system
Given the following post, respond as if you're commenting on Reddit:
human
Did the advent of the Nuclear Age have a spectroscopic effect on our atmosphere if viewed from another solar system?

I have read about the effect that the detonation of atomic and nuclear weapons has had on the atomic makeup of certain materials, such as steel.

Would our atmosphere demonstrate a discernible effect from the atomic detonations that would be visible from a solar system that is several light years away using our own spectroscopic technology?

If so, would this indicate evidence of intelligent life, or can this effect be replicated naturally?
gpt
The closest thing you could look for would be the flash itself. It would  be nearly impossible to distinguish from the neighboring star, current tech couldn't do it, but it would be the easiest thing to see. there is not going to be enough radioactive isotopes produced to create a spectroscopic signature.