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How Gaseous, Neptune-Like Planets Can Become Habitable

An anonymous reader writes: Life as we know it requires small, rocky planets. The gas giants of our solar system aren't habitable (to our knowledge), but a research team has discovered that smaller, Neptune-like planets can be transformed into gas-free, potentially habitable worlds with a little help from red dwarf stars. Such planets are usually formed far out in a planetary system, but tidal forces can cause them to migrate inward. When they reach the habitable zone of their host star, they absorb far larger amounts of x-ray and ultraviolet radiation. This can eventually boil off most of the the gas atmosphere, leaving behind the core: a small, rocky world capable of supporting life.

65 comments

  1. An X-Ray baked hellscape sound perfect by jandrese · · Score: 4, Insightful

    This sounds like a great way to make a Mercury type planet, but I'm not so sure it will be so great at making a place you would want to live.

    --

    I read the internet for the articles.
    1. Re:An X-Ray baked hellscape sound perfect by Anonymous Coward · · Score: 0

      In the spirit of Clarke: But, but the diamonds everywhere!

    2. Re:An X-Ray baked hellscape sound perfect by Tablizer · · Score: 1

      What makes you say they are targeting Mercury-like planets?

    3. Re:An X-Ray baked hellscape sound perfect by TWX · · Score: 1

      Mercury is not in the habitable zone. Being in the habitable zone is the first requirement after having a planet itself.

      --
      Do not look into laser with remaining eye.
    4. Re:An X-Ray baked hellscape sound perfect by Noah+Haders · · Score: 1

      yes but even if it were in a habitable zone, it would still be drenched in xray and UV, so I'm not sure how habitable it would really be...

    5. Re:An X-Ray baked hellscape sound perfect by TWX · · Score: 1

      But a planet that starts out further from its star than the habitable zone, and migrates into the habitable zone, wouldn't necessarily burn up like Mercury either.

      --
      Do not look into laser with remaining eye.
  2. Wouldn't it be easier by rossdee · · Score: 2

    Wouldn't it be easier to terraform the moons of gas giants

    1. Re:Wouldn't it be easier by Anonymous Coward · · Score: 1

      No. Gas giants have hellacious radiation belts that would sterilize any of their moons very quickly and prevent any type of radio communications. Basically, it'd be like trying to set up camp inside the reaction chamber in the nuclear power plant.

    2. Re:Wouldn't it be easier by itzly · · Score: 1

      Nobody's talking about terraforming, especially not when it involves moving around a Neptune sized planet.

    3. Re:Wouldn't it be easier by Infiniti2000 · · Score: 3, Funny

      Took some significant technology improvements in MOO2, that's for sure.

    4. Re:Wouldn't it be easier by dimeglio · · Score: 1

      Can't blame him. Reading the title, first thing I though of was "we can make Neptune habitable." I blame reading comprehension.

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      Views expressed do not necessarily reflect those of the author.
    5. Re:Wouldn't it be easier by Lumpy · · Score: 1

      The is slashdot. Science has no place in speculation!

      --
      Do not look at laser with remaining good eye.
    6. Re:Wouldn't it be easier by FatdogHaiku · · Score: 1

      The is slashdot. Science has no place in speculation!

      Sir, I object to your use of the term "speculation"!
      Here, we do "rampant, mostly uninformed speculation*"!
      * Of course, that's just a guess on my part...

      --
      You have the right to remain sentient. If you give up the right to remain sentient, you will be elected to public office
    7. Re:Wouldn't it be easier by TWX · · Score: 1

      Based on possible Europa missions (Europan?) with an intention to bore down through the ice to look for life in what's expected to be a vast ocean, I don't think that your view is universally shared.

      --
      Do not look into laser with remaining eye.
    8. Re:Wouldn't it be easier by Livius · · Score: 2

      Ten km of ice can help with the radiation, so Europa is likely quite capable of supporting life. But Europa is not *habitable* by human standards.

    9. Re:Wouldn't it be easier by dryeo · · Score: 1

      Titan, a moon of a gas giant named Saturn, is not orbiting in a hellacious radiation belt and if it was warmed up might be habitable.
      Even most of Jupiters satellites are far enough away from Jupiter that the radiation would not be hellacious though in our system all the nice sized ones are too close.

      --
      https://en.wikipedia.org/wiki/Inverted_totalitarianism
    10. Re:Wouldn't it be easier by toddestan · · Score: 1

      Well, since moons of gas giants tend to be tidally locked, couldn't you just live on the side that faces away from the planet?

