• Nichols, C.I.O.; Bryson, J.F.J.; Cottrell, R.D.; Fu, R.R.; Harrison, R.J.; Herrero-Albillos, J.; Kronast, F.; Tarduno, J.A.; Weiss, B.P.: A Time-Resolved Paleomagnetic Record of Main Group Pallasites: Evidence for a Large-Cored, Thin-Mantled Parent Body. Journal of Geophysical Research : Planets 126 (2021), p. e2021JE006900/1-21

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Several paleomagnetic studies have been conducted on 􏰂ve main group pallasites: Bren- ham, Marjalahti, Springwater, Imilac and Esquel. These pallasites have distinct cooling histories, meaning that their paleomagnetic records may have been acquired at di􏰁erent times during the thermal evolution of their parent body. Here we compile new and existing data to present the most complete time-resolved paleomagnetic record for a planetesimal, which includes a period of quiescence prior to core solidi􏰂cation as well as dynamo ac- tivity generated by compositional convection during core solidi􏰂cation. We present new paleomagnetic data for the Springwater pallasite, which constrains the timing of core solid- i􏰂cation. Our results suggest that in order to generate the observed strong paleointensities (∼ 65 􏰀 95 μT), the pallasites must have been relatively close to the dynamo source. Our thermal and dynamo models predict that the main group pallasites originate from a plan- etesimal with a large core (> 200 km) and a thin mantle (< 70 km). The density of our model large-cored planetesimals is similar to the predicted density of the asteroid (16) Psyche. We therefore suggest that it is plausible that the main group pallasites originated from a Psyche-like parent body.