It was 63 years ago today that the United States detonated the very first atomic bomb. Three weeks later, the only two A-bombs dropped in warfare destroyed Hiroshima and Nagasaki, Japan. Many nuclear -- and thermonuclear -- bombs have been tested since. Here are some images.
Operation Upshot-Knothole, conducted at the Nevada Proving Ground between March 17 and June 4, 1953, consisted of 11 atmospheric tests: three airdrops, seven tower tests and one airburst. Upshot-Knothole involved the testing of new theories, using both fission and fusion devices.
House No. 1, located 3,500 feet from ground zero, was completely destroyed on the first day of testing. The elapsed time from the first picture to the last was 2⅔ seconds. The camera was completely enclosed in a 2-inch lead sheath as a protection against radiation. The only source of light was that from the detonation. Frame No. 1 (upper left) shows the house lighted by the blast. Frame No. 2 (upper right) shows the house on fire.: Courtesy National Nuclear Security Administration/Nevada Site Office
"The island of Elugelab is missing!" President Truman heard this short report from Gordon Dean, chairman of the Atomic Energy Commission, following the "Mike shot," conducted as part of Operation Ivy. Mike, which delivered 10.4 megatons, was the first full-fledged hydrogen bomb to be detonated. It vaporized the small islet of Elugelab in the Eniwetok Atoll.: Courtesy National Nuclear Security Administration/Nevada Site Office
Official observers view the Wasp Prime air drop at the Nevada Test Site on March 29, 1955. It was the second detonation of the day. Apple-1 came five hours earlier, marking the first time two nuclear devices were set off on the same day.
Operation Teapot consisted of 14 shots, or detonations, conducted during the first half of 1955. Teapot's objective was to evaluate the tactical applications of a variety of devices for possible inclusion in the nuclear-weapons stockpile, as well as to study civil-defense requirements.: Courtesy National Nuclear Security Administration/Nevada Site Office
This base camp near Los Alamos, New Mexico, supported Project Trinity. The first atomic bomb in history was successfully tested nearby in July 1945. Trinity represented the culmination of the Manhattan Project, the U.S. effort to build and detonate an atomic device. Within 24 days of this test, the Japanese cities of Hiroshima and Nagasaki were laid waste by atomic bombs.: Photo: Corbis
The first atomic bomb is readied for testing near Alamogordo, New Mexico, in July 1945.: Photo: Corbis
J. Robert Oppenheimer, in white hat, and Gen. Leslie Groves, military commander of the Manhattan Project, examine the twisted wreckage that is all that remains of a 100-foot tower, winch and shack that held the first nuclear weapon before its July 16, 1945, detonation. On the far right is Victor Weisskopf of the Manhattan Project's Theoretical Division.: Photo: Nagasaki Atomic Bomb Museum/Corbis
The exact moment of detonation at Nagasaki is captured in this remarkable photograph. Notice the three people in the foreground, as yet unaware that anything has happened. The destruction of Nagasaki followed that of Hiroshima by three days and compelled Japan to surrender, ending World War II.: Photo: AP/Kyodo News/Hirofumi Kimata
Asa Takii, 114, Japan's oldest woman, seen in this June 1998 picture, was a survivor of the Hiroshima bombing. The blast killed her husband and family, but Takii survived despite being trapped in the rubble of her home for days before rescue came. She died at a nursing home at Kurahashi Island near Hiroshima on July 31, 1998.: Photo: Corbis
July 1, 1946, in the Marshall Islands: A mushroom cloud erupts in the North Pacific Ocean over the Bikini Lagoon during the first of the two detonations of Operation Crossroads. The series studied the effects of nuclear radiation on large ships, and the United States assembled a fleet of 90 obsolete naval vessels, including a few captured German and Japanese warships, for the test. Several ships can be seen here, silhouetted against the blast.