NASA's Farside Seismic Suite (FSS) is assembled in a clean room at the agency's Jet Propulsion Laboratory in Southern California in November 2023. Two sensitive seismometers packaged in the suite's cube-within-a-cube structure will gather NASA's first seismic data from the Moon in nearly 50 years and take the first-ever seismic measurements from the Moon's far side. FSS will operate continuously for at least 4½ months, working through the long, cold lunar nights. Seen here is the inner cube structure, with the suite's large battery at rear. The gold, puck-shaped device at left is the Short Period sensor, or SP, which measures motion in three directions using sensors etched into a trio of square silicon chips, each about 1 inch (25 millimeters) wide. At right, within the silver cylindrical enclosure, is the Very Broadband seismometer, or VBB, the most sensitive seismometer ever built for use in space exploration. It can detect ground motions smaller than the size of a single hydrogen atom, measuring up-and-down movement using a pendulum held in place by a spring. Constructed as a backup instrument (a "flight spare") for NASA's InSight Mars lander by the French space agency, CNES (Centre National d'Études Spatiales), the VBB was slightly modified and packaged in a new enclosure for lunar use. The suite's computer and electronics are packed alongside the battery and seismometers. After being encased in insulation, this inner cube was suspended within a protective outer cube, which was in turn covered with a shiny insulating blanket. https://photojournal.jpl.nasa.gov/catalog/PIA26300