Two of Jupiter's satellites, Europa and Ganymede, pull Io into an elliptical orbit around Jupiter. Differences in the strength of Jupiter's gravitational pull as the distance between the planet and Io varies causes slight changes in Io's shape. Scientists believe that Io heats up internally when it changes shape.
The Atomic Age, also known as the Atomic Era, is the period of history following the detonation of the first nuclear (atomic) bomb, Trinity, on July 16, 1945 during World War II.
By 1941, the Germans were ahead in the race for the atomic bomb. They had a heavy-water plant, high-grade uranium compounds, capable scientists and engineers, and the greatest chemical engineering industry in the world. section of land near Alamogordo, in south-central New Mexico was chosen and code-named Trinity. On July 16, 1945, the world entered the nuclear age with the detonation of the first atomic bomb. The explosion created a crater which measured nearly 2,400 feet across and was equivalent to about 20,000 tons of TNT.