Three astronauts, Richard J. Hieb, Thomas D. Akers, and Pierre J. Thuot, simultaneously walked in space for the first time.
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The first four-engine aircraft was built and flown by Igor Sikorsky.
Apple released its Macintosh System 7.0.
Brazil introduced the Golden Law (Lei Áurea), signed by the Princess Imperial of Brazil, which abolished all forms of slavery.
Winston Churchill made his famous speech to the House of Commons.
OpenAI's newest version of ChatGPT, GPT-4 Omni (GPT-4o), went live.