Much has been learned about Mars through data returned from space missions and analyses of martian meteorites. There are, however, many questions still outstanding which cannot currently be answered—including the issue of whether there is, or was, life on Mars. The return of a cache of samples—including of the atmosphere—from separate locations in Jezero Crater and with differing petrogeneses will provide the international community with the opportunity to explore part of the evolutionary history of Mars in great detail. Specifically, measurements of the isotopic compositions of the light elements H, C, N, O, Cl, and S can be used to follow how volatile species cycle through the different martian volatile reservoirs (atmosphere, lithosphere, cryosphere, and hydrosphere). Measurement of isotopic fractionation enables inference of the environmental conditions (e.g., temperature, water/rock ratio) under which fractionation occurred. Knowing the contextual relationship of the materials to their geological settings, coupled with precise compositional measurements will enable a more thorough understanding of martian volatile history and allow a picture to be constructed of water and climate on Mars as represented at Jezero Crater.

It is hypothesized that the Solar System was once populated by Moon to Mars-sized planetary embryos, however, resulting debris from their disruptions is not easily discernible in the modern-day Solar System. Angrites are among the oldest differentiated materials in our Solar System, recording prolonged magmatism, and their parent body is expected to have been Moon to Mars-sized. Even so, no parent body in the modern-day Solar System has been identified. Our UV-Vis-NIR spectra of ten angrites, compared with 712 asteroids, reveal multiple candidates with spectral similarities through curve matching and band-structure analysis. Asteroid (246) Asporina provides the best analog for the angrite meteorites, potentially representing a fragment of a long-lost Moon to Mars-sized body that once resided in the inner Solar System, which was subsequently incorporated into the growing terrestrial planets.

The Hayabusa2 spacecraft brought samples to Earth from asteroid (162173) Ryugu in December 2020. Here we review the main characteristics of the Hayabusa2 mission, with a particular focus on sample collection and return. After describing how the material was collected and subsequently curated, we outline some of the major findings from the mission so far, including the nature of the organic materials and the age, duration, extent and temperature of the aqueous alteration experienced by the Ryugu materials. We discuss the implications of these observations for the composition of early Solar System materials and the processes that they have experienced. Finally, we consider the results in the context of forthcoming sample return missions and what may be learnt from them. This Perspective follows the journey of the sample returned from asteroid Ryugu by the Hayabusa2 spacecraft from collection to curation and presents the main results from its analysis so far. The piece highlights the implications for our knowledge of early Solar System processes and lessons for future sample return missions.

The Winchcombe meteorite fell on February 28, 2021 in Gloucestershire, United Kingdom. As the most accurately recorded carbonaceous chondrite fall, the Winchcombe meteorite represents an opportunity to link a tangible sample of known chemical constitution to a specific region of the solar system whose chemistry can only be otherwise predicted or observed remotely. Winchcombe is a CM carbonaceous chondrite, a group known for their rich and varied abiotic organic chemistry. The rapid collection of Winchcombe provides an opportunity to study a relatively terrestrial contaminant‐limited meteoritic organic assemblage. The majority of the organic matter in CM chondrites is macromolecular in nature and we have performed nondestructive and destructive analyses of Winchcombe by Raman spectroscopy, online pyrolysis–gas chromatography–mass spectrometry (pyrolysis–GC–MS), and stepped combustion. The Winchcombe pyrolysis products were consistent with a CM chondrite, namely aromatic and polycyclic aromatic hydrocarbons, sulfur‐containing units including thiophenes, oxygen‐containing units such as phenols and furans, and nitrogen‐containing units such as pyridine; many substituted/alkylated forms of these units were also present. The presence of phenols in the online pyrolysis products indicated only limited influence from aqueous alteration, which can deplete the phenol precursors in the macromolecule when aqueous alteration is extensive. Raman spectroscopy and stepped combustion also generated responses consistent with a CM chondrite. The pyrolysis–GC–MS data are likely to reflect the more labile and thermally sensitive portions of the macromolecular materials while the Raman and stepped combustion data will also reflect the more refractory and nonpyrolyzable component; hence, we accessed the complete macromolecular fraction of the recently fallen Winchcombe meteorite and revealed a chemical constitution that is similar to other meteorites of the CM group.

