Sealed Planetary Return Canister (SPRC)

Sample return missions have primary importance in future planetary missions. A basic requirement is that samples be returned in pristine, uncontaminated condition, necessitating development of a canister system capable of maintaining cleanliness and seal integrity through a variety of environments. Further development of the Sealed Planetary Return Canister (SPRC), is proposed after a successful Phase 1 program. Besides providing a high integrity seal, the canister incorporates features for robotic manipulation and to allow the sample to be accessed in a controlled manner upon return to Earth. The SPRC seal system addresses the two most significant concerns for planetary samples?seal surfaces contaminated by the sample and high pressure due to the phase change of volatiles. The SPRC incorporates a novel sealing system evolved from the only marginally successful Apollo indium knife edge seal approach but with added features to address the difficulties and inconsistencies observed. The indium is contained within a protective barrier to prevent against contamination, and the knife edge is mechanically cleaned during the sealing process. The container body can be configured to accommodate a variety of samples including rock cores, rock fragments, regolith, dust, and frozen soil. Atmospheric samples can also be preserved. The design is readily scalable and adaptable to specific missions. The prototype developed in Phase 1 demonstrated a leakage rate of less than 1e-6 cc-atm/s, meeting the primary science requirement.