Rebecca Lee Crumpler became the first African American female physician.
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At 340 days, Astronaut Scott Kelly completed the longest single mission aboard the International Space Station.
The Yellowstone National Park Protection Act went into law, making it the first National Park in the world.
Ohio became the 17th state to join the United States of America.
Nebraska became the 37th state to join the United States of America.
Captain America issue #1 comic was published by Timely Comics (which later became Marvel).