Contrasting Properties of two Ion-Scale Magnetopause Flux Ropes

In this paper, we present results from the MMS constellation encountering two ion-scale, magnetopause flux ropes. The two flux ropes exhibit very different properties and internal structure. In the first flux rope, there are large differences in the currents observed by different satellites, indicating variations occur over sub-di spatial scales, and time scales on the order of the ion gyro period. In addition, there is intense wave activity and particle energization. The interface between the two flux ropes exhibits oblique whistler wave activity. In contrast, the second flux rope is mostly quiescent, exhibiting little activity throughout the encounter. Changes in the magnetic topology and field line connectivity indicates we are observing flux rope coalescence.