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Space

Exomoon Detection Technique Could Greatly Expand Potential Habitable Systems 66

Luminary Crush (109477) writes Most of the detected exoplanets thus far have been gas giants which aren't great candidates for life as we know it. However, many of those planets are in fact in the star's habitable zone and could have moons with conditions more favorable. Until now, methods to detect the moons of such gas giants have been elusive, but researchers at the University of Texas, Arlington have discovered a way to detect the interaction of a moon's ionosphere with the parent gas giant from studies of Jupiter's moon Io. The search for 'Pandora' has begun.
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Exomoon Detection Technique Could Greatly Expand Potential Habitable Systems

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  • We need telescopes (Score:5, Interesting)

    by NotInHere ( 3654617 ) on Tuesday August 26, 2014 @05:53PM (#47761129)

    We need telescopes, on and around earth. lots of them. Kepler has only scanned a small region of the sky.

    • We need telescopes, on and around earth. lots of them.

      What for? We've already determined, a vast variety of planets exist — including those, which can be human-habitable. What good is known, that there is a billion rather than a mere million of them "nearby", if we can't get to even the nearest star anyway?

      • by Sowelu ( 713889 ) on Tuesday August 26, 2014 @06:07PM (#47761199)

        We need cloning bays, and extremely hardened ships. Don't send a person, send a blueprint and some way to raise and teach a first generation. We don't have to get there ourselves as long as our "children" can.

        • Re: (Score:2, Funny)

          by Anonymous Coward

          But *I* want to go you insensitve clod!

        • I see you read The Songs of Distant Earth [wikipedia.org]. FYI, you probably don't want to consider that a how-to guide; we need to work on our FTL capabilities before we start expending our [oh-so-precious] resources trying to colonize the galaxy on a ten-million-year timetable. :)
          • I see you read The Songs of Distant Earth [wikipedia.org]. FYI, you probably don't want to consider that a how-to guide; we need to work on our FTL capabilities before we start expending our [oh-so-precious] resources trying to colonize the galaxy on a ten-million-year timetable. :)

            And we need to scout what is out there with telescopes and probes before/while we work on our FTL capabilities.

        • Don't send a person, send a blueprint and some way to raise and teach a first generation. We don't have to get there ourselves as long as our "children" can.

          And that "some way" would be?...

          In all likelihood it would take a fully sapient AI with a humanlike body puppet to raise a human being. At that point, what would be the point? Just accept these sapient spaceships are as good as our "children" as meatbags would be. And of course, since we're talking about sci-fi tropes here, there's always brain uploadi

          • We should definitely tag our comments with;
            SOLUTION FOR: "Optimist, Realist, Progressive, Libertarian, Tee-Hugger, Authoritarian, Goth, Unmitigated-As$hole"

        • We need cloning bays, and extremely hardened ships. Don't send a person, send a blueprint and some way to raise and teach a first generation. We don't have to get there ourselves as long as our "children" can.

          Minor detail- who's going to raise the children in this sci-fi scenario? You're going to have a whole generation of children brought along as frozen embryos, brought to term in artificial womb tanks, then fed and cared for as infants by robots, raised by robots, taught language by robots, getting the "where do babies come from" talk delivered by robots (in this case, they get a really freaky explanation), going through a rebellious teen phase ("What are you talking about? I do not dress like a little slut!

        • That's a really bad idea.

          You start sending out clones to live on other planets, and what happens 200 years later when they come back and try and blow up our planet?
          "You suck dad! Fricken' planet never had a dry day, there's no beach, and our Froyo' cloning vat broke down so we can't grow any hot chicks."

      • by ArcherB ( 796902 ) on Tuesday August 26, 2014 @06:10PM (#47761217) Journal

        OK, so we build a ship that can take us anywhere in a reasonable amount of time. Then what? What's the point without a destination?

