The NOAA Commissioned Officer Corps (NOAA Corps) is the smallest of the eight U.S. federal uniformed services, operating under the Department of Commerce and comprised solely of technically trained commissioned officers—with no enlisted or warrant ranks, a distinction shared only with the U.S. Public Health Service. Its primary mission is to monitor oceanic and atmospheric conditions, with officers operating NOAA ships and aircraft, managing research projects, and conducting diving operations. While the service officially dates its establishment to the creation of the U.S. Coast and Geodetic Survey Corps on May 22, 1917, its roots stretch back to 1807 when President Thomas Jefferson founded the Survey of the Coast, which played a crucial role during the Civil War after Army and Navy officers were withdrawn. The corps evolved through name changes, becoming the ESSA Corps in 1965 and finally the NOAA Corps in 1970. Today, with over 300 officers trained in disciplines like oceanography and meteorology, the corps also serves as a reserve of skilled scientists who can be integrated into the U.S. Armed Forces during times of war.