Abstract: Polymers and other oxidizable materials on the exterior of spacecraft in the low Earth orbit (LEO) space environment can be eroded due to reaction with atomic oxygen (AO). Therefore, in order to design durable spacecraft, it is important to know the LEO AO erosion yield (Ey, volume loss per incident oxygen atom) of materials susceptible to AO reaction. The Polymers Experiment was developed to determine the AO Ey of various polymers and other materials flown in ram and wake orientations in LEO…