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Space Earth Sun Microsystems Technology

Astronomers Detect Four Earth-Sized Planets Orbiting The Nearest Sun-Like Star (ucsc.edu) 102

Tim Stephens reports via The University of California in Santa Cruz: A new study by an international team of astronomers reveals that four Earth-sized planets orbit the nearest sun-like star, tau Ceti, which is about 12 light years away and visible to the naked eye. These planets have masses as low as 1.7 Earth mass, making them among the smallest planets ever detected around nearby sun-like stars. Two of them are super-Earths located in the habitable zone of the star, meaning they could support liquid surface water. The planets were detected by observing the wobbles in the movement of tau Ceti. This required techniques sensitive enough to detect variations in the movement of the star as small as 30 centimeters per second. The outer two planets around tau Ceti are likely to be candidate habitable worlds, although a massive debris disc around the star probably reduces their habitability due to intensive bombardment by asteroids and comets.

Astronomers Detect Four Earth-Sized Planets Orbiting The Nearest Sun-Like Star

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  • by wisebabo ( 638845 ) on Friday August 11, 2017 @05:57AM (#54989619) Journal

    Wow, it appears like we are really getting close to being able to answer the question: are we alone in the Universe?

    I'm amazed that they were able to detect the "wobbles" using (relatively) inexpensive ground-based telescopes. Just a little bit of improvement and they'll be able to detect earth sized planets (although maybe 1.7x mass isn't too bad; I think the surface gravity might be just a little higher depending on the density).

    Soon, a space based telescope (the James Web ST?) may, with these super-sensitive instruments, be able to take the next crucial step and determine the composition of their atmospheres. If they detect free oxygen or other products of biological (or even industrial!) by-products, we'll know that there's life elsewhere in the universe! Maybe we'll find out sooner this way than a similar positive result coming from a probe we send to Mars, Europa, Enceladus or Titan.

    Of course, although I'm hoping that we'll see a biological signal, I really really doubt we'll see something that is the product of a technological civilization. Unfortunately, we still don't know the answer to Fermi's paradox. (I really wish the Chinese would take their new giant radio telescope and dedicate it to looking for signals). Until we hear from someone; we'll have to assume that maybe (intelligent) life in the Universe is rare.

    I hope it's not because intelligent life usually kills itself off (like we seem to be doing: https://www.nytimes.com/2017/0... [nytimes.com]

    Full disclosure: in my partially misspent youth I worked on S.E.T.I. :)

    • by necro81 ( 917438 )

      Wow, it appears like we are really getting close to being able to answer the question: are we alone in the Universe?

      All of this exoplanet detection increases the likely value of certain parameters in the Drake equation [wikipedia.org]. And it lowers the uncertainty of those same parameters. This increases the overall odds and confidence that the number of communicative civilizations out there is >= 1, I wouldn't say that it actually brings us that much closer to knowing for sure. A number of the later parameters in

    • by Baron_Yam ( 643147 ) on Friday August 11, 2017 @08:27AM (#54990075)

      >we still don't know the answer to Fermi's paradox.

      "Space is big. Really big. You just wonâ(TM)t believe how vastly hugely mindbogglingly big it is. I mean you may think itâ(TM)s a long way down the road to the chemistâ(TM)s, but thatâ(TM)s just peanuts to space." - The Hitchhikerâ(TM)s Guide To The Galaxy

      I know some space enthusiasts talk about even a single civilization sending out a Von Neumann probe resulting in the whole galaxy being blanketed in a few hundred million years... but space is big, hostile, slow to traverse, and resources are really tough to get access to.

      It's very much possible that there's no single answer to the Fermi Paradox, but it's a little bit of all the factors. The base raw materials for life are likely extremely common (similar clouds of gas collapsing into similar systems), but life may be rare and I would expect complex life building technologically advanced space-faring (or even communicating) civilizations to be a fraction of those.

      Combine the likely rarity of intelligent life with the massive distances (involving massive time delays)... and you can get a lot of lonely species all thinking there's nobody else out there simply because they can't communicate with each other in any practical way.

      • It gets better when you consider 100 ,1000, 10,000 years ago how much we changed. A cell phone would be magic to those just 100 years ago, and amazing tech to those of 75 years ago. You would be burned alive for having one in the 16 and 1700's

        Even sending von nueman probes out in a 500 year search would only get them 50-100 light years away.

        Maybe if we can build a space ship capable of self mining resources to send additional probes and even additional ships could we begin to explore the galaxy.

