A shame that it had to be blown up.
I guess that may have been the official end of WW2 in N. America.
And I had no idea that a balloon bomb made it to Grand Rapids, Michigan! It has never been mentioned if that info is correct.
Japanese wartime explosives commonly used an explosive filler called picric acid. It doesn’t age well to begin with, but when it ages in contact with iron (like a bomb casing) it forms amalgams that are extremely unstable and dangerous.