  3. next daft question by ihtoit · · Score: 4, Interesting

    Did Earth once possess a much larger (Neptune-sized or even larger?) atmosphere, maybe sometime way before the Hadean period? I can see the hydrogen/helium literally boiling off by a warming sun, leaving behind the heavier gases. Maybe we're looking at what Earth has now completely in the wrong way, considering that even at 430km the ISS is being slowed by atmospheric drag - common assumption has it that "Space" occurs at what, shy of 100km? This Karman line isn't a solid boundary with Space above and Air below, it's a convenient mark on a piece of paper.

    --
    Political debates have me rolling my eyes so much I think I got optical whiplash. I should sue. - Foamy The Squirrel
    1. Re:next daft question by Anonymous Coward · · Score: 0

      Certainly a thought... In fact the huge pressures that a massive atmosphere would have applied to the core (current earth surface) could even give legitimacy to those crazy sounding expanding earth theorists...(https://www.youtube.com/watch?v=7kL7qDeI05U)

    2. Re:next daft question by retroworks · · Score: 1

      On the contrary, at the current rate of increase of smog production, Earth is going to transform into a gas planet.

      --
      Gently reply
    3. Re:next daft question by Tablizer · · Score: 1, Offtopic

      at the current rate of increase of smog production, Earth is going to transform into a gas planet

      Fitting: Uranus created by your anus. Or perhaps rename it Ouranus after we fuck our planet up.

    4. Re:next daft question by TWX · · Score: 1

      Maybe we're looking at what Earth has now completely in the wrong way, considering that even at 430km the ISS is being slowed by atmospheric drag - common assumption has it that "Space" occurs at what, shy of 100km?

      Neptune's radius is about 25,000Km. Earth's radius plus the altitude of the ISS is about 6800Km. That's an awful lot of volume to burn-off.

      --
      Do not look into laser with remaining eye.
    5. Re:next daft question by ihtoit · · Score: 1

      luckily hydrogen and helium aren't that dense.

      --
      Political debates have me rolling my eyes so much I think I got optical whiplash. I should sue. - Foamy The Squirrel
    6. Re:next daft question by Noah+Haders · · Score: 1

      On the contrary, at the current rate of increase of smog production, Earth is going to transform into a gas planet.

      smog has been going down in the US for 3 decades. in china it is going up, however.

  4. Necessary but not sufficient by Anonymous Coward · · Score: 1

    Or would it boil off just enough of the atmosphere to turn it in to a Venusian hell hole?

    1. Re:Necessary but not sufficient by nucrash · · Score: 1

      Venus would actually be pretty awesome if we managed to perfect carbon capture technology. Though we still have to deal with the problem of Venus being tidally locked. Yeah, not sure where I was going with this.

      To the Atmosphere. Balloons will be our savior on the dark side of Venus. :)

      --
      Place something witty here
    2. Re:Necessary but not sufficient by Neil+Boekend · · Score: 1

      You also have to remove the SO2, the HCl and the HF.
      Honestly, the tidal locking is not a major problem, it just limits the size of the possible habitable range. The atmosphere is the main problem.

      --
      Well, I might have a way, but it only works on a semi spherical planet in a vacuum.
  5. Gas giants by XxtraLarGe · · Score: 1, Funny

    The gas giants of our solar system aren't habitable (to our knowledge)

    Pfft! You obviously haven't seen Jupiter Ascending yet! Then again neither have it, but that's beside the point.

    --
    Taking guns away from the 99% gives the 1% 100% of the power.
  6. ahhh! by slashmydots · · Score: 1

    Jupiter is going to crash into us! Everybody RUN!

    1. Re:ahhh! by Jason+Levine · · Score: 1

      No, no, no. It's just going to align with us and make it so we can jump and stay aloft for five minutes. I know it's true because I read it online somewhere.

      --
      My sci-fi novel, Ghost Thief, is now available from Amazon.com.
  7. Cloud Cities? by JoeDuncan · · Score: 1

    Aren't the atmospheres on gas giants so thick and dense that we could make "Cloud Cities" that float on top of the thickest/densest parts of the atmosphere?

    1. Re:Cloud Cities? by Anonymous Coward · · Score: 0

      No, that's on Venus.

    2. Re:Cloud Cities? by jandrese · · Score: 1

      Depending on your definition, you could do that on Earth. In fact it is probably easier on Earth because you don't have 200kph winds gusting up to 400kph.

