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arXiv · 2510.22112

Coronal Mass Ejections from Young Suns: Insights from Solar and Stellar Observations and Models

Kosuke Namekata
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Abstract

Recent discoveries have revealed exoplanets orbiting young Sun-like stars, offering a window into the early solar system. These young stars frequently produce extreme magnetic explosions known as superflares potentially leading to fast and massive coronal mass ejections (CMEs). Recent research have highlighted the importance of stellar CMEs, as these events and associated particles can trigger atmospheric loss and initiate chemical reactions in planetary atmospheres. However, the observation of these associated CMEs remains largely unexplored, marking a crucial first step in assessing the particle environment. Here we present the results of 5-years multi-wavelength observations of young Sun-like stars, providing the critical clues to the common picture of solar and stellar CMEs. This comprehensive study suggests that further advancing the use of solar model could provide the first empirical inputs into calculations of atmospheric escape/chemical reactions for young planets.

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Kosuke Namekata. 2025-10-25. Coronal Mass Ejections from Young Suns: Insights from Solar and Stellar Observations and Models. https://arxiv.org/abs/2510.22112

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