Kenneth G. McCracken, AO (born 7 August 1933) is an Australian physicist and leading space scientist, foundation Director of the CSIRO (Commonwealth Scientific and Industrial Research Organisation) Office of Space Science and Applications and Foundation Chief of the CSIRO Division of Mineral Physics. He had earlier worked in the United States of America for several years where he occasionally worked as a consultant for NASA (National Aeronautics and Space Administration). McCracken was the Principal Investigator of an experiment on the Pioneer 7 mission.