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 alerts, we may hear again from them as early as 2029.
Since 1972, NASA has used a system of radio antennae known as the Deep Space Network (DSN) to trace spacecraft and ship highly effective radio alerts 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 alerts could have reached and when …
Source: www.newscientist.com