By Sid Perkins
In the predawn hours of July 16, 1945, an explosion rocked the desert of central New Mexico. The flash of light from the blast lit the sky statewide, and residents felt the shock wave as far as 160 miles away. U.S. Army officials first said a munitions storage area at the Alamogordo Bombing Range had accidentally exploded. The truth was revealed less than a month later, when U.S. planes dropped atomic bombs on Hiroshima and Nagasaki and ended World War II.
The 19-kiloton blast that had shaken residents of the American Southwest–the results of the 3-year, secret Manhattan Project–was the world’s first nuclear test.