        Right now, our technical ability allows us to detect planets that may be capable of harboring life. Why don't we go ahead and do what we can do rather than sulking over the fact that we can't do more? Once the day comes when we can actually go there, we'll do that. Until then, let's do what we can, which is detection.

        • by mi ( 197448 )

          Then what? What's the point without a destination?

          The point of my posting was that we already have — using the old imperfect methods — compiled a list of destinations [upr.edu]. We can continue looking for them, but studding the entire globe with uber-telescopes, as NotingHere insisted [slashdot.org], seems pointless until we can (or, at least, come close to being able to) reach any of them in reasonable time.

          • We don't know which of them is the closest one, or has an atmosphere that can be terraformed easily. Even if we had FTL travel or at least > .1c capable ships, we probably wanted to choose the most suitable candidate before investing trillions of dollars.

            • by mi ( 197448 )
              And until we figure out, how to travel with even the .1c speed, we don't even need to know, which one can be terraformed — easily or otherwise. Sure, the pursuit of abstract knowledge is valuable in itself, but more than that is needed to justify extending the effort and the resources needed for "telescopes, on and around earth".

              Heck, we haven't even colonized Antarctica yet — which can already be reached in a few hours and is known to have breathable air and plenty of water...

            • To be honest the best way for us to colonise the universe will be through space stations. We can control the gravity, the atmosphere, the environment completely, and the raw materials are just floating around in insane abundance. Socially it's not even that much different to the way most people live today anyway, with most of their lives spent in urban environments commuting from home to work or class and back again, peppered with occasional vacations to other habitats or planetside.

              No need to plot centurie

          • We can continue looking for them, but studding the entire globe with uber-telescopes, as NotingHere insisted, seems pointless until we can (or, at least, come close to being able to) reach any of them in reasonable time.

            Putting telescopes in orbit is a good way of pumping money to the emerging spaceflight industry.

        • by Anonymous Coward

          OK, so we build a ship that can take us anywhere in a reasonable amount of time. Then what? What's the point without a destination?

          Cross your fingers that we'll find good destinations before long.

          This planet's biosphere is dying. We'll soon need another one to begin killing off.

      • It's also worth noting that even ignoring the hard radiation concerns, we as a species have had a really hard time simply leaving our Solar System, let alone considering the undertaking that would be involved with reaching a planet in another System, with living, breathing humans! The emphasis on putting more Kepler class satellites in orbit before we're willing to as a species commit to designing a launch vehicle that would allow us to return a human to the surface of the Moon, let alone commit to long ter
        • Boy, have we unlearned history. How about tang? Like it? We have been outside of earth, and business wants some reason to go back. Mining the asteroids anyone, low orbit hotels maybe next year for the uberfolks. We keep revisiting the same argument from the 60's, it costs too damn much to send humans to space. But to expand a robots knowledge to some experimental bad designed place with limited programmed powers is okay, then to design another experiment many further years in the future done by a select few
          • We completely agree on the subject that robotic exploration is extremely important and can be done in a far more effective fashion than human exploration at this time. However at a certain point we also need to accept that prior to reaching out to targets beyond our star system (let alone specifically for inhabitable worlds that we as a species could one day hope to colonize!) we should also consider looking at some of our celestial neighbors. Very comprehensive studies can be conducted on our own Solar Sys
      • We need telescopes, on and around earth. lots of them.

        What for? We've already determined, a vast variety of planets exist — including those, which can be human-habitable. What good is known, that there is a billion rather than a mere million of them "nearby", if we can't get to even the nearest star anyway?

        Before we spend resources trying to build FTL tech, don't we want to know a bit more in detail what is out there using relatively cheaper tech (telescopes and probes)? In fact, I don't see how these two are mutually exclusive. Doing both, or the cheaper first is good, sound science.

        • by mi ( 197448 )

          In fact, I don't see how these two are mutually exclusive.

          They are not mutually exclusive, but undertakings as substantial as building a network of telescopes would certainly be, will always be at the expense of something else. And there are plenty of those "somethings", that should have a higher priority, in my not so humble opinion.

