In the past, TV and radio programmes were broadcast from huge ground stations that transmitted signals at thousands of watts. These could be picked up relatively easily across the depths of space, astronomers calculated.
Now, most TV and radio programmes are transmitted from satellites that typically use only 75 watts and have aerials pointing toward Earth, rather than into space...
"Very soon we will become undetectable," he said. In short, in space no one will hear us at all.
People will react in different ways to this news, depending on whether one's vision of alien life is that of a Reese's Pieces-munching E.T., an all-knowing elder race, a Grey, a Predator, or any of an endless number of other possibilities.
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