Coronal Mass Ejections from the Young Sun: Deceleration-Powered Solar Energetic Particles as a Self-Extinguishing Forcing of the Early Earth
Abstract
At ∼3.9~Ga (stellar age ∼0.6~Gyr), the young Sun was far more magnetically active than today. It launched ∼102 large, fast coronal mass ejections (CMEs) per year into a denser, more magnetized wind. We follow these eruptions to Earth's atmosphere with a semi-analytic model chain. We find that a CME launched at v0∼3−−4e3unitkm s−1 dissipates ΔEk∼6e25unitJ as it decelerates, an amount set only by its launch and final speeds. Diffusive shock acceleration converts ∼10\% of this energy into solar energetic particles (SEPs), whose deposition depth depends mainly on a spectral break energy Eb. We show that the stronger field moves the Alfvén surface, inside which the magnetic field controls the wind, from ∼10--25Rsun to ∼40--60Rsun, so CME shocks deliver over ten times the particle fluence of flares. Because the forcing is powered by deceleration, it follows the measured wind history (Ṁ∝ t−2.3) and declines as ∼ t−3. It was ∼50--100 times stronger at 3.9~Ga than at 2~Ga and several hundred times today's level. This decline, strongest when the Sun was faintest, is what greenhouse solutions of the faint young Sun (FYS) problem usually impose by hand. The magnitude is small: SEP-driven N2O adds at most a few unitW m−2 to a 20--40unitW m−2 greenhouse requirement, and only if a fractal organic haze extends its lifetime. Counting energy deposited below a survival level near 1~hPa, we find the particles fix ∼4e10--4e11unitmol N yr−1, which could supply prebiotic feedstock to surface pools. The largest uncertainties are Eb, the event rate, the survival depth, and the N2O lifetime.
Related
- Breakout/Interchange Reconnection as a driver of Jets, Fast Coronal Mass Ejection, and Solar Energetic Particles
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- Influence of local and global solar magnetic fields on medium-term forecasting of the number and parameters of coronal mass ejections
- Coronal Mass Ejections from Young Suns: An Observational View through the Solar-Stellar Connection
- A Global Magnetohydrodynamic Simulation of the Birth and Cannibalism of Homologous Coronal Mass Ejections
BibTeX
@misc{panasenco2026coronal,
title = {{Coronal Mass Ejections from the Young Sun: Deceleration-Powered Solar Energetic Particles as a Self-Extinguishing Forcing of the Early Earth}},
author = {Olga A. Panasenco},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.08758},
eprint = {2610.08758},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.08758},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Coronal Mass Ejections from the Young Sun: Deceleration-Powered Solar Energetic Particles as a Self-Extinguishing Forcing of the Early Earth
AU - Olga A. Panasenco
PY - 2026
DA - 2026/10/06
PB - arXiv
DO - 10.48550/arxiv.2610.08758
UR - https://arxiv.org/abs/2610.08758
AB - At ∼3.9~Ga (stellar age ∼0.6~Gyr), the young Sun was far more magnetically active than today. It launched ∼10^2 large, fast coronal mass ejections (CMEs) per year into a denser, more magnetized wind. We follow these eruptions to Earth's atmosphere with a semi-analytic model chain. We find that a CME launched at v_0∼3−−4e3unitkm s^−1 dissipates ΔE_k∼6e25unitJ as it decelerates, an amount set only by its launch and final speeds. Diffusive shock acceleration converts ∼10\% of this energy into solar energetic particles (SEPs), whose deposition depth depends mainly on a spectral break energy E_b. We show that the stronger field moves the Alfvén surface, inside which the magnetic field controls the wind, from ∼10--25Rsun to ∼40--60Rsun, so CME shocks deliver over ten times the particle fluence of flares. Because the forcing is powered by deceleration, it follows the measured wind history (Ṁ∝ t^−2.3) and declines as ∼ t^−3. It was ∼50--100 times stronger at 3.9~Ga than at 2~Ga and several hundred times today's level. This decline, strongest when the Sun was faintest, is what greenhouse solutions of the faint young Sun (FYS) problem usually impose by hand. The magnitude is small: SEP-driven N_2O adds at most a few unitW m^−2 to a 20--40unitW m^−2 greenhouse requirement, and only if a fractal organic haze extends its lifetime. Counting energy deposited below a survival level near 1~hPa, we find the particles fix ∼4e10--4e11unitmol N yr^−1, which could supply prebiotic feedstock to surface pools. The largest uncertainties are E_b, the event rate, the survival depth, and the N_2O lifetime.
ER -