1. On January 16, 1920, the 18th amendment to the US Constitution went into effect, ushering in the era of Prohibition. This ban on the sale, production, and transportation of alcohol had a major impact on Pennsylvania, which was home to a sizable brewing industry.

2. January 16 is also the birthday of Dian Fossey, the renowned primatologist and conservationist who spent many years studying and protecting mountain gorillas in Rwanda. Fossey was born in San Francisco in 1932, but spent much of her adult life in Pennsylvania, where she earned a doctorate in zoology from the University of Cambridge.

3. In 1991, Pittsburgh native Dr. Judith Resnik was tragically killed in the Space Shuttle Challenger explosion. Resnik was an accomplished astronaut and engineer who had previously flown on the maiden voyage of the Space Shuttle Discovery. She was the second American woman to travel to space.

4. On January 16, 1883, the Pendleton Act was signed into law by President Chester A. Arthur. This legislation established the modern civil service system in the United States, and aimed to reduce corruption and nepotism in federal government hiring practices.

5. January 16 is also the starting date of the Great Molasses Flood of 1919. In this tragic incident, a storage tank holding 2.3 million gallons of molasses burst in the North End neighborhood of Boston, causing a wave of syrupy goo to rush through the streets and killing 21 people. While this event did not take place in Pennsylvania, the commonwealth felt its effects - the Purity Distilling Company, which owned the tank, had a large presence in Philadelphia at the time.