A week after time ran out on their first attempt, NASA astronaut Anil Menon and ESA's Sophie Adenot returned to the exterior of the International Space Station on August 25th to finish installing a communications antenna that keeps the orbiting laboratory in voice with Earth. Their work — methodical, demanding, and largely invisible to the public — represents the 283rd spacewalk in a quarter-century of continuous human presence aboard the station. Adenot, the first French woman to walk in space, and Menon, on his third extravehicular excursion, remind us that the frontier is maintained not by