An electrostatic analyzer was a piece of advanced sensor technology aboard NASA's Ranger Block I space probes when they were launched in the mid-20th century.
A schematic of the Ranger spacecraft depicting the location of the cosmic dust detector was stored in the USS Enterprise's library computer database. This database was accessed by the Talosians in 2254. (TOS: "The Cage")
The schematic of the Ranger spacecraft was from the archives of the National Aeronautics and Space Administration - Jet Propulsion Laboratory.