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This is a noon-midnight orbit which crosses the region of the South Atlantic Anomaly in sunlight; the spacecraft pointing strategy is "j-perp", with the ram avoidance constraint in effect. The movie starts with the spacecraft pointing its instruments perpendicular to the magnetic field in the SAA region, and rotating to follow the field until 55131 seconds UT when the magnitude of the model field rises above 0.3 Gauss and the spacecraft swings around to point the instruments antiparallel to the projection of the field into the sun-normal plane. Just as it gets there (about 55299 sec) it runs into the ram-avoidance constraint, and is pushed off-target until about 55665 sec. Once established in the desired attitude, the spacecraft enters eclipse and then coast mode (56505 sec). While the spacecraft is coasting, the field direction rotates roughly in the orbital plane, so that it the instruments are pointing along instead of opposite the projected field when coast mode ends at 57141 sec. The spacecraft swings around to correct this, but before it can finish, the field magnitude drops below 0.3 Gauss again at 57351 sec and j-perp becomes the target.
In the longitudes opposite the SAA, the weak-field region is narrow, and soon after the instruments are pointed perpendicular to the field, at 57609 sec, the field rises above the 0.3 Gauss threshold again. Since the spacecraft is now in the southern hemisphere, it tries to point the instrument look direction parallel to the projected magnetic field, but it enters coast mode at 57669 sec before this is done. Upon exit from coast mode at 58239 sec, the field has rotated into the wrong sector again, so the spacecraft spins around to line up the instruments. The spacecraft remains in this attitude until it approaches the SAA and the field drops below 0.3 Gauss at 59583 sec. After a brief period of dayside coast mode (spacecraft and right-hand bar gauge turn red), the rotation to j-perp is completed and the orbit finishes in this state.
Unlike in the previous orbit (orbit 13847), the spacecraft did not perform a 180° flip when crossing the equator in the weak-field region; I don't kinow why. Anyway, again, the twists and turns of the spacecraft all appear to have reasonable causes in the changing conditions.
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