Figure 1. Sketch depicting the asymmetric antiparallel reconnection with the local magnetopause coordinates [L, M, N] superimposed at the right.

The magnetosheath is at the top, and the magnetosphere is at the bottom. Solid black curves indicate magnetic field lines, and solid green curves indicate stream lines. Dashed black lines indicate the four separatrix lines, which intersect at the X point. Stagnant point S is located at the dashed green line, on which the flow velocity in the N direction is zero. The blue box marks the diffusion region with a width of 2δ and a length of 2L. The red line with the arrows at both ends indicates that the spacecraft crosses the exhaust region from the magnetosheath to the magnetosphere or vice versa.