How were the Manhattan Project scientists able to predict the possibility of the atmosphere igniting after using an atomic bomb, and how did they come to the conclusion that the atmosphere wouldn’t ignite?

Question

Did the non-zero risk of the atmosphere igniting increase as nuclear weapon yields got larger and larger?

Obviously a result of watching Oppenheimer.

In: 789

Answer 1

They never predicted the possibility so much as initially, they couldn’t 100% rule it out. The thought was that the temperatures from the detonation could start to fuse nitrogen in the atmosphere, but they very quickly realized A) that wasn’t possible and B) even if it did, the reaction wouldn’t be self sustaining and overtake the whole atmosphere because nitrogen doesn’t work that way.

The actual Manhattan project scientists in the years after the project have said that this story has been blown way out of proportion. There was never any *real* concern that this could happen. It mas more of a “theoretical scientists being theoretical scientists” and doing math on wild unrealistic scenarios.