| Autor: |
Vogt MF; Center for Space Physics, Boston University, Boston, MA, USA., Connerney JEP; NASA Goddard Space Flight Center, Greenbelt, Maryland, USA., DiBraccio GA; NASA Goddard Space Flight Center, Greenbelt, Maryland, USA., Wilson RJ; Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, USA., Thomsen MF; Planetary Science Institute, Tucson, AZ, USA., Ebert RW; Southwest Research Institute, San Antonio, TX, USA.; Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, TX, USA., Clark GB; The Johns Hopkins University Applied Physics Laboratory, Johns Hopkins University, Laurel, MD, USA., Paranicas C; The Johns Hopkins University Applied Physics Laboratory, Johns Hopkins University, Laurel, MD, USA., Kurth WS; Department of Physics and Astronomy, University of Iowa, Iowa City, IA, USA., Allegrini F; Southwest Research Institute, San Antonio, TX, USA.; Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, TX, USA., Valek PW; Southwest Research Institute, San Antonio, TX, USA., Bolton SJ; Southwest Research Institute, San Antonio, TX, USA. |
| Abstrakt: |
At Jupiter, tail reconnection is thought to be driven by an internal mass loading and release process called the Vasyliunas cycle. Galileo data have shown hundreds of reconnection events occurring in Jupiter's magnetotail. Here we present a survey of reconnection events observed by Juno during its first 16 orbits of Jupiter (July 2016-October 2018). The events are identified using Juno magnetic field data, which facilitates comparison to the Vogt et al. (2010, https://doi.org/10.1029/2009JA015098) survey of reconnection events from Galileo magnetometer data, but we present data from Juno's other particle and fields instruments for context. We searched for field dipolarizations or reversals and found 232 reconnection events in the Juno data, most of which featured an increase in | B θ |, the magnetic field meridional component, by a factor of 3 over background values. We found that most properties of the Juno reconnection events, like their spatial distribution and duration, are comparable to Galileo, including the presence of a ~3-day quasi-periodicity in the recurrence of Juno tail reconnection events and in Juno JEDI, JADE, and Waves data. However, unlike with Galileo we were unable to clearly define a statistical x-line separating planetward and tailward Juno events. A preliminary analysis of plasma velocities during five magnetic field reconnection events showed that the events were accompanied by fast radial flows, confirming our interpretation of these magnetic signatures as reconnection events. We anticipate that a future survey covering other Juno datasets will provide additional insight into the nature of tail reconnection at Jupiter. |
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