1. Maine became a state on August 15, 1820: The state of Maine officially joined the Union as the 23rd state on August 15, 1820. Prior to its admission, Maine was part of Massachusetts.

2. The Great Fire of 1866: On August 15, 1866, a devastating fire broke out in Portland, Maine, destroying a large portion of the city's business district. The fire, which lasted for 17 hours, caused millions of dollars in damage and left over 10,000 people homeless.

3. The Brunswick Naval Air Station was established on August 15, 1943: During World War II, the United States Navy established a naval air station in Brunswick, Maine. The air station played a critical role in the war effort, providing support for anti-submarine warfare operations.

4. Maine's first hydroelectric station was dedicated on August 15, 1893: On August 15, 1893, the first hydroelectric power plant in Maine was officially dedicated. The power plant was located in the town of Skowhegan and provided electricity to a number of local businesses and residences.

5. The Allagash Abductions took place on August 15, 1976: On August 15, 1976, four men camping in the Allagash Wilderness in Maine reported being abducted by aliens. The men claimed to have been taken aboard a spacecraft and subjected to medical experiments before being released several hours later. The incident remains one of the most famous alleged alien abductions in history.