1. In 1787, Pennsylvania became the second state to ratify the United States Constitution. This historic event took place on February 21, making it an important day for Pennsylvania and the entire country.

2. In 1878, the first telephone exchange in Pennsylvania was established in Pittsburgh. This technological breakthrough allowed people to communicate with each other in a new and more efficient way.

3. On February 21, 1965, civil rights leader Malcolm X was assassinated while speaking at the Audubon Ballroom in New York City. While this event did not take place in Pennsylvania, it had a profound impact on the civil rights movement and the fight for racial equality throughout the country.

4. In 1987, Pennsylvania treasurer Budd Dwyer infamously committed suicide during a press conference. This shocking and tragic event captured national attention and raised questions about mental health and the pressures of public office.

5. On February 21, 2014, an explosion occurred at the natural gas processing plant in Monroe County, Pennsylvania, injuring four workers and causing extensive damage to the facility. This event highlighted the risks associated with natural gas production and the need for safety measures to protect workers and nearby communities.