A few years back we looked into iron-60 from recent supernovae. I pondered if such were connected to our local bubble. Today we heard that the local bubble indeed has something to do with Fe-60 in Antarctic ice... but this iron's a lot younger. It arrived between 40,000 and 124,000 years ago
, say Catherine Zucker, Seth Redfield, Sara Starecheski, Ralf Konietzka, and Jeffrey L. Linsky.
This is about as low as, perhaps, a consistent Antarctic ice core can go, since 122kBC is MIS-5e/Eemian. At least easily.
The explosion which hollowed out this gap, and created the iron, out in space; has been dated 1.2Mya in Upper Centaurus Lupus. Joshua Peek offered some help, whom we remember from 2024 (with Opher and, sigh, Loeb). The paper does not rule out earlier excursions into other iron-poor bubbles, as Zucker's crew point out.
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