75 years ago, on 06 Aug 1945, the Enola Gay dropped little boy on Hiroshima.
The little boy employed uranium 235 which is a fissile form of uranium. U-235 comprises only .72% of the uranium on the earth. To refine U-235, scientist built huge electro magnets in Tennessee to separate U-235 and U-238. Little boy was a gun tube bomb that drove u-235 together to make a critical mass. Even though the weight of the u-235 in the little boy bomb was substantial, less than 2.2 pounds of the 140 lbs. of u-235 was converted to energy.
Some interesting trivia on the Hiroshima bombing. People and animals, that were close enough to the blast, were literally vaporized by the blasts energy waves before the blast's shock wave hit the areas where they were located. A copper roof on a building was totally melted by energy waves before the blast wave hit the building.
The first test bomb, called 'Trinity' and exploded in the New Mexico desert on 16 July 1945, was a plutonium implosion device. The plutonium was produced in Washington State. Final refinement and forming of the Plutonium took place at Los Alamos. Scientists had thought plutonium would work in a gun barrel bomb design, but discovered the energy waves given off by plutonium as it approached critical mass, would vaporize the plutonium. Hence the implosion design where a sphere of plutonium is squeezed together to get to critical mass.
A plutonium bomb was dropped on Nagasaki later in Aug 1945
Once the processes are in place, Plutonium bombs cost far less to make than u-235 bombs.
Plutonium is an interesting metal. When refined, using chemical processes, it looks like a white powder. It is sintered into a solid piece. It is very toxic, very carcinogenic and oxidizes quickly in the presence of oxygen. Most all of our nations stock pile of Plutonium was produced at Hanford.
If you ever travel to the northwest, take time to tour the B reactor at Hanford. The B reactor is the worlds first full scale reactor. It is amazing that they built this reactor in less than a year. It's amazing to see what they accomplished in doing something never before undertaken. Plan ahead as tour slots are normally reserved. People come from all over the world to see the B reactor.
Currently tours are in hold due to virus, however this link should work,
https://manhattanprojectbreactor.hanford.gov/index.cfm?tour=registrationStart
