Why in the news?

• Studies confirmed the presence of Alfvén Waves in Solar Corona.

Alfvén Waves

• What is it?: Alfvén Waves are magnetohydrodynamic (MHD) waves– the oscillations that occur in a plasma (ionised gas) in the presence of a magnetic field.
• Features:
  • Wave type: Transverse waves- Oscillations perpendicular to the direction of propagation.
  • Medium: Requires ionised gas or plasma with a magnetic field.
  • Energy transport: Carries energy and momentum through plasma without significant mass transport.
• Occurrence in Nature:
  • Detected in the solar corona and solar wind, explaining how the corona remains millions of degrees hotter than the solar surface.
  • Earth’s magnetosphere: Observed in auroral regions — they accelerate charged particles that produce northern and southern lights.
  • Found in interstellar and intergalactic mediums, accretion disks, and magnetized jets.
• Applications:
  • Solar Space Research: Explains solar wind acceleration and space weather phenomena affecting Earth’s satellites and communication systems.
  • Astrophysics: Helps understand magnetic field dynamics in stars and galaxies.
  • Plasma Physics and Fusion Research: Crucial in controlling plasma behaviour in fusion energy experiments.
  • Geophysics: Provides insights into magnetosphere-ionosphere coupling processes.