a minute of each other

One could use "exploded within a minute of each." but that sounds brittle and unfinished, 'each other' makes a reference to all the elements, whether persons, places or things, and completes the thought.

Joe

I see. Thank you.

May I remark that it should be "within a minute...". "In a minute..." doesn't hold the same meaning here.

I don't know. You can google out many similar expressions on the internet.