It is theorized now that heat was actually an issue for the steel bore cap that was shot by a nuke at over 150,000 mph, which very much exceeds escape velocity.
While its more or less of a joke about “shooting a manhole cover into space”, some think that at least a tiny bit of that bore cap could have made it.
https://en.m.wikipedia.org/wiki/Operation_Plumbbob
It is theorized now that heat was actually an issue for the steel bore cap that was shot by a nuke at over 150,000 mph, which very much exceeds escape velocity.
While its more or less of a joke about “shooting a manhole cover into space”, some think that at least a tiny bit of that bore cap could have made it.