SPRG Seminars
October 7, 2008:
"Tail Reconnection Triggering Substorm Onset "
Vassilis Angelopoulos
For 30 years the onset mechanism of the explosive release of energy in Earth's magnetosphere called a substorm
has been sought after with fervor, as it is the key to answering which fundamental instability undelies one of the most violent particle acceleration processes in this nearby astrophysical laboratory. The THEMIS mission in its first traversal of the magnetotail has made the most convincing observations to date that the substorm onset is triggered by magnetotail reconnection. I will summarize the lessons learned from the first year of magnetotail observations by THEMIS, describe the aspects of the observations that are still cause for some debate, the mission adjustments to address such remaining questions and the new paradigm that is gradually building up regarding magnetospheric coupling to the ionosphere.