Results of the ESA study on psychological selection of astronaut applicants for Columbus Missions I: aptitude testing

European participation in the Space Station Freedom brought about new challenges for the psychological selection of astronaut candidates, particularly in respect to specific demands of long duration space flights. For this reason existing selection criteria and methods were reassessed. On these grounds a study was undertaken applying a unique composition of aptitude tests to a group of 97 ESA scientists and engineers who are highly comparable to the expected astronaut applicants with respect to age and education. The tests assessed operational aptitudes such as logical reasoning, memory function, perception, spatial orientation, attention, psychomotor function, and multiple task capacity. The study goals were: 1) Verification of psychometric qualities and applicability of tests in a normative group; 2) Search for culture-fair tests by which multi-national groups can be examined; 3) Identification of test methods which consider general and special operational demands of long duration space flights. Based on the empirical findings a test battery was arranged for use in the selection of ESA astronaut applicants. Results showed that 16 out of the 18 employed tests have good psychometric qualities and differentiate reliably in the special group of testees. The meta structure of the test battery as described by a factorial analysis is presented. Applicability of tests was generally high. Tests were culture-fair, however, a relation between English language skills and test results was identified. Since most item material was language-free, this was explained with the importance of English language skills for the understanding of test instructions. Solutions to this effect are suggested.