July 21, 2017, 1:00 pm - 2:00 pm
July 21, 2017, 1:00 pm - 2:00 pm, Heliophysics Director's Seminar, Hosted by 673
The Role of Magnetotails in Coupling Energy from the Solar Wind to the Ionosphere
Eftyhia Zesta
Planetary magnetospheres are compressed and confined on the side facing the Sun and stretched out into long magnetotails on the side facing away. These magnetotails are quite dynamic, they flap in the solar wind and particles are often energized there. Magnetotails are also the primary source of polar auroras that fill planetary ionospheres with light. Those living through Earth's arctic winters have long known that the brightest auroras are seen in the hours around midnight. However, early in the space age it was widely believed that the precipitating electrons creating the aurora came from the solar wind. The fact that aurora were concentrated on the side facing away from the Sun was a particular mystery until satellites discovered and mapped our magnetosphere's long magnetic tail. So what else are magnetotails good for, why should we care, and what mysteries remain to be answered?
The Magnetotail of Ganymede
Glyn Collinson
On the 27th of June 1996, the NASA Galileo spacecraft made humanities first flyby of Jupiter's largest moon, Ganymede, discovering that it is unique to science in being the only moon known to possess an internally generated magnetic dynamo field. Although Galileo carried a plasma spectrometer, the Plasma Subsystem (PLS), converting its highly complex raw data stream into meaningful plasma moments (density, temperature, velocity) is extremely challenging, and was only ever performed for the second (out of six) Ganymede flybys. Resurrecting the original Galileo PLS data analysis software, we processed the raw PLS data from G01, and for the first time cracked open the data. We found the structure of the magnetotail flown through on G01 to be even stranger than had been thought possible.
Magnetospheric Multiscale during the Maha Phase: Quest for Magnetotail Reconnection
William Paterson
During its first two years of operation, the MMS mission, with apogee at 12 RE, was dedicated to a search for reconnection regions at Earth's dayside magnetopause. During that time the plasma analyzers of the Fast Plasma Investigation (FPI) functioned superbly, as evidenced by a wealth of publications making substantial use of FPI data. Beginning in January of 2016, apogee was raised to 25 RE in preparation for the magnetotail phase, which is now in progress. The hot and tenuous magnetotail environment presents new observational challenges for FPI. In this presentation we briefly summarize some achievements of the dayside campaign and discuss ongoing efforts of the FPI team as they relate to the magnetotail phase of the mission.
