SortStack #561 — 2027-12-22

By speed · Order from slowest to fastest.

1. The drift of a tectonic plate 21.9 mm/year

   Plates move about as fast as your fingernails grow, yet over millions of years they have rearranged whole continents.

2. A wild boar running 45 km/h

   Wild boars are spreading across the globe, rooting up so much soil they reshape entire ecosystems.

3. A bottlenose dolphin 60 km/h

   Dolphins sleep with half their brain at a time, keeping one eye open to breathe and watch for danger.

4. A record tennis serve 270 km/h

   The fastest serves leave the racket so quickly the returner must react before the ball has even crossed the net.

5. An IndyCar on an oval 390 km/h

   IndyCars on superspeedways run flat-out for hours, with drivers enduring forces that strain the neck lap after lap.

6. A top-fuel dragster 540 km/h

   A dragster covers a quarter mile in under four seconds, accelerating harder than a fighter jet off a carrier.

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