Tail substorm dynamics captured by HENA
Ions drifting in from nightside filling the plasmasheet
Ions accelerated earthward evacuating plasmasheet densities
Accelerated ions reach lower altitudes.
Plasmasheet starts refilling.
- HENA observes ENAs coming from 12 Re in the magnetotail.
- The observed tail propagates Earthward at substorm dipolarization.
- Correlated with auroral substorm onset.
- So far observed for 4 October 2000 and 19 September 2000 storm.