Japan Geoscience Union Meeting 2025

Presentation information

[E] Oral

P (Space and Planetary Sciences ) » P-AE Astronomy & Extrasolar Bodies

[P-AE18] Exoplanets

Fri. May 30, 2025 1:45 PM - 3:15 PM 304 (International Conference Hall, Makuhari Messe)

convener:Takanori Kodama(Earth-Life Science Institute, Institute of Science Tokyo), Yui Kawashima(Kyoto University), Shota Notsu(Earth and Planetary System Science Group, Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo), Mayuko Mori(Astrobiology Center), Chairperson:Shota Notsu(Earth and Planetary System Science Group, Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo), Kazumasa Ohno(National Astronomical Observatory of Japan)


3:00 PM - 3:15 PM

[PAE18-18] Formation of super-Earths: effects of water enrichment and partitioning

★Invited Papers

*Tadahiro Kimura1,2, Tim Lichtenberg2 (1.UTokyo Organization for Planetary Science, 2.Kapteyn Astronomical Institute, the University of Groningen)

Keywords:super-Earth/sub-Neptune, primordial atmosphere, planet formation

Super-Earths and sub-Neptunes are among the most common types of exoplanets discovered to date, yet their formation and atmospheric evolution remain poorly understood. The formation of primordial atmospheres on these planets is a critical area of study in understanding the diversity and evolution of exoplanetary systems. This talk explores the mechanisms by which these atmospheres form, with a particular focus on the role of water enrichment and its partitioning between the interior and the atmosphere. We discuss how the accretion of volatile-rich planetesimals and chemical reaction between the atmosphere and magma ocean, as well as the partitioning of water, contribute to the atmospheric properties. By integrating insights from planetary formation models and primordial atmospheric formation and evolution, this talk aims to provide a comprehensive understanding of how water-rich super-Earths and sub-Neptunes acquire and maintain their primordial atmospheres and to give implications for the ongoing and near-future observations.