SortStack #659 — 2028-03-29

By speed · Order from slowest to fastest.

1. The creep of a mountain glacier 175320 mm/year

   Glaciers flow downhill under their own weight like very slow rivers of ice, grinding valleys as they go.

2. A red fox 51 km/h

   Foxes may use Earth's magnetic field to aim their pounces, lining up on prey hidden under snow.

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 leaping blue marlin 108 km/h

   Marlins can change colour when excited, their stripes lighting up electric blue during a hunt.

5. A speeding hovercraft 145 km/h

   A hovercraft floats on a cushion of trapped air, gliding equally well over water, land, ice and mud.

6. A record badminton smash 565 km/h

   The shuttlecock is the fastest object in any racket sport, though it decelerates almost as quickly as it launches.

← All puzzles · Play today’s SortStack