Alpha radiation is a type of energy released when certain radioactive elements decay or break down. For example, uranium and thorium are two radioactive elements found naturally in the earthâs crust. Over billions of years, these two elements slowly change form and produce âdecay productsâ such as radium and radon.
Before the big race, a two week Kentucky Derby Festival takes place with events for the whole family. Then, as usual, the race will take place on the first Saturday in May 2016. On the big day, the contenders will line-up to race around a 1.25 mile track.
The Kentucky Derby was first run at 11â2 miles (2.4 kilometres), the same distance as the Epsom Derby. The distance was changed in 1896 to its current 11â4 miles (2.0 kilometres). On May 17, 1875, in front of an estimated crowd of 10,000 people, a field of 15 three-year-old horses contested the first Derby.