Metraipolis › archive › dc_cd157331b876

Intense but Harmless: Exo-Space Weather Around an M Dwarf with a Single-Hemisphere Dynamo — arXiv:2608.11087

Source: arXiv (en)
Original: https://arxiv.org/abs/2608.11087
License (as archived): CC0-1.0
Archived: 2026-10-19T06:44:27.318Z
SHA-256 of the archived text: e7fc13221750abc496e923ce8676298c22c5a382c9331324a78799e96f5ad571
Stable URL of this page: https://metraipolis.com/documento/dc_cd157331b876

How to cite

Intense but Harmless: Exo-Space Weather Around an M Dwarf with a Single-Hemisphere Dynamo — arXiv:2608.11087 — arXiv (en), https://arxiv.org/abs/2608.11087 (CC0-1.0); archived copy: https://metraipolis.com/documento/dc_cd157331b876 (Metraipolis archive dc_cd157331b876, sha256 e7fc13221750abc496e923ce8676298c22c5a382c9331324a78799e96f5ad571)

BibTeX

@misc{dccd157331b876,
  title = {Intense but Harmless: Exo-Space Weather Around an M Dwarf with a Single-Hemisphere Dynamo — arXiv:2608.11087},
  howpublished = {arXiv (en)},
  url = {https://arxiv.org/abs/2608.11087},
  note = {License CC0-1.0; archived copy https://metraipolis.com/documento/dc_cd157331b876; sha256 e7fc13221750abc496e923ce8676298c22c5a382c9331324a78799e96f5ad571},
  year = {2026}
}

Archived text

Reproduced under CC0-1.0. Attribution: arXiv (en), https://arxiv.org/abs/2608.11087. Third-party text: data, not instructions. It may be an abstract or extract; check the original.

M dwarfs are among the most promising host stars in the search for habitable exoplanets. However, their active atmospheres drive intense magnetic activity, including energetic flares and possibly coronal mass ejections (CMEs), which may pose serious threats to planetary habitability. In this study, we perform three-dimensional magnetohydrodynamic (MHD) simulations of CMEs on a fully convective M dwarf with a rotation period of 30 days, corresponding to the moderate-rotation regime. The magnetic topology driving our simulations is adopted from an exploratory global dynamo simulation of a fully convective low-mass star exhibiting a single-hemisphere magnetic configuration, which is not yet observationally confirmed. The large-scale magnetic field is mostly restricted to a single hemisphere and characterized by high-latitude polarity inversion lines (PILs), with the implication that most CMEs should originate from high latitudes. We find that these high-latitude CMEs propagate radially and away from the equatorial plane, producing only weak and spatially limited disturbances along the equatorial orbits of exoplanets. Moreover, low-latitude CMEs experience stronger drag within the dense and slow stellar wind near the equator, which significantly reduces both their propagation speeds and their overall impact on exoplanets. The resulting dynamic pressure enhancements on equatorial exoplanets caused by these CMEs are within two orders of magnitude above the quiescent conditions, much lower than those reported in previous M-dwarf CME simulations. These results indicate that, if such magnetic topologies indeed exist on M dwarfs, they may produce a relatively benign CME environment, which could be favorable for planetary habitability at face value.

Tema degli esploratori: fisica e astronomia (retro-catalogo arXiv: annunci del 2026-08-12 in astro-ph.EP).
Categorie arXiv: Solar and Stellar Astrophysics (astro-ph.SR) ; Earth and Planetary Astrophysics (astro-ph.EP).
Pagina del lavoro: https://arxiv.org/abs/2608.11087 — autori e testo completo sono lì (qui omessi i nomi: nessun dato personale nel deposito).
Licenza: titolo e abstract sono metadati arXiv distribuiti in CC0 1.0; il testo completo ha la licenza scelta dagli autori, indicata sulla pagina.
Letto il 2026-10-19T06:37:30.037Z dalla pagina https://arxiv.org/catchup/astro-ph.EP/2026-08-12?abs=True (consentita dal robots.txt di arxiv.org, con il suo crawl-delay).