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posted by cmn32480 on Saturday October 22 2016, @04:23PM   Printer-friendly
from the weebles-wobble-but-they-don't-fall-down dept.

Arthur T Knackerbracket has found the following story:

The massive hypothetical object, which supposedly looms at the edge of our solar system, has been invoked to explain the strange clustering of objects in the Kuiper belt and the unusual way they orbit the Sun.

Now Planet Nine predictors Konstantin Batygin and Mike Brown of Caltech, along with graduate student Elizabeth Bailey, offer another piece of evidence for the elusive sphere's existence: It adds "wobble" to the solar system, they say, tilting it in relation to the sun.

"Because Planet Nine is so massive and has an orbit tilted compared to the other planets, the solar system has no choice but to slowly twist out of alignment," lead author Bailey said in a statement.

Before we go any further, a caveat about Planet Nine: It's purely theoretical at this point. Batygin and Brown predict its existence based on unusual perturbations of the solar system that aren't otherwise easily explained. (This is the same technique scientists used to find Neptune.) But the history of astronomy is rife with speculation that is never borne out: The same guy who correctly predicted the existence of Neptune also believed that a planet he called Vulcan was responsible for the wobble of Mercury. That "discovery" caused the astronomy world to waste years looking for something that wasn't there. (Mercury's wobble was eventually explained by the theory of general relativity.)

But the evidence offered by Batygin and Brown is compelling. When the pair announced their find in January, planetary scientist Alessandro Morbidelli of the Côte d'Azur Observatory in Nice, France, told The Washington Post: "I don't see any alternative explanation to that offered by Batygin and Brown."

"We will find it one day," he added. "The question is when."

Planet Nine's angular momentum is having an outsized impact on the solar system based on its location and size. A planet's angular momentum equals the mass of an object multiplied by its distance from the sun, and corresponds with the force that the planet exerts on the overall system's spin. Because the other planets in the solar system all exist along a flat plane, their angular momentum works to keep the whole disk spinning smoothly.

Planet Nine's unusual orbit, however, adds a multi-billion-year wobble to that system. Mathematically, given the hypothesized size and distance of Planet Nine, a six-degree tilt fits perfectly, Brown says.


Original Submission #1; Original Submission #2

Related Stories

NASA Website Allows Public to Search WISE Data for Nearby Objects and Planet Nine 6 comments

NASA is collaborating with Zooniverse to allow the public to search WISE data for "nearby" rogue planets, brown dwarfs, and Planet Nine:

NASA is inviting the public to help search for possible undiscovered worlds in the outer reaches of our solar system and in neighboring interstellar space. A new website, called Backyard Worlds: Planet 9, lets everyone participate in the search by viewing brief movies made from images captured by NASA's Wide-field Infrared Survey Explorer (WISE) mission. The movies highlight objects that have gradually moved across the sky.

"There are just over four light-years between Neptune and Proxima Centauri, the nearest star, and much of this vast territory is unexplored," said lead researcher Marc Kuchner, an astrophysicist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "Because there's so little sunlight, even large objects in that region barely shine in visible light. But by looking in the infrared, WISE may have imaged objects we otherwise would have missed."

Backyard Worlds: Planet 9.

Previously: No Evidence for 'Planet X', says NASA - "[No] object the size of Saturn or larger exists out to a distance of 10,000 astronomical units (AU), and no object larger than Jupiter exists out to 26,000 AU."
NASA's WISE Spacecraft Discovers Most Luminous Galaxy in Universe
NASA's NEOWISE Mission Finds 72 Additional Near-Earth Objects
Two New Kuiper Belt Objects Boost the Case for "Planet Nine"
The Mysterious 'Planet Nine' Might be Causing the Whole Solar System to Wobble


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  • (Score: 0) by Anonymous Coward on Saturday October 22 2016, @04:38PM

    by Anonymous Coward on Saturday October 22 2016, @04:38PM (#417600)

    We have high resolution cameras available now. Take pictures of the stars over successive days, and looking for something that moved, should be rather easy. "Planet 9" would have to orbit the Sun like the rest of the planets.

