Passage: USA-193, also known as NRO launch 21 (NROL-21 or simply L-21), was a U.S. military reconnaissance satellite (radar imaging) launched on 14 December 2006. It was the first launch conducted by the United Launch Alliance. Owned by the National Reconnaissance Office (NRO), the craft's precise function and purpose were classified.

Question: When was USA-193 launched?
14 December 2006