Hotting up the Solar Wind

19 Aug 2012

At ... Dr Kareem Osman from Warwick University is looking at why solar wind is hotter than it should be - or why does it not conform with the consensus view. It gets hotter as it expands towards the outer solar system and her study will concentrate on unravelling plasma turbulence. Now, this doesn't appear to be the kind of turbulence in the dictionary definition, mainly associated with buffeting winds. Turbulence in astronomy is a feature of stars and stellar winds, accretion discs, galaxies, and even the material between the galaxies. Turbulence stretches and bends magnetic field lines and helps form 'current sheets' which are distributed randomly in space. Current sheets may heat and accelerate plasma - but is this current as in an electrical current or is this another misuse of a word by astronomers?