The Winchcombe meteorite is a CM chondrite breccia composed of eight distinct lithological units plus a cataclastic matrix. The degree of aqueous alteration varies between intensely altered CM2.0 and moderately altered CM2.6. Although no lithology dominates, three heavily altered rock types (CM2.1-2.3) represent >70 area%. Tochilinite-cronstedtite intergrowths (TCIs) are common in several lithologies. Their compositions can vary significantly, even within a single lithology, which can prevent a clear assessment of alteration extent if only TCI composition is considered. We suggest that this is due to early alteration under localized geochemical microenvironments creating a diversity of compositions and because later reprocessing was incomplete, leaving a record of the parent body's fluid history. In Winchcombe, the fragments of primary accretionary rock are held within a cataclastic matrix (~15 area%). This material is impact-derived fallback debris. Its grain size and texture suggest that the disruption of the original parent asteroid responded by intergranular fracture at grain sizes <100 μm, while larger phases, such as whole chondrules, splintered apart. Reaccretion formed a poorly lithified body. During atmospheric entry, the Winchcombe meteoroid broke apart with new fractures preferentially cutting through the weaker cataclastic

Volatile and organic-rich C-type asteroids may have been one of the main sources of Earth’s water. Our best insight into their chemistry is currently provided by carbonaceous chondritic meteorites, but the meteorite record is biased: only the strongest types survive atmospheric entry and are then modified by interaction with the terrestrial environment. Here we present the results of a detailed bulk and microanalytical study of pristine Ryugu particles, brought to Earth by the Hayabusa2 spacecraft. Ryugu particles display a close compositional match with the chemically unfractionated, but aqueously altered, CI (Ivuna-type) chondrites, which are widely used as a proxy for the bulk Solar System composition. The sample shows an intricate spatial relationship between aliphatic-rich organics and phyllosilicates and indicates maximum temperatures of ~30 °C during aqueous alteration. We find that heavy hydrogen and nitrogen abundances are consistent with an outer Solar System origin. Ryugu particles are the most uncontaminated and unfractionated extraterrestrial materials studied so far, and provide the best available match to the bulk Solar System composition.

Direct links between carbonaceous chondrites and their parent bodies in the solar system are rare. The Winchcombe meteorite is the most accurately recorded carbonaceous chondrite fall. Its pre-atmospheric orbit and cosmic-ray exposure age confirm that it arrived on Earth shortly after ejection from a primitive asteroid. Recovered only hours after falling, the composition of the Winchcombe meteorite is largely unmodified by the terrestrial environment. It contains abundant hydrated silicates formed during fluid-rock reactions, and carbon- and nitrogen-bearing organic matter including soluble protein amino acids. The near-pristine hydrogen isotopic composition of the Winchcombe meteorite is comparable to the terrestrial hydrosphere, providing further evidence that volatile-rich carbonaceous asteroids played an important role in the origin of Earth’s water.

There is believed to be declining interest in cardiothoracic surgical careers among UK medical students. Relative lack of undergraduate exposure to the specialty compared with other surgical specialties may be partly responsible. Using pre- and postintervention analysis, we assessed the ability of a student-led extracurricular engagement event to increase undergraduate interest in the specialty. Fifty-four students attended and 50 (93%) participated in the study. Of the total, 32% of delegates had identified a cardiothoracic mentor, with only 8 and 4% exposed to cardiac and thoracic surgery, respectively, compared with 50% exposed to other surgical specialties. Self-reported understanding of cardiothoracic training increased from 20 to 80% (P < 0.001) after the 1-day event; 77% of delegates reported increased interest in the specialty. We demonstrate that it is possible to provide a free-to-user event that increases engagement using a student-led design. Similar events could increase interest in the specialty and may improve recruitment rates. Current levels of cardiothoracic exposure are very low among UK students.

This paper describes a consumer evaluation that explored the reflections of persons with psychiatric disabilities on receiving individualized feedback following participation in a community research project. Findings indicate that feedback is an important element of research, offering a valued means to reciprocate participants' contributions. Feedback can facilitate mutual learning, fostering hope and empowerment, while participation in performance tests without feedback may reinforce negative self-evaluations. Feedback needs sensitive presentation and discussion, focused on strengths, to be experienced as worthwhile and respectful by people with psychiatric disabilities. This is particularly important as their self-identities may already be undermined by experiences of mental illness. Researchers need dedicated time, resources, and training to incorporate individual feedback in research.