SortStack #221 — 2027-01-16

By duration · Order from shortest to longest.

1. The average adult's actual night of sleep 6.8 h

   Smartphone-tracking studies put the global average well under the recommended eight hours — and humans sleep less than virtually any other primate.

2. A tiger's pregnancy 105 days

   Cubs are born blind and helpless at around a kilogram — yet within two years they're apex predators ten times their mother's litter weight.

3. NASA's Perseverance rover travelling from Earth to Mars 203 days

   The 480-million-km cruise ended with the 'seven minutes of terror' landing — and the rover carried a small helicopter, Ingenuity, strapped to its belly.

4. Voyager 1's journey from launch to interstellar space 35 years

   It carries a golden record with greetings in 55 languages and Chuck Berry — and it still phones home daily on a 1970s 8-track-era computer.

5. The time since a human last stood on the Moon 53.4 years

   Gene Cernan traced his daughter's initials in the dust in December 1972 — no boots have touched the surface since.

6. The age of the Lascaux cave paintings 17K years

   Four teenagers and a dog named Robot found the caves in 1940 — visitor breath damaged the art so badly that today tourists see a replica.

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