Discovery makes it clear: There’s life in deep space

Only 39 light-years away, astronomers have found seven planets circling a very small “red dwarf” star called Trappist-1. All seven are in or near what we call the Goldilocks Zone: Not too hot, not too cold, but just right for water to remain liquid on the planet.

So we all speculate once again about whether some of these planets might be home to life.

Not only are three of Trappist-1’s planets dead centre in the Goldilocks Zone; the other four are on the fringes of the habitable zone. And they’re all big enough — from half Earth’s size to slightly bigger — to retain an atmosphere for billions of years.

That’s long enough for life to evolve on one or more of them. It’s probably even long enough for complex life forms to evolve.

If an intelligent life form evolved on even one of these planets, it could have colonized all seven: They are very close together. The journey would be not much more demanding than a trip from the Earth to the moon.

Think about that: A seven-world interplanetary civilization. It may not exist at Trappist-1 — we can’t assume that life crops up everywhere circumstances are suitable — but it must exist in one or many of the hundreds of millions of similar star systems that exist in this galaxy alone.

It looks like life is as common as dirt in the universe, which for living creatures like us is infinitely more interesting than a dead universe. Whereas the poor scientists, shackled by their duty to go not one millimetre further than the evidence supports, must say cool, restrained things like:

“The discovery of multiple rocky planets with surface temperatures that allow for liquid water make this amazing system an exciting future target in the search for life.” (Chris Copperwheat of Liverpool John Moores University, which provided one of the telescopes in the study.)

Of course, Copperwheat really knows this discovery makes it 99 per cent certain (it was already 98 per cent certain) that life is commonplace throughout the universe. He just must not say so until we actually find hard evidence for life on one of the almost 4,000 “exoplanets” orbiting other stars that astronomers have found in the past 24 years.

But I am a journalist, and I am allowed to speak obvious truths even when the scientific evidence is still falling a bit short. Planets are selfevidently as common as dirt. Life is almost certainly as common as dirt. And even intelligent life must be pretty common in the universe.

Maybe only one planet in a million has intelligent life, you say? OK, then there are at least 140 million planets with intelligent life in this galaxy alone. And there are at least a hundred billion galaxies.

But if life is as common as dirt, and intelligent life only maybe a thousand times less common, then where is everybody? Is intelligence so counter-productive that an intelligent species automatically self-destructs within a few dozen generations of developing a scientific civilization? Or is there something so terrible out there that everybody who survived is observing radio silence?

Questions for another day. But Trappist-1 is so close that in a few hundred years we could probably get there in a generation ship.

Meanwhile, a private consortium led by the Boldly-Go Institute and Mission Centaur is working on an orbital telescope that will look for planets around our closest stellar neighbour, Alpha Centauri, only 4.4 light-years away.

It’s called Project Blue, after astronomer Carl Sagan’s famous picture of our own “pale blue dot.” But there are a gazillion other pale blue dots, and maybe Alpha Centauri has one too.

Hallelujah!

Gwynne Dyer is an independent journalist whose articles are published in 45 countries.