    • (Score: 2) by takyon on Saturday October 22 2016, @05:15PM

      by takyon (881) <takyonNO@SPAMsoylentnews.org> on Saturday October 22 2016, @05:15PM (#417607) Journal

      http://www.space.com/34455-planet-nine-discovery-coming-soon.html [space.com]

      Planet Nine's days of lurking unseen in the dark depths of the outer solar system may be numbered. The hypothetical giant planet, which is thought to be about 10 times more massive than Earth, will be discovered within 16 months or so, astronomer Mike Brown predicted.

      "I'm pretty sure, I think, that by the end of next winter — not this winter, next winter — I think that there'll be enough people looking for it that … somebody's actually going to track this down," Brown said during a news conference Wednesday (Oct. 19) at a joint meeting of the American Astronomical Society's Division for Planetary Sciences (DPS) and the European Planetary Science Congress (EPSC) in Pasadena, California. Brown said that eight to 10 groups are currently looking for the planet. At the "next one of these [DPS-EPSC meetings], we'll be talking about finding Planet Nine instead of just looking for it," added Brown, who's based at the California Institute of Technology (Caltech) in Pasadena.

      Problems finding it include:

      • It's faint
      • It's far away
      • The inclination is estimated to be higher than the known planets
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      • (Score: 2) by Grishnakh on Saturday October 22 2016, @09:50PM

        by Grishnakh (2831) on Saturday October 22 2016, @09:50PM (#417672)

        Wait a minute... so something that's only a mere 10x the mass of the Earth is supposed to be causing such an obvious effect, even though it's located so far away? TFS was talking about a "massive" planet. 10x Earth size is not "massive", it's kinda small. Jupiter is massive, and it's thousands of times the mass of the Earth. Earth, Mars, Venus, etc. are all very small planets when compared to Jupiter, Neptune, Saturn, and Uranus. When someone talks about a "massive" planet, that's what I think of. And I can't imagine how something the size of Jupiter could possibly go undetected unless it's several light-years away. But something 10x the size of Earth? That's easy to understand; we have a hard time resolving Pluto at this distance, and it's not even that far away compared to the other Kuiper Belt objects which have been detected in recent years.

        • (Score: 3, Informative) by takyon on Saturday October 22 2016, @09:56PM

          by takyon (881) <takyonNO@SPAMsoylentnews.org> on Saturday October 22 2016, @09:56PM (#417677) Journal

          It's causing an obvious effect... on objects that weren't known to exist 5-20 years ago.

          Turn on your brain and give them some credit.

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        • (Score: 2) by takyon on Saturday October 22 2016, @10:03PM

          by takyon (881) <takyonNO@SPAMsoylentnews.org> on Saturday October 22 2016, @10:03PM (#417680) Journal

          And I can't imagine how something the size of Jupiter could possibly go undetected unless it's several light-years away. But something 10x the size of Earth?

          10x mass != 10x "size". And it is an estimate, subject to change.

          WISE [wikipedia.org] has already looked for Neptune and Jupiter sized planets:

          WISE was not able to detect Kuiper belt objects, because their temperatures are too low. It was able to detect any objects warmer than 70–100 K. A Neptune-sized object would be detectable out to 700 AU, a Jupiter-mass object out to 1 light year (63,000 AU), where it would still be within the Sun's zone of gravitational control. A larger object of 2–3 Jupiter masses would be visible at a distance of up to 7–10 light years.

          Neptune is 17.147 Earth masses. Planet Nine is theorized to be a "mini-Neptune" of around 10 Earth masses and could be anywhere from 200 to 1200 AU away from the Sun. So it was probably not within WISE's abilities to detect.

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  • (Score: 3, Interesting) by bzipitidoo on Saturday October 22 2016, @06:08PM

    by bzipitidoo (4388) on Saturday October 22 2016, @06:08PM (#417621) Journal

    What are the odds that there is no single planet 9, instead there is a double planet out there? After all, aren't binary star systems more common than singles? Maybe being much further out makes that more likely?

