The Scientific Importance of Returning Airfall Dust as a Part of Mars Sample Return (MSR)

Abstract

This paper was written by the MSR Science Planning Group 2 (MSPG2) working under a Terms of Reference from NASA and ESA.

Regolith of the Crater Floor Units, Jezero Crater, Mars: Textures, Composition, and Implications for Provenance

“…Future evaluation of potential collecting sites will include estimating the expected size distribution of the regolith grains to ensure that sufficient sample volumes are collected via the regolith sampling bit. Identifying a sampling target with a fine‐grained regolith component like that characterized on the Jezero crater floor, including airfall dust, is of particular interest considering the potential of fine‐grained regolith to provide regional to global insights (e.g., Grady et al., 2022; McLennan et al., 2012). Acquiring a regolith sample that includes contributions from more local components like the coarse‐grained regolith type has the potential to extend understanding of the weathering and erosion histories of the units from which those components are derived.…”

Final Report of the Mars Sample Return Science Planning Group 2 (MSPG2)

“…The overall conclusions of MSPG2 can be summarized with 5 high-level findings: The following section represents a synopsis of 7 reports (Haltigin et al, 2021;Tosca et al, 2021;Velbel et al, 2021;Carrier et al, 2021;Tait et al, 2021;Grady et al, 2021;Swindle et al, 2021) that address the four deliverables (tasks) requested of the MSPG2. This information is offered to ESA and NASA management to aid in securing the approval and resources that would allow the MSR effort to be a success.…”

“…Two planning steps would optimize our ability to take advantage of this opportunity: 1) The dust-covered sample tubes should be loaded into the OS with as little cleaning as possible and 2) The capability to recover the dust early in the workflow within the SRF needs to be established. A further opportunity to advance dust/atmospheric science using MSR, depending on the design of the MSR Campaign elements, may lie in the area of directly sampling and returning airborne dust (Grady et al, 2021).…”

Science and Curation Considerations for the Design of a Mars Sample Return (MSR) Sample Receiving Facility (SRF)

“…Before the sample tubes are opened, a dust removing station will be needed. It will be important to recover all dust from the outside of the sample tubes for further investigation (Grady et al, 2021). It would also be necessary to check the quality of the sample tube seals, make measurements of the sample magnetic properties, and conduct penetrative imaging at this stage.…”

“…There is also a desire to capture the gas behind all gas-tight seals between the spacecraft exterior and the RSTAs (at the time of writing this is expected to be limited to the seal on the PCV). Based on the findings of Grady et al (2021) and extensively commented on by Tait et al (2021), the adventitious dust on the interior surfaces within the PCV that have been exposed to the martian environment is considered to be valuable scientifically, and the SRF needs to include the capability to capture and preserve it. This most directly applies to the outside surfaces of the sample tubes that have been cached on the martian surface.…”