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#taenite — Public Fediverse posts

Live and recent posts from across the Fediverse tagged #taenite, aggregated by home.social.

  1. We can interpret this amazing image of a forming solar system (HL Tauri, from the Alma array; ESO 2014).

    Iron meteorites with and domains forming a Widmanstätten pattern tell us that in systems like this or our own solar system:

    –planetesimals had already formed and differentiated, while a heat source (decay of 26-Al) was still available.

    –they were on the order of 100's of km in diameter, with enough rock to insulate the slowly-cooling core.

  2. The solid-state diffusion of iron and nickel into and domains forms the Widmanstätten pattern in iron meteorites. The growth of these domains has been calibrated with temperature.

    The meteorite pictured (Tambo Quemado, Peru, type IIIB) suggests a cooling rate of 1.2 °C per million years; modelling suggests this occurred in a planetesimal ~ 200 km in radius (which was later disrupted and fragments of the core exposed to space) (Goldstein & Short, 1967).