An Olympic gold medal is almost 99% silver.

The first-place medal is actually 550 grams of silver covered with a thin layer of gold (6 grams)! A silver medal is far more authentic - 509 grams of silver and 41 grams of copper. The bronze medal is composed of mostly copper, with some zinc and tin mixed in. And approximately how much are all these precious medals worth, you ask? The gold - $494, the silver - $260, and the bronze...$3!

A man survived both the Hiroshima and Nagasaki atomic bombs.

Unfortunately, this remarkable individual passed away earlier this year at the age of 93. Tsutomu Yamaguchi is the only individual to be recognized as having survived both atomic bombs during World War II. Back in 1945, Yamaguchi was on a business trip to Hiroshima when the first bomb dropped on August 6th. The blast caused him to go blind and deaf temporarily, and had serious burns across his body.

He returned home to Nagasaki three days later to a second atomic bomb less than 2 miles from his house! The explosions caused him to go completely deaf in his left ear. In later years, he suffered from complications such as leukemia, cataracts, and other bomb and radiation-related illnesses. Yamaguchi was one of 200,000 Japanese citizens recognized as having been affected by either of the bombs.

Before working on Avatar, actor Sam Worthington was living in his car!

He was already an actor in Australia at the time, but Worthington was living in his car prior to meeting James Cameron and landing the Avatar role. Worthington also has worked in the past as a bricklayer. Definitely an unusual background for someone in one of the most successful movies of all time.