Two bulk Winchcombe along with six other CM2 meteorite samples were subjected to quantitative evolved gas analysis. The observed release patterns for almost all volatile species demonstrate close similarity for all the samples and especially between those for Winchcombe. This can be considered as a fingerprint for this petrological type of meteorites. We identified several gases including H-2, H2O, O-2, CO, CO2, and SO2 released in different temperature ranges. The sources and mechanisms of their release were also established. Some of the gases, H-2, CO, and CO2, are released as a result of oxidation of macromolecular organic material from oxygen derived from oxygen-bearing minerals (a part of CO2 is also released as a result of decomposition of carbonates). The others, O-2 and H2O, are associated with the phase transformation/decomposition of phyllosilicates and (oxy)hydrates, while a high-temperature release of SO2 is associated mostly with the decomposition of sulfides and in few cases also with sulfates. A low-temperature release of SO2 is due to evaporation and oxidation of elemental sulfur from the meteoritic matrix and organic material. The total concentrations of H (mostly represented by H2O), C, and S, calculated according to calibration of the quadrupole mass spectrometer with reference gases and decomposition of solid samples (CaSO4 center dot 2H(2)O and NaHCO3) are in reasonable agreement with those determined by independent methods. Variations in the ratio of the carbon amounts released as CO2 and CO (CCO2$$ {\mathrm{C}}_{{\mathrm{C}\mathrm{O}}_2} $$/C-CO) between the samples could be an indicator of their terrestrial weathering.

Meteoritics & Planetary ScienceEarly View Award Meteoritical Society Service Award citation for Richard C. Greenwood Devin L. Schrader, Corresponding Author Devin L. Schrader [email protected] orcid.org/0000-0001-5282-232X Buseck Center for Meteorite Studies, School of Earth and Space Exploration, Arizona State University, Tempe, Arizona, USASearch for more papers by this authorJemma Davidson, Jemma Davidson orcid.org/0000-0002-3725-2960 Astromaterials Research and Exploration Science (ARES) Division, XI2, NASA Johnson Space Center, Houston, Texas, USASearch for more papers by this authorConel M. O'D Alexander, Conel M. O'D Alexander orcid.org/0000-0002-8558-1427 Earth and Planets Laboratory, Carnegie Institution for Science, Washington, DC, USASearch for more papers by this authorMartin R. Lee, Martin R. Lee orcid.org/0000-0002-6004-3622 School of Geographical and Earth Sciences, University of Glasgow, Glasgow, UKSearch for more papers by this authorMonica M. Grady, Monica M. Grady orcid.org/0000-0002-4055-533X School of Physical Sciences, The Open University, Milton Keynes, UKSearch for more papers by this author Devin L. Schrader, Corresponding Author Devin L. Schrader [email protected] orcid.org/0000-0001-5282-232X Buseck Center for Meteorite Studies, School of Earth and Space Exploration, Arizona State University, Tempe, Arizona, USASearch for more papers by this authorJemma Davidson, Jemma Davidson orcid.org/0000-0002-3725-2960 Astromaterials Research and Exploration Science (ARES) Division, XI2, NASA Johnson Space Center, Houston, Texas, USASearch for more papers by this authorConel M. O'D Alexander, Conel M. O'D Alexander orcid.org/0000-0002-8558-1427 Earth and Planets Laboratory, Carnegie Institution for Science, Washington, DC, USASearch for more papers by this authorMartin R. Lee, Martin R. Lee orcid.org/0000-0002-6004-3622 School of Geographical and Earth Sciences, University of Glasgow, Glasgow, UKSearch for more papers by this authorMonica M. Grady, Monica M. Grady orcid.org/0000-0002-4055-533X School of Physical Sciences, The Open University, Milton Keynes, UKSearch for more papers by this author First published: 25 June 2024 https://doi.org/10.1111/maps.14231 Editorial Handling—Dr. Agnieszka P Baier Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Early ViewOnline Version of Record before inclusion in an issue RelatedInformation

Ryugu is the C-type asteroid from which material was brought to Earth by the Hayabusa2 mission. A number of individual grains and fine-grained samples analysed so far for noble gases have indicated that solar wind and planetary (known as P1) noble gases are present in Ryugu samples with concentrations higher than those observed in CIs, suggesting the former to be more primitive compared to the latter. Here we present results of analyses of three fine-grained samples from Ryugu, in one of which Xe concentration is an order of magnitude higher than determined so far in other samples from Ryugu. Isotopically, this Xe resembles P1, but with a much stronger isotopic fractionation relative to solar wind and significantly lower 36Ar/132Xe ratio than in P1. This previously unknown primordial noble gas component (here termed P7) provides clues to constrain how the solar composition was fractionated to form the planetary components. Ryugu is more primitive than carbonaceous chondrites, according to elevated noble gas concentrations. Elevated Xe and its isotopic composition further provide constraints on fractionation of the solar composition to form the early planetary components.

Ryugu is the C-type asteroid from which material was brought to Earth by the Hayabusa2 mission. A number of individual grains and fine-grained samples analysed so far for noble gases have indicated that solar wind and planetary (P1=Q) noble gases are present in Ryugu samples with concentrations higher than those observed in CIs, suggesting the former to be more primitive compared to the latter. We analysed three fine-grained samples from Ryugu, one of which contained a Xe concentration an order of magnitude higher (4x10 -7 cc STP/g) than previously found in samples from Ryugu. Isotopically, this Xe resembles Q, but with a much stronger (by a factor of four) isotopic fractionation relative to solar wind and an 36 Ar/ 132 Xe ratio at least an order of magnitude lower than in P1. This new planetary primordial noble gas component (here termed P7) provides clues to constrain how the solar composition was fractionated to form the planetary components.

