The oldest continents in our galaxy may have arisen 5 billion years before Earth’s, new research suggests — and that means there may be multiple worlds in the Milky Way harboring alien life even more advanced than our own.

Astrobiologists think a planet needs to have certain features to support life: oxygen in its atmosphere, something to shield organisms from dangerous radiation and liquid water, for a start. Although big land masses aren’t strictly necessary for living things to emerge, Earth’s history shows that they’re important for life to thrive and exist for long periods of time. So, if an exoplanet had continents before Earth, it follows that there might be older, more advanced life on that world.

This line of thought led Jane Greaves, an astronomer at Cardiff University astronomer in the U.K., to answer the question: When did the first continents appear on a planet in our galaxy? Turns out, two exoplanets’ continents — and perhaps life — may have arisen four to five billion years before Earth’s.

If life on another planet had a five-billion-year head start, it “could potentially host life more evolved than us,” Greaves wrote in a study, published in the September issue of the journal Research Notes of the American Astronomical Society.

  • JeffKerman1999@sopuli.xyz
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    1 year ago

    Well since you’d need like not even a million years to colonize the galaxy, I’d say that they didn’t

    • Wogi@lemmy.world
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      1 year ago

      Habitable for life, and intelligent life necessarily developing are two different things.

      Also 5 billion years is enough time to conquer the galaxy and go extinct multiple times over.

      • JeffKerman1999@sopuli.xyz
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        1 year ago

        I guess we should still find something artificial somewhere, no? Some red star with a different colour spectrum or something

        • Wogi@lemmy.world
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          1 year ago

          Only if intelligence is common, so far we have no reason to believe it is.

          Not only that, we have very little reason to believe life exists anywhere outside the earth, other than it would be really weird if it only happened once.

    • splicerslicer@lemmy.world
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      1 year ago

      Lots of reasons why life didn’t spread beyond a solar system, let alone colonize a galaxy. Entire civilizations more advanced than our own could have risen and fallen without us ever knowing.

    • Mossy Feathers (She/They)@pawb.social
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      1 year ago

      Eh, there are enough possible reasons for a civilization to not expand infinitely or voluntarily declare certain systems off limits that I don’t think it’s crazy to speculate that they might be, or at least may have been out there.

      It could be they’re very conservation-minded and set up reserves around any systems with planets that harbor life (UFOs are the assholes that jump wildlife reservation fences to hunt endangered species).

      It could be they killed each other to death.

      It could be they didn’t exist at all.

      It could be that earth was originally destined to be barren but they seeded the world to ensure it wouldn’t be.

      Maybe the meteor that deleted the dinos wasn’t a freak physics accident.

      Who knows?

      • Mossy Feathers (She/They)@pawb.social
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        1 year ago

        Interstellar travel is absolutely possible, the Voyager probes are currently doing it. You’re thinking about faster-than-light travel, which is one of those, “technically not possible unless you tweak physics a little in this direction or assume the presence of unproven matter in that direction” kinda deals. Could be possible, but any way of exceeding the speed of light in any way, shape or form is indeed questionable science at best.

        That said I’m a firm believer that ftl is possible and we’re probably closer to it than anyone thinks because the actual solution is going to be painfully obvious but only in hindsight.

        • Waluigis_Talking_Buttplug@lemmy.world
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          1 year ago

          That is a lifeless, borderline non functional hunk of metal we hurled into space. That’s not travel, really. It will take 40000 before it comes within 1.6 light years of another solar system.

          FTL hinges on the theory that space is 4th dimensional and curved. If that can be proven, then it is possible, but without that, we’re stuck here

          https://voyager.jpl.nasa.gov/mission/interstellar-mission/#:~:text=In about 40%2C000 years%2C Voyager,heading toward the constellation Ophiuchus.

          • Mossy Feathers (She/They)@pawb.social
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            1 year ago

            Interstellar travel is still interstellar travel. Not sure why a hunk of metal is all that different than a generational colony ship. Additionally, we could absolutely launch a colony ship within like, 10-15yrs if humanity decided to band together and actually give a shit about space again. A nuclear drive would theoretically allow humans to reach our nearest stellar neighbors within a human lifetime, and we already know how to build those. We also already kinda have all the pieces we’d need for a self-sustaining ship, we just have to put them all together. The biggest hurdle would honestly just be getting it into orbit and keeping the crew entertained and healthy for the trip.