SortStack #11 — 2026-06-20

By duration · Order from shortest to longest.

1. A camera speedlight flash firing at full power 1 ms

   At low power settings, flash bursts get even shorter — down to around 1/30,000 of a second, fast enough to freeze a bursting balloon mid-pop.

2. One full revolution of a helicopter's main rotor 150 ms

   Main rotors spin at only a few hundred rpm, but the blade tips travel so fast they approach the speed of sound — the source of that thudding chop.

3. A lightning flash from start to finish 198 ms

   What looks like one bolt is usually several return strokes in a row, heating the air to around 30,000°C — five times hotter than the Sun's surface.

4. The Woodstock music festival of 1969 2.8 days

   Billed as '3 days of peace & music', it overran badly — Jimi Hendrix closed at 9 am on Monday to a field mostly littered with sleeping bags.

5. The Wimbledon tennis championships 14 days

   The tournament's famous rest day, the 'Middle Sunday', was only abolished in 2022 after 145 years of tradition.

6. The Cold War 43.9 years

   Historians call it 'the long peace' — the superpowers never fought each other directly, but proxy wars touched nearly every continent.

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