New empirical kinetics of iron oxidation by CO2 applied to micrometeorites imply a CO2-rich Archean atmosphere
The oxidation state of iron-type micrometeorites preserved in 2.7 Ga sedimentary rocks offers a potential proxy for reconstructing Archean atmosphericβ¦
published a paper that melts little balls of iron in the lab to mimic how they melt in the upper atmosphere. The new kinetic data helps us use micrometeorites found in rocks from billions of years ago to determine the composition of ancient air at that time. www.sciencedirect.com/science/arti...
10.02.2026 02:03 β
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Seafloor weathering can explain the disparate durations of Snowball glaciations | Geology | GeoScienceWorld
Earth was a frozen over, "Snowball Earth" twice between 720-635 m.y. ago. The 1st glaciation lasted a huge 56 m.y. (almost like the dinosaur extinction to us) but no one knows how. My group just published a mechanistic explanation. pubs.geoscienceworld.org/gsa/geology/...
04.12.2025 07:13 β
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Climate_Experts_Review_of_DOE_CWG_Report.pdf
is impressed that 85+ climate scientists quickly wrote a 400-page report rebutting a lot of misleading info and misrepresentations in a recent DOE climate report attempting to downplay global heating from CO2 emissions. drive.google.com/file/d/1PwAR...
07.09.2025 21:25 β
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Commentary on an article by @sebastienviscardy.bsky.social, me and Kevin Zahnle arguing how Curiosity rover detections of methane are more likely methane contamination inside the rover than in the martian atmosphere.
bsky.app/profile/eos....
14.05.2025 02:55 β
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my book, βAstrobiology: A Very Short Introductionβ is now published in Chinese and available to 1.2B people for whom Chinese is a 1st or 2nd language (1st Ed with updates, Yilin Press, Nanjing). Coming soon: 2nd Ed. (OUP) in English in 2026/7, with updates on planetary science, origin of life, etc.
28.04.2025 19:07 β
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Origin of biological homochirality by crystallization of an RNA precursor on a magnetic surface
Homochirality was achieved by the spin-selective crystallization of a racemic RNA precursor on a magnetite surface.
My 2 cents: The CISS effect (chirality induced spin selectivity) is the best answer to date. It empirically produces homochirality in biologically-relevant molecules unlike previous ideas with little/no feasibility. Underlying theory of CISS remains TBD. See, e.g., www.science.org/doi/full/10....
28.04.2025 18:27 β
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At the same time, Dirac saw defining what exactly is a measurement and what exactly is associated collapse as difficult problems that future theory needed to resolve and perhaps turn into quite different problems. Iβll happily defer to Dirac.
25.04.2025 18:59 β
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I was educated with the Bohr interpretation that an observation is the interaction of a quantum phenomenon (e.g. an electron) with a classical apparatus, which doesnβt require a conscious observer. The quantum measurement ends when macroscopically recorded, which doesnβt require a mind.
25.04.2025 18:55 β
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Iβm having trouble seeing how your examples, Ray, are qualitatively different from SchrΓΆdingerβs Cat & its various proposed solutions. This is a problem from 90 years ago.
24.04.2025 20:10 β
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Haas, Tutolo & Catling 2025. A phosphorus budget of soda lakes finds major biological sinks, implying abundant phosphate-availability at the origin of life.
My group's most recent paper: We quantified phosphorus fluxes in soda lakes, showing that without biology, soda lakes worldwide would have phosphate levels suitable for prebiotic synthesis of RNA. This answers a 70-year-old βphosphate problem of the origin of lifeβ
doi.org/10.1016/j.gc...
17.02.2025 03:24 β
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