The SR-71’s star tracker was so sensitive it could track stars during the day. https://theaviationgeekclub.com/the-sr-71-blackbird-astro-nav-system-aka-r2-d2-w

The SR-71’s star tracker was so sensitive it could track stars during the day. https://theaviationgeekclub.com/the-sr-71-blackbird-astro-nav-system-aka-r2-d2-worked-by-tracking-the-stars-and-was-so-powerful-that-it-could-see-the-stars-even-in-daylight/ https://theaviationgeekclub.com/the-sr-71-blackbird-astro-na...