Cosmogenic 10Be as a Tracer for Recent Heliospheric Encounters with Interstellar Cold Clouds
Abstract
Recent works suggest there are periods when the Sun encountered massive interstellar cold clouds which compressed the heliosphere to within Earth's orbit, exposing Earth to interstellar galactic cosmic rays and energetic particles of heliospheric origin. We model 10bE production in Earth's atmosphere during possible interstellar cloud encounters and supernovae. We find that, if the heliosphere is compressed to 0.2 AU (r_TS=0.12 AU), the 10Be production rate is elevated 9x above the background. To be distinguished in marine sediments (iron-manganese crusts) beyond terrestrial variability, this signal must be sustained for >0.01 Myr (>0.5 Myr). A 0.7 AU (r_TS=0.4 AU) compression increases the 10Be production rate 3x above the background, which may be detectable if the event lasts >1 Myr. We find that the 10Be peak observed by Koll et al. (2025) 10 Ma is too prolonged to be produced by a supernova, but could be attributed to an interstellar cloud crossing.
Fields of Study & Subjects
Solar and Space Plasma Dynamics
Geology and Paleoclimatology Research
Astrophysics and Cosmic Phenomena
Publication details
- Journal / source
- arXiv (Cornell University)
- Publication date
- 12 January 2026
- Document type
- Preprint