First electro-optical astro-inertial system was developed for the Northrop SM-62 Snark, starting in the late 1940s. Airborne star acquisition and tracking was demonstrated around 1952. Snark of course was cancelled but Northrop built the Blackbird's system and that for the B-2. Kollsman developed an astro-tracker integrated into the B-58's NAS, and the Skybolt missile had one built into the pylon to update the INS immediately before launch. There is a Snark system in the Udvar-Hazy.
