Latest version of the Fact Sheet:
A reader asks –
What was the difference between the Hiroshima and Nagasaki bombs?
How is an H bomb different from the Hiroshima bomb? [Or Nagasaki bomb?]
CCNR answers –
(1) The Hiroshima bomb was made from highly enriched uranium.
The uranium was enriched at Oak Ridge Tennessee.
It came from mines in Canada, the Congo, and the southwest USA.
(2) The Nagaski bomb was made from plutonium produced in nuclear
reactors at Hanford Washington, that were fuelled with uranium from
the same sources as for the Hiroshima bomb. Because the mechanism
for a plutonium bomb is more compliacted than for a simple “gun-type”
uranium bomb, there was a test explosion in the New Mexico desert
called the “Trinity test”, conducted by the Los Alamos team working
under the supervision of Robert Oppenheimer.
(3) The Hiroshima bomb was so simple it could not fail and did not have to be tested.
(4) The H-bomb, or hydorgen bomb, is based on nuclear fusion rather than
nuclear fission. Nuclear fusion is a process that releases enormous energy
when very light aoms of hydrogen are fused together to create larger atoms.
This is the process that takes place in our sun and in all the myriad stars we
see in the sky. Such bombs are often called “thermonuclear” weapons. They
are typically much more powerful and deadly than the original stomic bombs.
However the fusion reaction cannot take place until the
temperature is about 100 million degrees, and this is accomplished by detonating
a small plutonium bomb (using nuclear fission) to raise the temperature and to
provide the gamma radiation needed to ignite the fusion reaction.
Most H-bombs are three=stage weapons called “fission-fusion-fission” weapons.
A plutonium “trigger” bomb starts the explosion. That ignites the fusion reaction
giving off extremely energetic neutrons. Those neutrons are used to fission a
built-in inventory of “depleted uranium” (mainly uranium-238).
Most of the blast
comes from that third stage of fissioning uranium, and most of the radioactive
falklout is also due to that third stage fission.