On NASA’s Gemini XII flight, the computer docking system failed and Buzz Aldrin (who did his doctoral thesis at MIT on line-of-sight orbital mechanics) successfully calculated the docking trajectory using a sextant and a slide rule. – WTF Fun Facts
Source: https://www.nasa.gov/feature/gemini-xii-crew-masters-the-challenges-of-spacewalks
WTF Fun Fact – NASA Sextant And Slide Rule

Because Buzz Aldrin was (and is) a freaking bada$$.
Old school is still school.
Trying to learn some Celestial navigation great fun fact thank you