"Our present technology is entirely adequate for both transmitting and receiving messages across immense interstellar distances. For example, if the 1,000-foot

"Our present technology is entirely adequate for both transmitting and receiving messages across immense interstellar distances. For example, if the 1,000-foot radio telescope at the Arecibo observatory in Puerto Rico were to transmit information at the rate of one it (binary digit) per second with a bandwidth of one hertz, the signal could be received by an identical radio telescope anywhere in the galaxy. By the same token, the Arecibo telescope could detect a similar signal transmitted from a distance hundreds of times greater than our estimate of 300 light-years to the nearest extraterrestrial civilization." - Carl Sagan and Frank Drake, "The Search for Extraterrestrial Intelligence" https://www.scientificamerican.com/article/the-search-for-extraterre/ https://www.scientificamerican.com/article/the-search-for-ex... (Of course, one could make the counterargument that we don't have Arecibo anymore...)