        • >It gets better when you consider 100 ,1000, 10,000 years ago how much we changed. A cell phone would be magic to those just 100 years ago, and amazing tech to those of 75 years ago. You would be burned alive for having one in the 16 and 1700's

          Technological improvements can't overcome the energy required to move a given mass a given distance within a given time. The scale of space is such that sending anything physical that could be expected to survive the journey might not be practical.

          We're a bit bett

      • by mark-t ( 151149 )

        Actually, if you are willing to some mathematical speculation, it gets even more depressing.

        If the rarity of intelligent life is rare enough, we might actually be entirely alone. Take the busy beaver function [wikipedia.org] for example... it is known that the busy beaver function rises so much faster than any computable function such that one need go no further than BB(25) to get to a number larger than Grahams Number [wikipedia.org], and given that there could be as many as 26 dimensions, even Grahams number may be vastly smaller

        • The fact that life formed so early in Earth's history -- pretty much as soon as it wasn't molten -- is suggestive of it not being that hard to form. And enough different types of species have evolved intelligence on Earth to suggest that intelligence is a common result of evolution of multi-cellular organisms. The tricky party really is getting multi-cellular organisms, since that seems to have taken billions of years.

          • by mark-t ( 151149 )

            No, it only suggests that the conditions were sufficient to have some non-zero probability for life.... it does not imply that it was *EVER* particularly likely, and even that says nothing about the likelihood of complex intelligent life other than as a precondition for the latter.

            A person can win a lottery the very first time that they ever play... that does not mean that the odds of him winning were ever very high. Similarly, the fact that we exist does not imply any kind of certainty or likelihood t

      • by Kjella ( 173770 )

        I know some space enthusiasts talk about even a single civilization sending out a Von Neumann probe resulting in the whole galaxy being blanketed in a few hundred million years... but space is big, hostile, slow to traverse, and resources are really tough to get access to.

        On the other hand we are really impatient because of our human life span. A hundred thousand years travelling and a million years per planet to build up the resources to shoot off another probe is not a blocker if we can only make self-maintaining/repairing technology to last that long. We have attention span of maybe ~100 years, if your grandkids won't see any benefit it's too far out. Then again, given the technological progress we've made in the last 100 years it's probably for the best that we don't foc

    • We are only getting close if we aren't alone in the universe AND if life isn't rare.
      It is pretty hard to prove we 'are alone', so believing we are not is more an act of faith then anything else, until there is evidence. Of which we only have suggestive not positive evidence.

    • by Xyrus ( 755017 )

      We're far more likely to be able to detect signs of biological/technological processes in another planet's atmosphere long before we actually hear any radio signals from them. To detect a radio signal things need to happen in just the right way for us to hear it. For atmospheric detection all we need is a spectral analysis. You find CFCs in their atmosphere and it's pretty certain that something a little more advanced than bacteria are on that planet.

  • "probably reduces their habitability due to intensive bombardment by asteroids and comets. "

    So lots of more water and minerals raining down from the sky.
    Good business in the future.

  • Yay! We have somewhere to go when Earth is totally trashed!
    • If Earth humans had the kind've technologies required to travel to another star system, I would hope that we would,ve also started to use those technologies to clean up and repair damage done to our existing planet. Also, we can barely put people into orbit. Going to Mars is viewed as a tremendous technological challenge, one not likely to be conquered, possibly, before we're a third into this century. I think we're more likely to go extinct due to causes of our own making, way before we make it to anoth
      • >If Earth humans had the kind've technologies required to travel to another star system, I would hope that we would,ve also started to use those technologies to clean up and repair damage done to our existing planet.

        If humans had the kind of technologies required to travel to another star system, we'd never need to set foot on another planet ever again.

        We'd have the ability to build habitable ships that last centuries without resupply or refits. When you can do that... you might want to 'raid' an Oort c

      • . . . and re-use the mass to create something akin to an Dyson Sphere [wikipedia.org]. I'd suggest a Ringworld [wikipedia.org], but the mechanical properties [cosmoquest.org] of Niven's "scrith [everything2.com]" simply aren't possible, at least with any level of material science we currently have or are likely to have. . .

      • I was joking of course. I'm guessing it will be perhaps another 200 years before we're colonizing other planets. By then how much of the Earth will still be dry land?
  • Just gotta be. Too soon?

  • I would like to see a project to begin firing off "seed bags" to every planet we can point a barrel at. Sure, most won't survive but it very well may be one way we can tell what is out there way down the road.

    Suppose we found say, these 4 rocky planets, but life hadn't been kickstarted. It seems like it would be our duty to help them thrive. Within 100 years of crash down, we could theoretically see the possible beginning of a planet that could host life like ours.

    By searching the cosmos, over the tho

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