Carbon in CI chondrites: A comparison to asteroid sample returns
Lead Supervisor: Dr Queenie Chan and Prof. Sara Russell
Location: Royal Holloway University of London, Earth Sciences (in collaboration with Natural History Museum)
Duration: 6 weeks
Suitable undergraduate degrees: Chemistry; Geology; Planetary Science; Earth Sciences
Project background
The return of material from carbon rich asteroids Bennu and Ryugu has reignited our interest in aqueously altered carbonaceous chondrites. We propose to study the CI (Ivuna-type) chondrites to enable better comparisons with current and recent work on these two asteroid sample returns, focusing on better understanding their carbonaceous components and their spatial distribution in asteroidal material.
Bennu is one of the most carbon rich of all astromaterials, containing discrete carbonaceous phases up to tens of microns across (Foustoukos et al., 2024; Clementt et al., 2024). Their closest meteoritic analogues are the carbonaceous CI chondrites, and so we propose to take a relook at these rare samples and study their carbonaceous components using similar techniques that are being applied to asteroid sample return.
Our work on the recent Winchcombe (CM2) meteorite fall showed that this meteorite contains discrete carbon and nitrogen rich components (King et al. 2022); here a similar experimental set up will be used, in addition to spectral analysis, to better characterise carbon rich components in CI chondrites.
Overall, our aims are to (1) characterize carbon bearing components in the CI chondrite Ivuna using multiple techniques; (2) compare data to that obtained from Ryugu and Bennu, and provide a baseline for comparison, as well as developing protocols that we can apply to the analysis of sample return material in the future; (3) train a student in these techniques.
We propose to image and characterise carbonaceous material from the Ivuna meteorite, the most recent and uncontaminated sizable CI meteorite fall. Using a polished thin section and an unprepared chip, we will use a FEI Quanta 650 FEG scanning electron microscopy (SEM) combined with Bruker Flat Quad 5060F EDX detector FEI Quanta 650 and Raman spectroscopy, to characterise the mineralogical and organic distribution.
The work will be led by Queenie Chan at Royal Holloway University of London in collaboration Sara Russell at Natural History Museum London.
Timeline:
- Week 1: Literature review
- Week 2: Sample preparation
- Week 3: SEM and data reduction
- Week 4: Raman spectroscopy and data reduction
- Week 5: Comparison to other meteorites, Bennu and Ryugu
- Week 6: Writing up
References: S. J. Clementt et al., (2024) LPSC abstract #1484. D. I. Foustoukos et al., (2024) LPSC abstract #1190. King et al. (2022) Science Advances https://doi.org/10.1126/sciadv.abq3925.