    Sure would make a fun mess of a lot of rather dogmatic ideas, such as the definition of a planet. Probably mess up a hypothesis that there is a 5th gas giant which was ejected early in the solar system's history. Might make it harder to find. I can imagine astronomers tearing their hair out trying to find planet 9 and failing because it isn't one massive object, it's two smaller, dimmer objects. It's not like a double planet is unprecedented-- the Earth and Moon can be considered such, as well as Pluto and Charon.

    • (Score: 0) by Anonymous Coward on Saturday October 22 2016, @06:59PM

      by Anonymous Coward on Saturday October 22 2016, @06:59PM (#417631)

      If there are two planets out there that are close enough to each other to cause their gravitational effects to appear as a single planet wouldn't their gravitational pulls cause them to collide?

      • (Score: 3, Informative) by Arik on Saturday October 22 2016, @07:19PM

        by Arik (4543) on Saturday October 22 2016, @07:19PM (#417636) Journal
        "If there are two planets out there that are close enough to each other to cause their gravitational effects to appear as a single planet wouldn't their gravitational pulls cause them to collide?"

        Not necessarily. The Terra-Luna system is actually slowly expanding, for example.
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      • (Score: 2) by HiThere on Saturday October 22 2016, @07:32PM

        by HiThere (866) Subscriber Badge on Saturday October 22 2016, @07:32PM (#417640) Journal

        No. Things in orbit don't collide unless their orbits get disturbed...and usually not then.

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        • (Score: 2) by WalksOnDirt on Sunday October 23 2016, @05:52AM

          by WalksOnDirt (5854) on Sunday October 23 2016, @05:52AM (#417766) Journal

          Two objects orbiting each other cannot be stable[1]. The rotational energy can cause their mutual orbit to contract or expand (like the Earth, Moon system), and gravitational radiation will act to contract their orbit.

          It doesn't seem to be known whether the Earth and Moon would separate until they move into different orbits or, after they reach some maximal separation, shrink their orbits until they end up in collision; except that we know that the Sun will go red giant before then.

          [1]If they are the only objects in the Universe there might be an exception.

          • (Score: 2) by HiThere on Sunday October 23 2016, @06:23PM

            by HiThere (866) Subscriber Badge on Sunday October 23 2016, @06:23PM (#417907) Journal

            A reasonable argument, given a long enough period of time, but it ignores that they can both be tidally locked. (Improbable, but so is the pair being in isolation long enough for tidal effects to break the orbit...unless one is quite massive, and the other reasonably close. Even binary star systems have been observed being broken up by external effects.

            That said, a three body system makes things a lot more complex, and small effects can cascade...given ENOUGH time. But in orbital mechanics enough is usually either quite a brief period, or quite a long period. The intermediate cases seem to be comparatively rare.

            Then again, if you wait long enough the protons may evaporate....well, ok, that's an unproven theory, and if they do it's REALLY slowly, but nothing seems to be really permanent. So if we want to call anything a stable orbit, then most planet/moon systems, or even asteroid/moon systems seem to qualify. They are more likely to be disrupted by external events than by orbital decay.

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            • (Score: 2) by WalksOnDirt on Sunday October 23 2016, @11:17PM

              by WalksOnDirt (5854) on Sunday October 23 2016, @11:17PM (#417985) Journal

              ...but it ignores that they can both be tidally locked

              That wasn't ignored. In that case they radiate gravitational waves until they collide. What was ignored was friction with any gas in the space, but that entails (at least) a third object, which I implicitly assumed would not matter. For smaller objects than stars it is likely to be more important than gravity waves.

              • (Score: 2) by HiThere on Monday October 24 2016, @05:30AM

                by HiThere (866) Subscriber Badge on Monday October 24 2016, @05:30AM (#418048) Journal

                ...but it ignores that they can both be tidally locked

                That wasn't ignored. In that case they radiate gravitational waves until they collide. What was ignored was friction with any gas in the space, but that entails (at least) a third object, which I implicitly assumed would not matter. For smaller objects than stars it is likely to be more important than gravity waves.

