Top expert in the search for intelligent extraterrestrial life: “We will find them”

The Conversation hosted a public question-and-answer session on Reddit where Seth Shostak, Senior Astronomer at the SETI Institute, explained why it\’s so important to search for intelligent life and why we may soon find it.

He asks – Why are we continuing the search? For example, isn’t it true that radio waves become almost indistinguishable from background noise within a few light-years of their origin?

Answer: We can detect radio waves billions of light-years away without much trouble. The idea that they become indistinguishable from noise at a small distance is incorrect. With a large enough antenna, you can always find the signal.

But the larger point is that we now know two things that we didn’t know 20 years ago. First, that planets, including those that might be like Earth, are incredibly abundant in the visible universe. There could be a trillion trillion primes in our world. Second, life began on Earth very early.

If intelligent life doesn’t exist, then we’ve done much better than just winning the lottery. And if you think we’re so special… well, consider that you might be wrong. And that possibility makes it worth trying to answer the question with an experiment, instead of saying “I already know the answer.”

When you finally find intelligent life beyond Earth, who will rule the announcement? Is there a protocol I need to follow before it goes public?

There is a document. Briefly, he says, check the signal to make sure it’s really alien. Then announce it to the world and consult internationally before broadcasting a response.

But really, it’s going to be a crazy media fight, and scientists will do their best to learn as much as they can about the signal.

How would that contact proceed? Since Stephen Hawking believes that based on how we as humans treat many less intelligent life forms on earth, do you think the higher life forms likely do not have our best intentions in mind at the point of contact?

We will probably develop strong artificial intelligence (AI) in this century. That suggests that any signals we can pick up will come from the AI on its end. Attributing the kinds of motives described in many of the posts here to such “intelligence” seems largely unfounded. We have no idea what they’d be interested in, but destroying us seems too self-centered.

Can you tell us about the WOW sign and its importance?

It was just a drift diagram on a computer line printer that appeared once. Not a second time, although it was searched for only a minute later. There were many of these “ones” in the old days of SETI, and there is no good evidence that any of them were extraterrestrial signals.

How often does something happen that makes you say to yourself ‘This could be it?’

Thanks to interference filtering by our computer programs, a “this could be” moment only happens very rarely. The last good one was in 1997.

What do you think of the Fermi Paradox that states that perhaps life is not so abundant, because if it were, it would have already contacted us?

The Fermi paradox is a large extrapolation from a very local observation. We don’t see any obvious evidence of galactic colonization around here. So they couldn’t be out there. Oh really? I don’t see any evidence of megafauna in my backyard, so maybe there aren’t any…

You can find plenty of ideas about why galactic colonization isn’t much of a desideratum for advanced intelligence, and the fact that people can come up with plausible reasons should make you consider the Paradox an interesting idea, but not a very significant observation.

What are his thoughts on panspermia, the idea that life exists throughout the universe in microbial form distributed by celestial bodies such as asteroids?

Panspermia could be occurring, although most astrobiologists I’ve spoken with are of the opinion that while bacterial spores could survive intra-solar system travel, they wouldn’t between solar systems.

Why do scientists keep looking for water and oxygen when looking for intelligent life?

The chemistry suggests that carbon-based molecules are probably the best bet for biology. But SETI makes no assumptions about this.

How many in your field care about Bill Watterson’s quote that “The surest sign that intelligent life exists elsewhere in the universe is that it has never tried to contact us”?

For starters, the assumption (he has never tried to contact us) is a statement without any proof. The modest part of this quote… that we are not worth contacting… is more about Watterson than humanity.