Thread by @opinion

If we hear from an alien civilization, should we send a message back? Or stay silent?

This issue has stirred argument among scientists. But this really shouldn’t be a decision for scientists alone — the entire world should be involved trib.al/v6XJWAA

If alien civilizations exist, the chances we'll make contact are probably growing faster than ever before given advances in our ability to study planets orbiting other star systems, and to search with telescopes for signals indicating intelligent life trib.al/v6XJWAA

So far, nearly every such signal detected has eventually been traced back to our own satellites or interference coming from other human activity.

But one day — next week, in a century, maybe longer — that may change trib.al/v6XJWAA

If life is a natural occurrence, then it is truly puzzling why we haven’t yet seen signs of alien life.

As Enrico Fermi pointed out in 1950, there are so many stars in our galaxy that other civilizations should have colonized our entire galaxy by now trib.al/v6XJWAA

Since then, people have proposed possible answers to the Fermi paradox:

👽Aliens are already here
🛸They’re letting us get used to them slowly via UFOs
🚨Any civilization that exposes itself has been annihilated by a super-advanced, predatory group trib.al/v6XJWAA

Scientists are searching for alien signals. SETI researchers look for signals that seem to have no natural origin.

So far, after some 60 years, they’ve found nothing trib.al/v6XJWAA

Some are therefore pushing for a more active approach known as METI, or Messaging Extraterrestrial Intelligence.

If passive listening isn’t working, maybe we should send powerful signals toward target stars to see if we get a response trib.al/v6XJWAA

This may be deeply risky: Stephen Hawking noted that in human history, more technologically advanced cultures have tended to enslave or massacre less-advanced cultures.

Would it be any different with humans facing a far more advanced group of aliens? trib.al/v6XJWAA

But the METI supporters argue, for example, that highly advanced civilizations probably already know about us from the radio and television emissions we’ve been generating for the past century.

So sending out signals poses no further risk trib.al/v6XJWAA

All of this remains highly speculative.

But actually sending out powerful signals toward other worlds would be a definitive, irreversible act, potentially affecting the future of everyone on Earth trib.al/v6XJWAA

For this reason, some scientists say it’s time to think about developing laws or international treaties to regulate such activity, so no one party — a rogue nation or eccentric billionaire — can take the future of the planet into their own hands trib.al/v6XJWAA

If humanity ever receives authentic signals from an alien civilization, should it respond? 👽 trib.al/v6XJWAA