      --

      I read the internet for the articles.
    3. Re:Cloud Cities? by toddestan · · Score: 1

      Theoretically this is possible on the outer three gas giants. As Jupiter goes, it's gravity is far too strong, plus it has the most intense radiation. So you would want to set up shop on one of the three outer gas giants. Gravity on the outer gas giants is close to Earth's, about 1 g for all three of them. There are actually layers of their atmospheres with Earth-like temperatures, but they are low in the atmosphere where the pressure is extremely high (we're talking about enough to liquidity hydrogen) so you'd want to be higher up. It's pretty cold in the upper layers, plus you're far away from the sun. Venus is probably a better target for a cloud city - about 50km up the atmospheric pressure about 1 atmosphere, temperature is about 0C, gravity is about 1G, and plenty of sun during the day. Plus the atmosphere is mostly CO2, which is denser than breathable air, so a balloon full of breathable air would float on Venus.

  8. 'Death' Star was just a terraforming laser by Anonymous Coward · · Score: 0

    That must be how Vader and the Sith were able to rationalize to the Senate to get the Death Star built. The laser was meant to be used to boil off the gasses by having them absorb the X-Ray and UV laser light... but it could be used to destroy planets at the highest setting.

    1. Re:'Death' Star was just a terraforming laser by war4peace · · Score: 1

      Star Wars nerd here: The Star Wars Universe is so filled with habitable planets that many which would have required much smaller terraforming efforts were left alone without so much as a closer look. One of the foremost examples would be Dagobah. But I digress :)

      --
      ...gis sdrawkcab (usually not responding to ACs; don't bother posting as AC)
    2. Re:'Death' Star was just a terraforming laser by WhiplashII · · Score: 3, Interesting

      Another Star Wars reader: it actually explains this in one of the books by Stackpole - The Emperor created the so-called "death stars" for rapid mineral extraction from planet sized objects. It was only meant for peaceful uses, until Rebel Terrorists took the first one and blew up Alderaan; the Emperor then had that one destroyed. The second one was almost taken over by the Rebel Terrorists and the Emperor ordered it destroyed, at the cost of his own life.

      It must be true, it was in a museum on Coruscant.

      --
      while (sig==sig) sig=!sig;
    3. Re:'Death' Star was just a terraforming laser by TWX · · Score: 1

      Or, it was a literal plot-device, and it was created solely for the story to advance, without any real concern for backstory... Given that the original Star Wars was written to be like a middle-episode of a serialized show from the movies, like a Buster Crabbe Flash Gordon type of show, there wouldn't be a whole lot of backstory necessary in order to enjoy the show.

      --
      Do not look into laser with remaining eye.
  9. Planetary migration due to tidal forces? by Anonymous Coward · · Score: 0

    What is that all about? From what I've read the earth's moon is currently moving away from the earth, not closer. So wouldn't the same forces affect the migration of planets once their environs are cleared of dust, gas and planetismals?

    1. Re:Planetary migration due to tidal forces? by dotancohen · · Score: 1

      What is that all about? From what I've read the earth's moon is currently moving away from the earth, not closer. So wouldn't the same forces affect the migration of planets once their environs are cleared of dust, gas and planetismals?

      The tidal forces bend and stretch the planet. This results in friction and ultimately, heat.

      As soon as you hear the word "heat", you should immediately start looking for places to drain the energy from. In this case, it is orbital velocity that is shed, which brings the planet in closer to the star.

      --
      It is dangerous to be right when the government is wrong.
    2. Re: Planetary migration due to tidal forces? by Zorpheus · · Score: 1

      Tidal forces are slowing down rotation, until rotation is locked to orbit. Then they don't cause deformation anymore. Do they really also affect the orbit? Certainly not when rotation is locked.

    3. Re: Planetary migration due to tidal forces? by dotancohen · · Score: 1

      The fine article suggests that it does in fact affect orbit. Truth be told, it is the first time that I hear this, and _perhaps_ it is the case for gaseous worlds, for which slowing down the rotation is not as straightforward as for rocky worlds.

      I've asked on space.SE, your input and comments are welcome on that discussion:
      http://space.stackexchange.com...

      --
      It is dangerous to be right when the government is wrong.
  10. Bespin! by Anonymous Coward · · Score: 0

    No problem, send Lando Calrissian to set up Cloud City!

    1. Re:Bespin! by war4peace · · Score: 1

      Star Wars nerd here: Cloud City wasn't really floating all by itself, it used city-wide repulsors to do so. Around 36K of them IIRC.

      --
      ...gis sdrawkcab (usually not responding to ACs; don't bother posting as AC)
    2. Re:Bespin! by TWX · · Score: 1

      Oooh boy, there's nothing I like more than relying on active equipment in order to remain alive...

      --
      Do not look into laser with remaining eye.
  11. Hmmm by Anonymous Coward · · Score: 0

    And yet if you suggest converting the Sun into a red giant then people call you mad.

  12. Terrraforming by aardvarkjoe · · Score: 1, Funny

    Apparently the secret to creating a habitable world is to remove the cloud of gas that surrounds Uranus?

