If you attended school in Colorado, there is a good chance you've learned a great deal about the history of the state. Alferd Packer. Pikes Peak. Bent's Fork... you know it all. However, I am willing to bet you've never heard of Mike the Headless Chicken, the story of how Dinger the Dinosaur came to be, or the South Cañon Number 1 Coal Mine fire. Am I right? Read on to learn more about these forgotten moments in Colorado history:

1. On Jan. 7, 2011, Gov. Bill Ritter signed a posthumous pardon for Joseph "Joe" Arridy; a 23-year-old mentally handicapped man who was wrongfully convicted and killed for the rape and murder of a Colorado woman in 1939.

Arridy has been referred to as the "happiest man on death row," and is said to have only had the understanding of a 6-year-old.

2. In 1999, scientists at the Commerce Department's National Institute of Standards and Technology in Boulder developed an atomic clock so accurate that it will neither gain nor lose a second in nearly 20 million years.

3. The first ever arrest for possession and selling of marijuana took place in Denver in 1937.

If they could see us now...

4. Former Colorado Governor Ralph L. Carr destroyed his own political career after speaking out for both the racial tolerance and protection of the constitutional rights of Japanese Americans following Pearl Harbor.

5. In 1914, 19 men, women, and children were brutally killed by the Colorado Fuel and Iron Company when they attempted to join the United Mine Workersof America.

Colorado Fuel and Iron is said to have hired company guards, thugs, and militiamen to either shoot or set fire to the strikers and their families.

6. Have you ever wondered why the Rockies mascot is a dinosaur? It turns out that construction workers found numerous fossils while laying the ground for Coors Field, including a 7-foot-long, 1,000-pound triceratops skull.

7. The statues handed out at the Grammy Awards are made every year by a Colorado man named John Billings.

8. The South Cañon Number 1 Coal Mine near Glenwood Springs has been on fire since 1910.

No joke.

9. After a botched beheading near Fruita, Mike the Headless Chicken became a sideshow sensation who earned close to $4,500 per month ($47,700 today).

The headless chicken lived for nearly 18 months without his head and ate a diet of milk, water, and small grains of corn.

10. Author Hunter S. Thompson ran for sheriff of Pitkin County in 1970 with promises of decriminalizing personal drug use, turning streets into grassy pedestrian malls, and banning tall buildings that take away the view of the mountains.

He lost.

11. The now-extinct Rocky Mountain Locust used to swarm together in packs of trillions, which was enough to cover the entire state of Colorado.

Be honest: How many of these did you know?