Particle.news
Download on the App Store

Scientists Directly Detect Torsional Alfvén Waves in the Sun’s Corona

Spectroscopic data from the Inouye Solar Telescope’s Cryo‑NIRSP isolated red‑blue Doppler patterns in superheated iron that reveal twisting motion in the corona.

Overview

  • The findings, led by Professor Richard Morton and published October 24 in Nature Astronomy, provide the first direct spectroscopic evidence of small‑scale torsional Alfvén waves.
  • Researchers used DKIST’s high‑sensitivity Cryo‑NIRSP to track highly ionised iron at about 1.6 million °C, detecting opposite red and blue shifts across coronal magnetic structures.
  • A new analysis removed dominant swaying “kink” motions, exposing the subtle twisting signature long predicted since Hannes Alfvén’s 1942 theory.
  • The observed waves offer a plausible mechanism for heating the million‑degree corona and may contribute to solar‑wind acceleration, with potential links to Parker Solar Probe “switchbacks.”
  • The international collaboration spanning the UK, China, Belgium and the U.S. says further work will quantify energy transport and dissipation to improve space‑weather models.