Human-assisted Mars Sample Return

Any Mars Sample Return campaign must assure a very low probability of inadvertent release of Mars material into the Earth's biosphere in order to provide protection against the extremely unlikely possibility of biological hazards in the returned material. Containment assurance requires breaking the chain of contact with Mars: any Mars material reaching Earth must be inside a sealed sample container. Then the integrity of the sample container must be maintained (with an unprecedented degree of confidence) until delivered to a secure receiving facility on Earth. Earth entry poses a challenge to sample container integrity. In most studies this challenge is met by developing a new, highly-robust, robotic Earth entry vehicle; but NASA's plans for future human space activities offer other possibilities. These plans for the next couple of decades include options for crewed operations in lunar and Mars orbits. This paper describes the results of a study of options for having robotic spacecraft deliver samples to these locations for handoff to the crewed vehicle followed by return to Earth with the crew. Conceptual designs for several options are presented and pros and cons relative to the completely robotic campaign are discussed.