1. On March 20, 1961, the Minuteman I intercontinental ballistic missile was successfully launched from Ellsworth Air Force Base. The missile played a crucial role in the country's Cold War defense strategy.

2. The University of South Dakota held its first classes on March 20, 1882. The university has since grown into a major educational institution with over 10,000 students.

3. March 20, 1972, marks the beginning of the historic Black Hills flood. Heavy rainfall caused widespread damage and devastation throughout the region, forcing thousands of people to evacuate and resulting in millions of dollars in damages.

4. In 1957, the South Dakota Legislature designated the State Flower as the Pasque Flower. The flower blooms primarily in the spring, making March 20 a particularly significant day for the state's official flower.

5. The first ever South Dakota Science and Technology Forum was held on March 20, 2014, in Rapid City. The forum brought together scientists, researchers, and entrepreneurs from around the state to discuss important scientific advancements and promote innovation in South Dakota.