                Are you sure about that? I thought that after they both became tidally locked they stopped emitting gravity waves. Of course, if only one of them were tidally locked, the system would keep emitting gravity waves, and that's the more common occurrence. The easiest way to get it to happen such that they were both tidally locked would seem to be a comet/asteroid with two pieces held together by some ice having the ice sublime as it warmed up. ... and that already brings in a third body.

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                • (Score: 3, Informative) by WalksOnDirt on Monday October 24 2016, @06:28AM

                  by WalksOnDirt (5854) on Monday October 24 2016, @06:28AM (#418054) Journal

                  Any[2] two objects orbiting each other will emit gravity waves. Their rotation has nothing to do with it. For anything of stellar mass or less it will take an unreasonably long time, though.

                  If two objects are not tidally locked their orbits will expand or shrink until they are tidally locked or, if there is enough energy available in their rotation, they collide or escape each other. This has nothing to do with gravity waves, and is caused by tides.

                  Mutually tidally locked objects are easy to produce. Pluto and Charon form one such pair.

                  [2]Electrons don't really orbit nuclei.

    • (Score: 2) by takyon on Saturday October 22 2016, @07:18PM

      by takyon (881) <takyonNO@SPAMsoylentnews.org> on Saturday October 22 2016, @07:18PM (#417635) Journal
      • There is no agreement that Earth-Moon is a binary/double system [wikipedia.org], and there are a few arguments against it.
      • Do moons or binaries make the detection that much harder? I guess it could by lowering the temperature of both compared to a single, larger gas planet. What it could do is make diameter estimates inaccurate, especially if the imagery has a low resolution.
      • Large binaries are possible [space.com], but so are collision and ejection.

      The possibility of a Planet Nine with moons is interesting since it could allow its mass to be determined with more accuracy, and if Planet Nine is a mini-Neptune, it gives us a new opportunity to find large moons close to home. The largest known satellite is Ganymede, and it has just 2.5% of Earth's mass. Tidal heating could mean that moons around a Planet Nine might have underground oceans.

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      • (Score: 2) by bzipitidoo on Monday October 24 2016, @10:07PM

        by bzipitidoo (4388) on Monday October 24 2016, @10:07PM (#418301) Journal

        I expect Planet 9, whether single or binary, to have lots of moons, same as our gas giants.

        We haven't settled on a definition for binary planet. Very popular is "barycenter is not within the larger body", but that has problems. Would like a definition that does not change the status of a binary system as it evolves, and the barycenter of Earth-Moon is moving as the Moon moves outward, and will eventually be outside Earth's body. Also would like a definition that is independent of position in a solar system and size of the star orbited. Binary star system is easy in part because star is fairly easy. A red dwarf orbiting a blue hypergiant is still a binary star system. Relative mass can make a simple definition. If the mass of the smaller body is at least some significant percentage of the mass of the larger body, then it's a double planet. Just what that percentage should be is a problem-- 50%? 10%? Suppose Earth was in orbit about Jupiter, would that demote Earth to the status of a moon? Suppose Ganymede was in orbit about the sun, would it be a planet then? Ganymede is larger diameter than Mercury, however, Mercury is much denser and has more mass. At any rate, if relative mass an acceptable way to define double planet, that percentage can be decided almost independently of the definition of a planet.

    • (Score: 2) by HiThere on Saturday October 22 2016, @07:30PM

      by HiThere (866) Subscriber Badge on Saturday October 22 2016, @07:30PM (#417639) Journal

      A friend of mine who used to be quite technical as well as a visual astronomer, and who still follows astronomical news has a very unusual suggestion with a possibly unpleasant corollary.

