SortStack #687 — 2028-04-26

By speed · Order from slowest to fastest.

1. The growth of a cave stalactite 0.1 mm/year

   Most stalactites lengthen by less than a tenth of a millimetre a year, dripping mineral by mineral over millennia.

2. 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.

3. A swimming seahorse 1.5 m/h

   The dwarf seahorse is the slowest fish on record, fluttering a tiny fin dozens of times a second to barely move.

4. A wild boar running 45 km/h

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

5. An arrow loosed from a bow 230 km/h

   A modern compound bow uses pulleys to store huge energy, launching an arrow with deadly accuracy.

6. The International Space Station in orbit 28K km/h

   The station circles Earth so fast its crew sees about 16 sunrises and sunsets every single day.

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