Instagram was launched and gained 25,000 users on its first day.
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The 51 Pegasi b planet was discovered. It was the first discovered exoplanet around a sun-like star.
The drama romance film 'Days of Heaven' by Terrence Malick was released.
'The Jazz Singer' was released. It was the first motion picture with pre-recorded dialogue, revolutionizing the movie industry.
The Moulin Rouge cabaret opened its doors in Paris for the first time.
The American epic historical drama movie 'Spartacus' premiered in New York City.