SortStack #386 — 2027-06-30

By speed · Order from slowest to fastest.

1. The growth of human hair 175.3 mm/year

   Scalp hair grows roughly 1.25 centimetres a month, so a single strand reaching your shoulders is years old.

2. A polar bear running 40 km/h

   A polar bear's skin is actually black under its clear, hollow fur, helping it soak up the Arctic sun.

3. A racing greyhound 76 km/h

   Greyhounds reach their top speed in just a few strides and spend much of a sprint completely airborne.

4. A galloping wildebeest 92 km/h

   Over a million wildebeest migrate in a giant loop each year, a journey so vast it is visible from space.

5. The winds of a violent tornado 480 km/h

   The strongest tornado winds ever measured can strip bark from trees and drive straw into solid wood.

6. The X-15 rocket plane 7.3K km/h

   The X-15 flew to the edge of space, and several of its pilots earned astronaut wings without leaving a runway.

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