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Some entities operate "unacknowledged" satellites, often for secretive military or intelligence purposes, visible from Earth with the right equipment even without official acknowledgment. Notably, amateur astronomers have a role in monitoring these objects. For example, Scott Tilly, a dedicated satellite tracker based in British Columbia, recently discovered a decommissioned U.S. military satellite, LES 5, launched in 1967 and decommissioned in 1972. Tilly is part of an informal international network called See-Sat-L, which encourages amateur astronomers worldwide to document space objects.