These movies show ion trajectories in a magnetic field configuration obtained from a global three-dimensional MHD simulation. The global model was run for more than two hours, with solar wind incident on the earth from the left of the image with a pressure of 1 nP and a northward field strength of 2.5 nT.

Ions were injected near the last closed field line on the earth-sun line. Bouncing ions convect away from the subsolar point, leading to the widening of the ion `beam'. (Note curvature drift motions would cause them to all drift towards the dawn side.) The detail view version of this movie uses the same data.

nota bene: The mpeg compression scheme used to produce this movie uses about a 4-frame look-ahead to interpolate between frames. This produces an artifact wherein some particles lead the bunch by a few frames.