SortStack #3308 — 2035-06-30

By duration · Order from shortest to longest.

1. 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.

2. a-ha's 'Take On Me' 3.8 min

   The Norwegian band recorded it three times before it became a hit — the famous pencil-sketch video took 16 weeks of rotoscoping by hand.

3. Cooking a perfect soft-boiled egg 4.5 min

   At high altitude it takes noticeably longer — water boils below 100°C up a mountain, which is why mountaineers complain about their eggs.

4. NASA's Perseverance rover travelling from Earth to Mars 203 days

   The 480-million-km cruise ended with the 'seven minutes of terror' landing — and the rover carried a small helicopter, Ingenuity, strapped to its belly.

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. A photon's journey from the Sun's core to its surface 170K years

   Energy ricochets through the dense interior for on the order of 100,000 years — then crosses the void to Earth in barely eight minutes.

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