The U.S. Army Corps, under the joint control of the U.S. Atomic Energy Commission and the Department of Defense, could see the towering mushroom cloud of an atomic bomb exploding during a maneuver at the Nevada Nuclear Test Site in the fall of 1951 from a distance of about 160 kilometers. Numerous Army personnel from the nuclear test were cheering as they witnessed the event from a distance. The first nuclear test in history was conducted on July 16, 1945 in Ala mode, New Mexico, followed by a nuclear test in the Marshall Islands on July 1, 1946, and a nuclear test in Nevada on January 27, 1951.
The Nevada Test Site (NTS) is a nuclear test site managed by the United States Department of Energy. It is located in the Nevada Desert in the U.S. state of Nevada, about 105 km northwest of Las Vegas, in a desert and mountainous region. 1,760 square kilometers of Nellis Air Force Base in southern Nevada was approved by the Truman Administration as the Nevada Test Site on December 18, 1950. In August 2010, the official name was changed to the Nevada National Security Site (NNSS). In the past, atmospheric nuclear tests and, since September 1961, underground nuclear tests have been conducted at the site, but currently subcritical nuclear tests are being conducted.
Mushroom clouds from the atmospheric tests could be seen at a distance of about 160kmm. In the 1950s and early 1960s, many tourists could see the emission and the mushroom cloud from their hotel windows. Hotels advertised these sights. Some casinos held "dawn parties" and created atomic-themed cocktails to encourage visitors to view the tests. Calendars around the city also advertised the time of the explosion and the best spots to watch for flashes, lights, and mushroom clouds.
The radioactivity produced by the nuclear explosion was suspended by the prevailing westerly winds to the states of St. George and southern Utah. In particular, atmospheric nuclear tests released large amounts of radioactive iodine into the atmosphere. The exposure to this radioactivity led to a marked increase in the incidence of malignant neoplasms of thyroid, breast, prostate, and digestive cancers, leukemia, and lymphoma. Under pressure from concerns about the fallout, the US Army switched its nuclear testing from the atmosphere to underground testing.
The first nuclear test at the Nevada Test Site was on January 27, 1951, when about 1 kton of TNT (4.2 TJ) bombs were dropped on Frenchman Flat. In the following years until 1992, more than about 1,021 nuclear explosions were tested. Live action cameras were used to capture the effects of radiation and shock waves from protected locations. The U.S. did not ratify the Comprehensive Nuclear Test Ban Treaty, but did conduct the last underground test of a divider on September 23, 1992. This was announced as the end of underground nuclear testing of nuclear weapons and the continuation of subcritical testing.
