Overview
- Namekata et al. report in Nature Astronomy that EK Draconis produced a coronal mass ejection with distinct hot and cool plasma components captured in real time.
- Hubble far‑ultraviolet lines traced ~100,000 K plasma moving at 300–550 km/s, followed about 10 minutes later by ~10,000 K gas at roughly 70 km/s seen in Hα from synchronized ground telescopes in Japan and Korea.
- The hotter component carried much greater energy than the cooler material, raising the prospect of shocks and energetic particles that can erode or chemically modify early atmospheres.
- A companion arXiv analysis synthesizing five years of observations finds four of fifteen superflares linked to fast prominence eruptions and notes a case with possible X‑ray coronal dimming consistent with a CME.
- The survey constrains rates and impacts, including a lower‑limit CME association of 27%, occurrence rates for EK Draconis and V889 Hercules, and a first lower‑limit super‑CME mass‑loss rate for EK Draconis comparable to stellar wind at a similar age.