duties will be commensurate with the grade of selected employee. Directs technical or scientific efforts across organizational boundaries and provides authoritative guidance to senior officials on highly complex scientific matters. Conducts and oversees advanced technical or scientific research, experiments, analysis, design, test, and evaluation. Applies expert judgment to resolve complex technical or scientific problems and recommends optimal solutions. Advises executive leadership and program managers on complex technical or scientific pr...