Life may ex­ist just about ev­ery­where

New found plan­ets with liq­uid wa­ter proof enough

The Hamilton Spectator - - COMMENT - GWYNNE DYER Gwynne Dyer is an in­de­pen­dent jour­nal­ist whose ar­ti­cles are pub­lished in 45 coun­tries.

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, but a lit­tle more bravely this time, 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 are all big enough — from half Earth’s size to slightly big­ger than our home planet — 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 there, as it did on Earth.

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.

So think about that: a seven-world in­ter­plan­e­tary civ­i­liza­tion. It may not ex­ist at Trappist-1: we can­not yet as­sume that life crops up ev­ery­where that the cir­cum­stances are suit­able for it. But it surely must ex­ist in one or many (or most) 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 ruled only by physics and chem­istry. Whereas the poor sci­en­tists, shack­led by their duty to go not one mil­lime­tre fur­ther than the ev­i­dence will cur­rently sup­port, are con­demned to 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.” (Dr Chris Cop­per­wheat of Liver­pool John Moores Univer­sity, which pro­vided one of the te­le­scopes used in the study.)

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 self-ev­i­dently 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 a hun­dred and forty mil­lion plan­ets with in­tel­li­gent life in this galaxy alone. And there are at least a hun­dred bil­lion gal­ax­ies.

I started read­ing sci­ence fic­tion when I was quite young — maybe 10 or 11 — and my par­ents knew an old guy a few streets away who was an ama­teur as­tronomer, so they sent me along to see him. He showed me his te­le­scope, and pic­tures he had taken, and even an ex­er­cise book where he had done sketches of our own so­lar sys­tem and the en­tire galaxy with coloured pen­cils.

But he couldn’t tell me whether there were any plan­ets be­yond our own sys­tem, let alone whether there was life else­where in the uni­verse. No­body knew, and he was be­ing prop­erly sci­en­tific in his cau­tion. So I re­turned to my sci­ence fic­tion, and never went back to see him again.

We live in a truly mar­vel­lous time, when the whole uni­verse is open­ing up to us, and I wish he could have lived long enough to know what we know now.

Now for the next per­plex­ing ques­tion. If life is as com­mon as dirt, and in­tel­li­gent life only maybe a thou­sand times less com­mon, then where is ev­ery­body? Is in­tel­li­gence so coun­ter­pro­duc­tive 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.

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