    --

    How can we continue to believe in a just universe and freedom to eat crackers if we have no ale?
  13. Can we test on Jupiter? by Dareth · · Score: 3, Funny

    "This can eventually boil off most of the the gas atmosphere, leaving behind the core: a small, rocky world capable of supporting life.'

    So after nano tech fiber makes space elevators possible, we can then work on a planet towing device to drag Jupiter in to the sweet spot where it will boil away and leave us Jupiter-2, Rocky Core Edition? Oh wait, first we need to drag a Red Dwarf star into our solar system. Damnable prerequisites.

    --

    I only look human.
    My mother is a halfling and my dad is an ogre, so that makes me an Ogreling
    1. Re:Can we test on Jupiter? by rossdee · · Score: 1

      " first we need to drag a Red Dwarf star into our solar system."

      We already have a few Red Dwarf stars here, like Craig Charles and Chris Barrie

    2. Re:Can we test on Jupiter? by Anonymous Coward · · Score: 0

      I'd be perfectly fine with launching both of them to Jupiter...

  14. Velikovsky (almost) strikes again! by Daetrin · · Score: 1

    Looks like another example of how _some_ of Immanuel Velikovsky's ideas, such as those in Worlds in Collision, were actually plausible and scientifically interesting, at least at a basic level. It's too bad he felt it was necessary to sabotage himself by compressing all of his ideas together into an implausibly complex series of events taking place over an implausibly short timeline in order to make a kind of historical conspiracy theory.

    --
    This Space Intentionally Left Blank
  15. How convenient by Tablizer · · Score: 2

    Notice how the article used Neptune instead of Uranus as an example.

  16. Old idea by Anonymous Coward · · Score: 0

    I can't believe they are just figuring this out. I remember thinking this was possible decades ago as a child.

    It just goes to show that everybody is stupid except for me.

    1. Re:Old idea by Tablizer · · Score: 1

      The general concept is one thing, doing the math and science to show it's naturally feasible is another.

  17. Boil a gas? by vanyel · · Score: 1

    How do you boil off something already a gas? Sounds like we need a term for "heating a gas to the point molecules exceed escape velocity"...

  18. magnetic Field? by anwyn · · Score: 1

    Yes, but would a planet created in this way have a magnetic field? Another Mars won't help.

    1. Re:magnetic Field? by dryeo · · Score: 1

      Neptune has a pretty powerful magnetic field though it is a bit weird as it is off centre rather then going through the core.

      --
      https://en.wikipedia.org/wiki/Inverted_totalitarianism
  19. Why would you need an external energy source? by Ihlosi · · Score: 1

    Aren't the atmospheres of Neptune-like planets made mostly of fusion fuels? The atmosphere itself could be used as a fuel source to strip the planet of gas and ice.

    1. Re:Why would you need an external energy source? by Neil+Boekend · · Score: 1

      According to wikipedia:

      Composition
      80 ± 3.2% hydrogen (H2)
      19 ± 3.2% helium (He)
      1.5 ± 0.5% methane (CH4)
      ~0.019% hydrogen deuteride (HD)
      ~0.00015% ethane (C2H6)
      Ices:
      ammonia (NH3)
      water (H2O)
      ammonium hydrosulfide (NH4SH)

      methane ice (?) (CH4â5.75H2O)

      So yes, there is a lot of hydrogen. However, to burn hydrogen you need oxygen. Where are you going to get that amount of oxygen?

      --
      Well, I might have a way, but it only works on a semi spherical planet in a vacuum.
    2. Re:Why would you need an external energy source? by Ihlosi · · Score: 1
      However, to burn hydrogen you need oxygen.

      For chemical combustion, maybe. I was talking about nuclear fusion. Any civilization capable of interplanetary or even interstellar travel has probably already developed the technology to harness artificial nuclear fusion as an energy source.

      So, terraforming a Neptune-like world would merely be a matter of building enough reactors and waiting long enough.

    3. Re:Why would you need an external energy source? by Neil+Boekend · · Score: 1

      Sorry, I misread fusion as fossil.

      --
      Well, I might have a way, but it only works on a semi spherical planet in a vacuum.
  20. What about life NOT as we know it? by fygment · · Score: 1

    Is there some kind of reason we want to find things just like us?
    Isn't that kind of boring?

    --
    "Consensus" in science is _always_ a political construct.
    1. Re:What about life NOT as we know it? by stardaemon · · Score: 1

      Is there some kind of reason we want to find things just like us? Isn't that kind of boring?

      We don't just want to find things that are like us.
      It's just that's it easier to look for, as we have a good idea what to look for.

      --
      The only way to stay sane in an insane world, is to be mad yourself...