1. Birth of Nobel Prize Winning Physicist David J. Wineland: On August 20, 1944, David J. Wineland was born in Wauwatosa, Wisconsin. He would eventually move to Colorado and become a professor at the University of Colorado Boulder. In 2012, he was awarded the Nobel Prize in Physics for his work in quantum mechanics.

2. Construction of the Moffat Tunnel: On August 20, 1923, construction began on the Moffat Tunnel in Colorado. The tunnel, which stretches over 6 miles, connects east and west Colorado and was used by the Denver, Northwestern and Pacific Railway. It was a significant engineering feat and helped spur economic development in the state.

3. Colorado Governor Samuel Elbert Resigns: On August 20, 1878, Colorado Governor Samuel Elbert resigned from office. He had served two terms as governor and was known for supporting the rights of miners and improving the state's infrastructure.

4. Tragic Plane Crash in Durango: On August 20, 1947, a United Airlines plane crashed near Durango, Colorado, killing all 11 passengers and crew members on board. The cause of the crash was never determined, but it was one of the deadliest aviation disasters in Colorado history.

5. Colorado Native Becomes First Female Amputee to Summit Mount Rainier: On August 20, 2010, Colorado native Bonnie St. John became the first female amputee to summit Mount Rainier, one of the tallest peaks in the United States. St. John had her right leg amputated at age 5 and has become an accomplished athlete, author, and motivational speaker.