On This Day

What Happened on September 21, 2017

Day of the Week: Thursday

Historical Events

  • Andre Ward, unified light heavyweight champion and world’s top pound-for-pound boxer, announces his retirement

Historic DiscoveryBrainless Jellyfish that Sleeps

Discovery of the first brainless animal that sleeps, the jellyfish Cassiopea, research published in "Current Biology" by Caltech scientists
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The Cassiopea jellyfish spends most of its life resting upside down while underwater
The Cassiopea jellyfish spends most of its life resting upside down while underwater

Famous Deaths

  • Liliane de Bettencourt, French heir to L'Oreal and richest woman in the world from 2016, dies at 94