Open Access

Magnetic reconnection in large-scale cosmic plasmas

Earth, Planets and Space201453:BF03353288

Received: 7 July 2000

Accepted: 23 October 2000

Published: 26 June 2014


X-ray emitting hot plasmas of a temperature 2–12 keV, associated with galaxy clusters, constitute the most dominant form of baryons in the universe. The plasma is thought to be magnetized at least to 0.1–1 nT, although the β value is relatively high at 10–100. The plasma is confined by gravity of each cluster in a stable manner, but the member galaxies are moving through it with an approximately transonic speed. Therefore, the plasma must be in a magnetohydrodynamically turbulent condition, where frequent magnetic reconnection is expected to take place. Mainly based on observations with the ASCA X-ray Observatory, evidence for such magnetic reconnection is accumulating.