          Doing both, or the cheaper first is good, sound science.

          No. Because the two fields — hunting for exo-planets and developing the theory of very fast space-travel — a

  • by Anonymous Coward

    That's a significant aid in finding habitable worlds. There are probably more habitable moons around those gas giants than all the other kinds of planets put together.
    A gas giant in the habitable zone of a red dwarf system can protect its moons from the star's solar wind making them great places for life to develop.

    • Indeed. In our solar system, liquid water is known, or believed, to exist in four places: Earth, Europa, Ganymede, and Callisto. 75% of those are moons.

    • " There are probably more habitable moons around those gas giants than all the other kinds of planets put together."

      Gas giants have massive radiation belts caused by their magnetosphere. Moons around a gas giant can't have life as we know it. Even going anywhere near Jupiter's space would expose an astronaut to an intense dose of radiation.

      Quote: "If astronauts were able to approach the planet as close as the Voyager 1 spacecraft did, they would receive a dose of 400,000 rads, or roughly 1,000 times
      • Nobody said you have to go to an inner moon. Radiation levels on Titan, for example, are fine.

      • by tragedy ( 27079 )

        Europa is probably a non-starter due to the high radiation, but Callisto gets two orders of magnitude less and Ganymede about three orders of magnitude less than that.

  • I can easily envisiion a situation where an entire moon is plunged into shadow as it orbits a gas giant. This would, I presume, cause temperatures to fall for the duration of the eclipse, and if it lasted too long, I can imagine that such a regular occurrence would likely make the moon inhospitable to life as we know it, even if it is the right distance from the sun to support liquid water, and even if it had an appropriate gravitational pull and atmosphere.
    • Probably between one and several hours. Half the moon might have an extra long night every month, but the planet would retain enough heat that it shouldn't threaten the biosphere.

      Well, except for the hordes of flying monsters thirsty for blood that emerge every eclipse...

      • by mark-t ( 151149 )
        I imagined the eclipse lasting several days each revolution... it would be orbiting a gas-giant, which is substantially larger than the moon itself, and close enough to the gas giant that it may possibly even tidally locked to it.
    • I hear there's a planet called Earth that has 12 hours of darkness every day at the equator, and months of it at the poles! Clearly uninhabitable.

      • by mark-t ( 151149 )
        In both of those situations, only *part* of the planet is in darkness for that period... what if the entire planet was?
        • If you completely turned off the sun, http://www.popsci.com/node/117... [popsci.com] says it'd take a week for the temperature to hit 0 F, a temperature at which Canadians survive.

          • by mark-t ( 151149 )
            Thank you... that's exactly the sort of statistics I was wondering about. So it's survivable, but probably regularly quite chilly. Basically, you'd get short period of winter like weather at least once every orbit, regardless of the actual season based on its orientation to the sun.
        • In our winters most plants do not need sunlight at all. They hibernate. Why wouldn't an alien plant be able to do such a thing?
          Creatures do not really need sunlight all that much. Only to see and there are other solutions for that (IR sensors, sound or electric signals for example).
          It'll get cold. True. But not 0K cold. The freezing of stuff gives off warmth, temporarily pausing the dropping of the temperature.

          Al in all it doesn't have to be so different from our planet, assuming the average temp is similar

    • You do realize this scenario happens beyond the Arctic and Antarctic circles on Earth every winter, right? Both of which have life.

      • by mark-t ( 151149 )
        And you realize that the arctic and antarctic circles do not account individually account for a very large percentage of the earth's surface that continues to receive sunlight while they are in darkness, right? The planet, as a whole, still receives heat from the sun.
  • This mechanism makes me wonder whether another mechanism, involving the solar wind / magnetic field and a planetary magnetic field or ionosphere, might also produce a detectable radio signature.

  • > The search for 'Pandora' has begun.

    Well done. As long as I don't have to sit through the movie again...

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