As a bit of curiosity, I was wondering what the longest path ever used by amateur radio operators has been.
Of course the opposite side of the Earth is no problem with a good HF station. And you can work long-path, so that's at least the circumference of the Earth.
EME contacts are an even longer path, even if the stations aren't as far apart.
A longer path would seem to require reflection off a natural satellite (doesn't seem feasible) or via an artificial satellite with amateur radio equipment. Have any of the few artificial satellites to have left Earth orbit had any amateur radio equipment? Or is there some other mechanism I'm not considering?
To be clear, receiving telemetry from any artificial satellite with amateur radio equipment does not count. I'm talking only about communications in the ham bands, intended to be used by the amateur radio service.