Manhole Memes

During the 1957 Pascal-B nuclear test, a 900kg steel cap covering a test shaft was blasted off at an estimated 66 km/s (5x escape velocity). While historians calmly credit Sputnik as humanity's first space object, nuclear physicists are having an existential crisis knowing a random manhole cover might have been yeeted into interstellar space years earlier. The cover was never found—probably because it's somewhere between here and Alpha Centauri by now. Just another day in Cold War physics: turning infrastructure into accidental spacecraft since 1957.