The goal of this project is to demonstrate the use of an innovative source developed at Acree to produce high-quality atomic oxygen (AO) for low Earth orbit (LEO) space effects testing.Space effect testing is conducted in vacuum chambers using oxygen sources to determine the effects of AO on various materials and to develop and test strategies for extending the life of materials in LEO.In order to produce meaningful results, the sources should produce an AO fluence and energy that matches that of LEO. Acrees AO source has been developed over the last ten years and will be demonstrated to meet the AO requirements of this project.Atomic Oxygen,AO,low earth orbit,LEO,Constricted plasma source,Environmental space effects testing.