For the first time, the U.S. government levied an income tax.
The cornerstone for the Statue of Liberty was laid on Bedloe's Island.
The first electric traffic lights were installed in Cleveland, Ohio.
Marilyn Monroe died.
The U.S. space probe Mariner 7 transmitted pictures of Mars.
The gun turret of the Civil War ironclad USS Monitor was raised from the ocean floor.
The plutonium-powered rover Curiosity successfully lands on Mars. Larger than earlier rovers, Curiosity will spend two years examining the land, looking for evidence that conditions on Mars are fit for life.