SortStack #669 — 2028-04-08

By duration · Order from shortest to longest.

1. A car airbag inflating after a crash 30 ms

   The bag must fully inflate before your head arrives — roughly ten times faster than the blink of an eye, driven by a controlled chemical explosion.

2. One swing of a grandfather clock's pendulum 1 sec

   A pendulum about one metre long swings in almost exactly one second — a coincidence so neat it was once proposed as the definition of the metre.

3. Charles Lindbergh's solo flight from New York to Paris 33.5 h

   Lindbergh went without sleep so long he reported hallucinating ghostly figures in the cockpit somewhere over the Atlantic.

4. The Islamic holy month of Ramadan 29.5 days

   Because it follows the lunar calendar, Ramadan drifts about 11 days earlier each year — cycling through every season over 33 years.

5. The main construction of Notre-Dame de Paris 97 years

   The medieval build ran from 1163 to 1260 — yet after the 2019 fire, the cathedral was restored and reopened in just five years.

6. The Holy Roman Empire, from Otto the Great to its dissolution 844 years

   Voltaire quipped it was 'neither holy, nor Roman, nor an empire' — yet it lasted 844 years before Napoleon finished it off in 1806.

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