1. In 1865, Congress approved the Thirteenth Amendment to the United States Constitution, which abolished slavery and involuntary servitude, and Oregon became the eighth state to ratify the amendment on January 31 of the same year.

2. On January 31, 1918, Oregon's Governor James Withycombe passed away suddenly, only two days after delivering his annual message to the state legislature. Withycombe was the first Oregon governor to die in office, and his sudden death shocked the state's political establishment.

3. In 1945, the U.S. Army Signal Corps established Crater Lake National Park's first weather station on Mount Scott, Oregon. The station provided important meteorological data for the region, including snow depth, wind speed, and temperature, and helped the park better understand its unique weather patterns and challenges.

4. On January 31, 1958, the first successful artificial satellite, Explorer 1, was launched into space by the United States. The satellite carried instruments designed by James Van Allen, a professor at the University of Iowa, which discovered the radiation belts surrounding the Earth, now known as the Van Allen belts.

5. In 2002, Oregon's Mount Hood erupted unexpectedly, prompting the evacuation of hundreds of residents and tourists in the area. While the eruption was relatively small, it served as a reminder of the volcanic activity that lies beneath the surface of the Pacific Northwest region, and the need to be prepared for future events.