The rate of supernovae (SNe) in our local galactic neighborhood within a distance of ~100 parsec from Earth (1 parsec (pc)=3.26 light years) is estimated at 1 SN every 2-4 million years (Myr), based on the total SN-rate in the Milky Way (2.0±0.7 per century,). Recent massive-star and SN activity in Earth’s vicinity may be evidenced by traces of radionuclides with half-lives t1/2 ≤100 Myr-, if trapped in interstellar dust grains that penetrate the Solar System (SS). One such radionuclide is 60Fe (t1/2=2.6 Myr), which is ejected in supernova explosions and winds from massive stars,,. Here we report that the 60Fe signal observed previously in deep-sea crusts,, is global, extended in time and of interstellar origin from multiple events. Deep-sea archives from all major oceans were analyzed for 60Fe deposition via accretion of interstellar dust particles. Our results, based on 60Fe atom-counting at state-of-the-art sensitivity, reveal 60Fe interstellar influxes onto Earth 1.7–3.2 Myr and 6.5–8.7 Myr ago. The measured signal implies that a few percent of fresh 60Fe was captured in dust and deposited on Earth. Our findings indicate multiple supernova and massive-star events during the last ~10 Myr at nearby distances ≤100 pc.
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