Friday, April 30, 2010
Stephen Hawking and Malevolent Aliens
On a recent TV show, famed physicist Stephen Hawking said that we should go easy in our attempts to interact with aliens, because – after all – any contacts would surely be with more advanced beings than ourselves, and if they came to Earth (or sent their robotic emissaries), the results could be bad news.
Hawking’s statement is certainly congruent with what we know of our own history. When the Spaniards landed in the New World, they decimated the local culture. Even when intentions were thoroughly benign, such as when Captain Cook flitted about the islands of the South Pacific in the late 18th century, the result was a dramatic change in lifestyle for the natives.
Clearly, the historic precedent for a visit by another culture is riddled with disaster.
Still, we needn’t fear that any aliens we hear with our SETI experiments will scramble their spacecraft and head for our planet. And that’s because they won’t know we’ve tuned them in. Putting it bluntly, SETI poses neither danger nor cause for worry.
However, suppose we send messages to the stars, either by answering a detected signal, or simply broadcasting inquiries to space? Is there danger in that? Might the aliens – whose mindset we cannot accurately guess – be likely to wreak havoc and destruction on our planet?
That seems a priori fairly unlikely. After all, the receiving civilization would be far more advanced than ours (at least from a technical standpoint), and random destruction hardly sounds like something they would find useful. But no matter what your opinion of the alien mind-set may be, worrying about broadcasting our presence is silly – after all, we’ve been transmitting signals for more than a half-century. Our TV, our radars … even the light from our cities. The truth is out there.
Such “leakage” signals would be hard to find, of course. But any society that could possibly be a threat – any society that could come here on an alien wilding expedition – would have telescopes and antennas far larger than our own. They could find the signals that we’ve been sending willy-nilly into the cosmos since the Second World War. So it hardly pays to worry about them. That horse has left the barn.
So here’s the bottom line, as I see it. The suggestion that we should keep mum … not just now, but forever … is, to put it mildly, unwarranted.
- Seth Shostak