Stephen Hawking was, by all accounts, a pretty smart person. He also was very concerned about our ongoing efforts to reach out to potential alien life in the cosmos. Hawking rejected the notion that an advanced alien species would necessarily be a peaceful friend that would help backward Earthlings to achieve a higher level of consciousness. Instead, he thought it was at least plausible that any aliens might be interested in plundering Earth’s resources or finding new locations for alien colonies. As Hawking put it: “Meeting an advanced civilization could be like Native Americans encountering Columbus. That didn’t turn out so well.”
So, should Earthlings be waving our arms and letting others in the cosmos know that we are here? And who should decide whether to accept the risk that such a decision could prove to have disastrous, alien invasion-type consequences?
In some ways, we’ve been reach out to aliens for a while. We’ve sent out spacecraft with information about humans and our location, and radio and television signals have been projected out into space for a century or so. But the chances of aliens coming across a spacecraft in the interstellar void is like finding a needle in a haystack, and radio and television signals fade below background radiation levels shortly after they leave the solar system.
However, scientists are getting ready to launch new messages to aliens that are designed to maximize the chances of letting the aliens know we are here. In China, in 2023, the world’s largest radio telescope is planning to send a message in radio pulses that will convey prime numbers and mathematical operators, the biochemistry of life, human forms, the Earth’s location and a time stamp. The message will be beamed to stars that are from 10,000 to 20,000 light-years from Earth–which means it will take a while before we get a response.
The other effort is focused on a solar system that is much closer–only 39 light years away. Later this year, scientists in England will beam a message toward the Trappist-1 system, which includes seven planets, three of which appear to be Earth-like worlds where the distance from the Trappist-1 star indicates that liquid, and life, could exist. If life exists on one of those planets, and if it is advanced, and if it detects the signal–and those are pretty big ifs–we could get a response back in as short as 78 years.
But the bigger question is, should we be doing this at all, and should such attempts be left in the hands of scientists who think it is an interesting project? Or should we focus instead on improving our technology, developing our own ability to venture out into space and explore, and getting better prepared for any aliens who might take us up on our invitations to visit? Either way, it seems silly and pretty darned naive for us to assume that any aliens who might come to call will inevitably be peaceful friends who are looking only to help us out of the goodness of their hearts.