ABSTRACT

To date, the Magnetospheric Multiscale mission has observed magnetic reconnection at the dayside magnetopause from September 2015 to March 2016 with four spacecraft and plasma time resolution up to 100x faster than previous missions, and thus sufficient to capture electron scale phenomena. The data includes charged particles, electric and magnetic fields during encounters with electron dissipation regions when the spacecraft were maintained in a tetrahedral configuration ranging from 10-160 km on a side. The full three-dimensional electron distribution functions, observed every 30 ms, revealed crescent-shaped features that are predicted to result from mixing of magnetosheath and magnetospheric particles and acceleration of electrons by electric-field components directed normal to the magnetopause. The observed currents and electric fields reveal the dissipation of magnetic energy. The reconnection X-line is marked by near magnetic null regions that occur on the magnetosheath side of the dissipation region. Electric field components parallel to the local magnetic field are also observed in this region. Localized reconnection dissipation is also observed along the separatrices between isolated (inflow) and connected (exhaust) magnetic fields. MMS opens up the physics of reconnection to direct observations that reveal expected features but also challenge us with a wealth of complex detail holding clues as to its dynamic response and the causes of explosive behavior.

About the Speaker:

Thomas E. Moore earned the B.S. in Physics in 1970, and the M.A.T. in 1971, from the University of New Hampshire. He received the Ph.D. in Astrogeophysics from the University of Colorado, Boulder in 1978. Back at UNH, he worked on the dynamics of the plasma environment at geosynchronous orbit, and the first multi-point observations to reveal moving space weather fronts. He also was active in the observation of plasma and energetic particles above auroral displays from sounding rocket platforms. Dr. Moore joined NASA at Marshall Space Flight Center in 1983 as a member of the science team for the Retarding Ion Mass Spectrometer on the Dynamics Explorer-1 Satellite. He supplied plasma spectrometers for the TOpside Probe of the Auroral Zone (TOPAZ) series of sounding rocket payloads, the ARCS series of active experiment payloads, and the SCIFER and CAPER rocket payloads. At MSFC, he became the principal investigator for the Thermal Ion Dynamics Experiment and Plasma Source Instrument for the ISTP POLAR spacecraft. Dr. Moore joined the Goddard Space Flight Center in 1997, as mission scientist for the IMAGE mission, lead co-investigator for the Low Energy Neutral Atom imager on IMAGE, and to pursue broader interests in heliospheric and planetary plasma heating and outflow. He is a Fellow of the American Geophysical Union, having served as awards committee member, section secretary, and program committee member, and associate editor for the Space Physics and Aeronomy section. He served as a member of the Solar Probe science definition team, The Sun Earth Connections Advisory Subcommittee, as a co-chair of the first NASA “Heliophysics” Roadmap Committee, as study scientist for the Magnetotail Constellation Mission, and as Co-convener for the 2015 Conference on Measurement Techniques in Solar and Space Physics. He is a co-investigator on the Interstellar Boundary Explorer mission, and the Magnetospheric Multiscale mission, as Project Scientist.