Microsoft released the Windows 7 operating system.
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The US gross national debt exceeded $1 trillion.
The Royal Observatory in Greenwich, UK, was adopted as the world's Prime Meridian.
In-N-Out Burger opened its first restaurant in Baldwin Park, Los Angeles, US.
The Marvel superhero movie 'Thor: The Dark World' premiered in London, UK.
The world's first recorded parachute jump occurred from 3,300 feet (1,000 m) above Paris.