A 6.9 earthquake in Spitak, Armenia, killed 25,000-50,000 people and left up to 500,000 homeless.
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Delaware became the first state to ratify the US constitution.
One of America's oldest documented highways was completed on this day in Connecticut, USA.
Coca-Cola was named the world's largest plastic polluter by the charity 'Break Free From Plastic.'
The Royal Opera House opened at Covent Garden, London, England.
Apollo 17 launched the final manned lunar landing mission, during which the crew took the famous 'blue marble' photo of the entire Earth.
