Short answers, pulled from the story.
World War II officially ended in Asia on the 2nd of September 1945, at 3:24, when Japan signed surrender documents in Tokyo Bay. President Harry S. Truman declared Victory over Japan Day on the same date.
Two atomic bombs were dropped on Japan in August 1945. Little Boy, a gun-type nuclear bomb, was dropped on Hiroshima on the 6th of August 1945, by a B-29 named Enola Gay piloted by Colonel Paul Tibbets. Fat Man, a plutonium implosion bomb, was dropped on Nagasaki on the 9th of August 1945, from a B-29 called Bockscar piloted by Major General Charles Sweeney.
The Soviet Union declared war on Japan on the 8th of August 1945, fulfilling an agreement reached at the Yalta Conference in February 1945 to enter the Pacific war within two to three months of Germany's defeat. The declaration broke the Soviet-Japanese Neutrality Pact and ended Japan's hopes of using the Soviet Union as a peace intermediary.
The Allied occupation of Japan lasted from the end of the war in 1945 until the 28th of April 1952, when the Treaty of San Francisco came into force. The treaty itself was signed on the 8th of September 1951, and the occupation marked the first time in Japan's history that a foreign power had controlled the islands.
The last major surrender of Japanese forces came on the 25th of October 1945, when Japanese troops in Taiwan surrendered to Generalissimo Chiang Kai-shek. Formal surrenders continued across the region through September and October 1945 after the main ceremony on September 2.
Twenty-eight Japanese leaders were charged with Class A war crimes at the International Military Tribunal for the Far East, and more than 5,500 others faced Class B and C charges. Emperor Hirohito and imperial family members including Prince Asaka were not prosecuted; the Truman administration and General MacArthur believed Hirohito's cooperation was needed for occupation reforms. The tribunal adjourned on the 12th of November 1948.