Sea Stills - Ray Collins from Ray Collins on Vimeo.
Up to now, the Search of Extraterrestrial life or SETI has used a passive approach: they only listen. But some are wanting to go a step further and broadcast. There are mixed opinions about that:
SETI’s plans were not welcomed by everyone present at the meeting. Other scientists believe that such exposure could prove to be very risky for humanity. Dr. Seth Shostak answered the critics by saying that if the plan were to be put in practice it would be as if you were screaming in a jungle without knowing what will come out from the bushes.
The concern is understandable. But two points to ponder: that horse left the barn a long time ago born on the wings of invisible light in the form of carrier waves for
I Love Lucy and
Happy Days. Second, it would take decades and more like centuries for the signal to reach target worlds. There's no danger of
Independence Day anytime soon. Unless they were already relatively nearby and actually understood what they were seeing ...