SortStack #1240 — 2029-10-31

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 crawling slug 30 m/h

   A slug glides on a ribbon of self-made slime, which lets it cross even a razor's edge unharmed.

3. A person walking 5 km/h

   The average person takes around 7,000 steps a day, walking the equivalent of several times around Earth in a lifetime.

4. A peregrine falcon in a dive 410 km/h

   The peregrine is the fastest animal on Earth, diving so fast it has baffles in its nostrils to breathe.

5. A tsunami across the open ocean 800 km/h

   In deep water a tsunami is barely a ripple, racing as fast as a jet before rearing up near the shore.

6. NASA's Parker Solar Probe 692K km/h

   The fastest human-made object ever, it slingshots around the Sun, dipping into the star's blazing outer atmosphere.

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