Dust transported in the martian atmosphere is of intrinsic scientific interest and has relevance for the planning of human missions in the future. The MSR Campaign, as currently designed, presents an important opportunity to return serendipitous, airfall dust. The tubes containing samples collected by the Perseverance rover would be placed in cache depots on the martian surface perhaps as early as 2023-24 for recovery by a subsequent mission no earlier than 2028-29, and possibly as late as 2030-31. Thus, the sample tube surfaces could passively collect dust for multiple years. This dust is deemed to be exceptionally valuable as it would inform our knowledge and understanding of Mars' global mineralogy, surface processes, surface-atmosphere interactions, and atmospheric circulation. Preliminary calculations suggest that the total mass of such dust on a full set of tubes could be as much as 100 mg and, therefore, sufficient for many types of laboratory analyses. Two planning steps would optimize our ability to take advantage of this opportunity: (1) the dust-covered sample tubes should be loaded into the Orbiting Sample container (OS) with minimal cleaning and (2) the capability to recover this dust early in the workflow within an MSR Sample Receiving Facility (SRF) would need to be established. A further opportunity to advance dust/atmospheric science using MSR, depending upon the design of the MSR Campaign elements, may lie with direct sampling and the return of airborne dust.

Samples returned from Mars would be placed under quarantine at a Sample Receiving Facility (SRF) until they are considered safe to release to other laboratories for further study. The process of determining whether samples are safe for release, which may involve detailed analysis and/or sterilization, is expected to take several months. However, the process of breaking the sample tube seal and extracting the headspace gas will perturb local equilibrium conditions between gas and rock and set in motion irreversible processes that proceed as a function of time. Unless these time-sensitive processes are understood, planned for, and/or monitored during the quarantine period, scientific information expected from further analysis may be lost forever. At least four processes underpin the time-sensitivity of Mars returned sample science: (1) degradation of organic material of potential biological origin, (2) modification of sample headspace gas composition, (3) mineral-volatile exchange, and (4) oxidation/reduction of redox-sensitive materials. Available constraints on the timescales associated with these processes supports the conclusion that an SRF must have the capability to characterize attributes such as sample tube headspace gas composition, organic material of potential biological origin, as well as volatiles and their solid-phase hosts. Because most time-sensitive investigations are also sensitive to sterilization, these must be completed inside the SRF and on timescales of several months or less. To that end, we detail recommendations for how sample preparation and analysis could complete these investigations as efficiently as possible within an SRF. Finally, because constraints on characteristic timescales that define time-sensitivity for some processes are uncertain, future work should focus on: (1) quantifying the timescales of volatile exchange for core material physically and mineralogically similar to samples expected to be returned from Mars, and (2) identifying and developing stabilization or temporary storage strategies that mitigate volatile exchange until analysis can be completed.

The Mars Sample Return (MSR) Campaign must meet a series of scientific and technical achievements to be successful. While the respective engineering responsibilities to retrieve the samples have been formalized through a Memorandum of Understanding between ESA and NASA, the roles and responsibilities of the scientific elements have yet to be fully defined. In April 2020, ESA and NASA jointly chartered the MSR Science Planning Group 2 (MSPG2) to build upon previous planning efforts in defining 1) an end-to-end MSR Science Program and 2) needed functionalities and design requirements for an MSR Sample Receiving Facility (SRF). The challenges for the first samples brought from another planet include not only maintaining and providing samples in pristine condition for study, but also maintaining biological containment until the samples meet sample safety criteria for distribution outside of biocontainment. The MSPG2 produced six reports outlining 66 findings. Abbreviated versions of the five additional high-level MSPG2 summary findings are: Summary-1. A long-term NASA/ESA MSR Science Program, along with the necessary funding and human resources, will be required to accomplish the end-to-end scientific objectives of MSR. Summary-2. MSR curation will need to be done concurrently with Biosafety Level-4 containment. This would lead to complex first-of-a-kind curation implementations and require further technology development. Summary-3. Most aspects of MSR sample science can, and should, be performed on samples deemed safe in laboratories outside of the SRF. However, other aspects of MSR sample science are both time-sensitive and sterilization-sensitive and would need to be carried out in the SRF. Summary-4. To meet the unique science, curation, and planetary protection needs of MSR, substantial analytical and sample management capabilities would be required in an SRF. Summary-5. Because of the long lead-time for SRF design, construction, and certification, it is important that preparations begin immediately, even if there is delay in the return of samples.