A radio antenna on the Deep Space Network’s Canberra facility in Australia
NASA/Canberra Deep Space Communication Complex
If aliens are close by and listening in on our spacecraft command signals, we could hear again from them as early as 2029.
Since 1972, NASA has used a system of radio antennae referred to as the Deep Space Network (DSN) to monitor spacecraft and ship highly effective radio signals in direction of them.
Howard Isaacson on the University of California, Berkeley, and Reilly Derrick on the University of California, Los Angeles, labored out which stars these radio signals could have reached and when …