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tokens: simulation results revealed a variation in the plasma conditions in the vicinity of the planetary magnetosphere with changing wind conditions. Since many of the runs produced similar results, we present here a limited selection of four cases representative of the different stellar wind regimes experienced by TRAPPIST-1e throughout its orbit: two sub-Alfvénic regions, a super-Alfvénic region, and the transition between the sub-Alfvénic and super-Alfvénic regimes (Figure 3 ). The stellar wind conditions corresponding to these simulations are listed in Table 3 . Figure 3. Magnetospheric structure of a planet situated at the orbit of TRAPPIST-1e. The planet is represented by a magenta isosurface, and it was modeled to have a magnetic field strength of 0.3 G and an evaporative outflow with a temperature of 10 4 K, escape velocity 10 km s −1 , and density of 4 × 10 8 amu cm −3 . The stellar wind flows from the positive x -axis. The solutions are for the sub-Alfvénic (top panels), transition (bottom left), and super-Alfvénic (bottom right) stellar wind cases. The stellar wind conditions were extracted from a 3D MHD simulation of TRAPPIST-1a by Garraffo et al. ( 2017 ). The color scale shows an equatorial projection (plane z = 0) of the particle number density. Planetary magnetic field lines connected to the planet are shown in white, while stellar field lines are shown in cyan. The planetary outflow is denoted by velocity streamlines (black with arrows). Note that the lines transition in color as they pass through the equatorial plane. The motion of the planet is toward the positive y -axis. All of the stellar wind conditions experienced by TRAPPIST-1e are much more extreme than the solar wind conditions experienced by Earth. In the region surrounding the planets, the stellar wind speeds reach close to 1400 km s −1 and plasma densities reach 10 3 –10 5 times the solar value at 1 au (Garraffo et al. 2017 ). We consider the effect of these strong stellar wind conditions on a planetary outflow in Figure 3 . In each case, the planet is represented by a magenta isosurface at the center of the GM domain. The z = 0 plane of number density shows the planetary outflow, which is strongly dependent on the stellar wind conditions and therefore varies substantially between the different cases. Under all four stellar wind regimes, the planetary magnetic field lines are strongly advected by the wind, causing changes in the magnetospheric configuration, which results in an asymmetric outflow in three dimensions. The shape of the planet’s outflow is strongly influenced by the direction and relative magnitudes of the components of both the magnetic field and velocity of the incoming stellar wind. By comparing cases 1 and 2, where the planet is within the sub-Alfvénic region, the stellar wind components (shown in Table 3 ) are broadly similar apart from the y and z magnetic field components. As can be seen in Figure 3 , this produces wholly different magnetospheric