Queen Mary University of London has led a study which describes the first direct measurement of how energy is transferred from the chaotic electromagnetic fields in space to the particles that make up the solar wind, leading to the heating of interplanetary space.
The study, published in Nature Communications and carried out with University of Arizona and the University of Iowa, shows that a process known as Landau damping is responsible for transferring energy from the electromagnetic plasma turbulence in space to electrons in the solar wind, causing their energisation.
This process, named after the Nobel-prize winning physicist Lev Landau (1908-1968), occurs when a wave travels through a plasma and the plasma particles that are travelling at a similar speed absorb this energy, leading to a reduction of energy (damping) of the wave.
Although this process had been measured in some simple situations previously, it was not known whether it would still operate in the highly turbulent and complex plasmas occurring naturally in space, or whether there would be a different process entirely.
Read more at Queen Mary University of London
Image: This is an illustration of the MMS spacecraft measuring the solar wind plasma in the interaction region with the Earth's magnetic field. (Credit: NASA)