activity
20242026
collaborators

4 papers

astro-ph.SR2026

Multiwavelength Campaign Observations of a Young Solar-type Star, EK Draconis. III. Comparison between Starspot Mapping, Zeeman Doppler Imaging, and Multiwavelength Variability

Kai Ikuta, Kosuke Namekata, Pascal Petit +12

Recent simultaneous multiwavelength observations of a nearby young solar-type star EK Dra in the optical, H spectrum, and X-ray, have provided evidence for stellar prominence e…

astro-ph.SR2025

Do Young Suns Produce Frequent, Massive CMEs? Results from Five-year Dedicated Optical Observations of EK Draconis and V889 Hercules

Kosuke Namekata, Hiroyuki Maehara, Yuta Notsu +4

We report results from a five-year (132-night) dedicated observational campaign targeting two nearby young solar-type stars, EK Draconis (50-125 Myr age) and V889 Hercules ($…

astro-ph.SR2025

Discovery of multi-temperature coronal mass ejection signatures from a young solar analogue

Kosuke Namekata, Kevin France, Jongchul Chae +14

Coronal mass ejections (CMEs) on the early Sun may have profoundly influenced the planetary atmospheres of early Solar System planets. Flaring young solar analogues serve as excell…

astro-ph.SR2024

Multiwavelength Campaign Observations of a Young Solar-type Star, EK Draconis. II. Understanding Prominence Eruption through Data-Driven Modeling and Observed Magnetic Environment

Kosuke Namekata, Kai Ikuta, Pascal Petit +15

EK Draconis, a nearby young solar-type star (G1.5V, 50-120 Myr), is known as one of the best proxies for inferring the environmental conditions of the young Sun. The star frequentl…