For decades, scientists have believed there to be a fairly well-defined boundary at the edges of our solar system, a region where the sun appears only slightly brighter than the rest of the spangled heavens. But as they sail through the blackness, humanity’s most-traveled spacecraft, the Voyager probes, have learned the lines are anything but clear. The edge of the solar system may not be a smooth edge at all, but a turbulent moat of roiling magnetic bubbles.
The "termination shock" sounds like the stuff science fiction movies are made of. In reality, it marks the boundary between our solar system and interstellar space. The invisible "shock" forms as our sun's solar winds begin to encounter the gases and magnetic fields of outer space, which slows the winds down abruptly.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.