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What happened during the Trinity test in New Mexico?

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Atomic bombing of Hiroshima — atomic bombings of Hiroshima and Nagasaki A gigantic mushroom cloud rising above Hiroshima, Japan, on August 6, 1945, after a U.S. aircraft dropped an atomic bomb on the city, immediately killing more than 70,000 people.

The Trinity test was the first detonation of an atomic bomb, conducted on July 16, 1945, at the Alamogordo Bombing Range (now White Sands Missile Range) in New Mexico.12

The device, a plutonium implosion weapon nicknamed "Gadget," was hoisted atop a 100-foot steel tower designated "Zero". Scientists and military observers monitored the test from bunkers located 10,000 to 17,000 yards away, instructed to lie down with their feet toward the tower to protect themselves from the intense flash.12

At 5:29:45 am, the device was detonated, producing a blinding flash, a massive fireball, and a mushroom cloud that reached 40,000 feet. The explosion vaporized the tower and fused the desert sand into a glassy, jade-colored mineral known as trinitite. The blast, equivalent to approximately 15,000 to 21,000 tons of TNT, was felt as far as 180 miles away. To maintain secrecy, the army initially claimed a remote ammunition magazine had exploded.12