- Oh-My-God particle (Wikipedia)
The Oh-My-God particle was an ultra-high-energy cosmic ray detected on 15 October 1991 by the Fly’s Eye camera in Dugway Proving Ground, Utah, United States. As of 2023, it is the highest-energy cosmic ray ever observed. Its energy was estimated as (3.2±0.9)×1020 eV (320 exa-eV). The particle’s energy was unexpected and called into question prevailing theories about the origin and propagation of cosmic rays.
- Lock and Dam No. 7 (Wikipedia)
Lock and Dam No. 7 is a lock and dam located on the Upper Mississippi River at river mile 702.5 near the cities of La Crescent, Minnesota and Onalaska, Wisconsin. It forms pool 7 and Lake Onalaska. The facility was constructed in the mid-1930s and placed in operation in April 1937. It underwent major rehabilitation from 1989 through 2002. The lock and dam are owned and operated by the St. Paul District of the United States Army Corps of Engineers-Mississippi Valley Division.
