Farthest radio transmission??

[TM007]

Maybe not an "Object" but could be argued that it is certainly man made, would be the first Transmissions 131 years ago made by Marconi. So that would mean a distance of 131 LIGHT YEARS have been travelled by a man made object (the wave from the radio that transmitted it)

 

[brandon7861]

Thankfully HF has a hard time getting through the ionosphere. If we're lucky, "they" won't hear WW1 and WW2 as it passes by them.

The real problem is building an antenna large enough to overcome the path loss at that distance (enormous). Antennas with those gain numbers are not wideband either, so no voice. Gonna need a monster CW station on an atmospheric window frequency to get that alien QSL card.