Galileo Galilei discovered Callisto, the fourth moon of Jupiter.
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A meteorite that landed in Australia in the 1960s revealed stardust up to 7 billion years old.
German composer Richard Wagner completed 'Parsifal' – one of his most famous operas.
Nine thousand scientists from 43 nations signed a petition to ban nuclear testing.
Avezzano earthquake claimed 30,000 lives in Italy.
Instruments used to observe Venus found two-thirds of the planet's southern hemisphere brightened after aerosols were triggered on an 'astronomical' scale.
