The Astronomical Records in… Trees?

We can learn a lot about our galaxy by looking to the stars, but we can also reveal a lot about our cosmic history from... Dead trees?

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Sources:

https://www.radioactivity.eu.com/site/pages/RadioCarbon.htm
https://www.cambridge.org/core/journals/radiocarbon/article/intcal20-northern-hemisphere-radiocarbon-age-calibration-curve-055-cal-kbp/83257B63DC3AF9CFA6243F59D7503EFF
https://www.dateringsmetoder.dk/wp-content/uploads/2018/06/A-signature-of-cosmic-ray-increase-in-AD774.pdf
https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/2014GL059874
https://arxiv.org/pdf/1212.0490.pdf
https://doi.org/10.1017/S1473550420000348
https://www.eurekalert.org/pub_releases/2020-11/uoca-trm111120.php
https://pwg.gsfc.nasa.gov/polar/EPO/auroral_poster/aurora_all.pdf