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arXiv · 2004.11379

Impacts of Dust Grains Accelerated by Supernovae on the Moon

Amir Siraj·Abraham Loeb
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Abstract

There is evidence that ejecta from nearby supernovae have rained down on Earth in the past. Supernovae can accelerate pre-existing dust grains in the interstellar medium to speeds of $\sim 0.01 \mathrm{\;c}$. We investigate the survival and impact of dust grains from supernovae on the moon, finding that supernova dust grains can form detectable tracks with widths of $\sim 0.01 - 0.07 \mathrm{\; \mu m}$ and depths of $\sim 0.1 - 0.7 \mathrm{\; mm}$ in lunar rocks. These tracks could potentially shed light on the timings, luminosities, and directions of nearby supernovae.

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Amir Siraj, Abraham Loeb. 2020-04-23. Impacts of Dust Grains Accelerated by Supernovae on the Moon. https://doi.org/10.3847/2041-8213%2Fab93d5

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