Pomegranate How Long is a Second?

Clocks connect us to our universe. From the upright stick whose shadow traced the hours to the pendulums that imitated Galileo’s swaying chandelier, the tools used early on to slice up the day measured the motion of Earth. More recently the task of measuring time has been assigned to atoms: the newest generation of atomic clocks is accurate to within one second in 80 million years. The 48 cards in this deck examine some of the challenges involved in modern timekeeping, from creating wristwatc…