RESUMEN
There is ample evidence for magnetic reconnection in the solar system, but it is a nontrivial task to visualize, to determine the proper approaches and frames to study, and in turn to elucidate the physical processes at work in reconnection regions from in-situ measurements of plasma particles and electromagnetic fields. Here an overview is given of a variety of single- and multi-spacecraft data analysis techniques that are key to revealing the context of in-situ observations of magnetic reconnection in space and for detecting and analyzing the diffusion regions where ions and/or electrons are demagnetized. We focus on recent advances in the era of the Magnetospheric Multiscale mission, which has made electron-scale, multi-point measurements of magnetic reconnection in and around Earth's magnetosphere.
RESUMEN
The IMAGE spacecraft uses photon and neutral atom imaging and radio sounding techniques to provide global images of Earth's inner magnetosphere and upper atmosphere. Auroral imaging at ultraviolet wavelengths shows that the proton aurora is displaced equatorward with respect to the electron aurora and that discrete auroral forms at higher latitudes are caused almost completely by electrons. Energetic neutral atom imaging of ions injected into the inner magnetosphere during magnetospheric disturbances shows a strong energy-dependent drift that leads to the formation of the ring current by ions in the several tens of kiloelectron volts energy range. Ultraviolet imaging of the plasmasphere has revealed two unexpected features-a premidnight trough region and a dayside shoulder region-and has confirmed the 30-year-old theory of the formation of a plasma tail extending from the duskside plasmasphere toward the magnetopause.
RESUMEN
Magnetic reconnection is a fundamental physical process in plasmas whereby stored magnetic energy is converted into heat and kinetic energy of charged particles. Reconnection occurs in many astrophysical plasma environments and in laboratory plasmas. Using measurements with very high time resolution, NASA's Magnetospheric Multiscale (MMS) mission has found direct evidence for electron demagnetization and acceleration at sites along the sunward boundary of Earth's magnetosphere where the interplanetary magnetic field reconnects with the terrestrial magnetic field. We have (i) observed the conversion of magnetic energy to particle energy; (ii) measured the electric field and current, which together cause the dissipation of magnetic energy; and (iii) identified the electron population that carries the current as a result of demagnetization and acceleration within the reconnection diffusion/dissipation region.