      He suggests that we've already seen it. That it's one of the really distant objects seen beyond Pluto which has a reddish color...which he suggests might be the color of a white dwarf star that's cooled for a LONG time. The thing is, these stars slowly accrete matter without visible change until they pass a crucial threshold, at which point they become a supernova. If so, it might be very important that we start devoting energies to self-sufficient space habitats...ones that don't depend on the sun for power, and which can thus slowly migrate away. The resources out beyond the Oort clouds are pretty scant, so there's a lot of preparatory work that needs to be done. Fission power might be sufficient, though fusion would be better, and there's not only a need for a (nearly) closed eco-system, there's also the need for better ion-rockets, etc,

      Most of the things can be re-purposed from things that are more immediately useful for in-system work. But the first thing to do is to get a better idea of the weight of that object. IIUC it is known to have a satellite, so that shouldn't take long...especially on this time scale.

      N.B.: My friend is rather old, and has started to get a bit confused, so a good question would be "Is that red distant object in the same direction that planet IX needs to be?". This, however, would better be answered by someone who's actively an astronomer. The odds are the answer is "no", of course, but the speculation is sufficiently important that it would be nice if it were investigated.

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      • (Score: 0) by Anonymous Coward on Saturday October 22 2016, @08:05PM

        by Anonymous Coward on Saturday October 22 2016, @08:05PM (#417645)

        one of the really distant objects seen beyond Pluto which has a reddish color

        Is there a searchable name for these objects?

      • (Score: 2) by takyon on Saturday October 22 2016, @08:38PM

        by takyon (881) <takyonNO@SPAMsoylentnews.org> on Saturday October 22 2016, @08:38PM (#417654) Journal

        Even if humanity never attempts to build a Dyson swarm or travel to another star, there is a lot more real estate in the solar system than we used to know about, and a lot more to discover.

        If Planet Nine exists, it might be possible to land on its surface, and it might have lots of moons (Pluto has 5, Jupiter has 67, Neptune has 14). It is described as a mini-Neptune at its theorized mass.

        In the long term, we could put bases or colonies on the Moon, Mars, Venus, Mercury [wikipedia.org], Pallas, Ceres, Vesta, Ganymede, Callisto, Europa, Io, Titan, Enceladus, Titania, Triton, etc. There are other large asteroids and moons I didn't list, and once we can cope with the coldest ones, any TNOs/KBOs should be fair game. Pluto, Charon, Eris, Sedna, Makemake, Haumea, Quaoar, Orcus, Salacia, Varuna, Ixion, etc. Many of them have small moons, for what that's worth. Some of the TNOs have up to 0.1g of gravity. Our ACs have complained about the habitability of lower gravity rocks a lot lately, but 0.083g (Eris) or 0.376g (Mars) beats microgravity.

        There are more TNOs to discover that are far closer than the Oort cloud. Some of the undiscovered TNOs could be as big as Mars.

        NASA has thought of concept probes [wikipedia.org] that could travel over 10 AU per year (1000 AU in less than a century). Many of the large known TNOs are just 50-100 AU away. We may have more options for getting around in the future, such as fusion propulsion instead of RTG + ion engines.

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        • (Score: 2, Disagree) by Grishnakh on Saturday October 22 2016, @09:57PM

          by Grishnakh (2831) on Saturday October 22 2016, @09:57PM (#417678)

          Why would anyone want to live on a colony on one of these worlds? They're very far from the Sun, they're cold, they're small, they have no atmosphere or at least nothing breathable, and they have extremely insufficient gravity. What is the point, unless you really need them for mining (in which case you'd probably do better just grabbing Earth-crossing asteroids, or ones in the Belt since it's so much closer; additionally, most of this work could be done by remotely-operated vehicles).

          If people need a new place to live, the answer isn't trying to colonize some small, dead moon, it's to build space-based habitats. A very large space station that rotates can be set to have whatever gravity you want, and can be built to have whatever habitat inside you want. If you have the technology to build a sealed habitat on Ceres or Titan or wherever, you have the technology to build a sealed habitat in Earth orbit or at a Lagrangian point, close enough to visit Earth from time to time, and your space habitat will actually have proper gravity, unlike something on another world.

          • (Score: 2) by takyon on Saturday October 22 2016, @10:21PM

            by takyon (881) <takyonNO@SPAMsoylentnews.org> on Saturday October 22 2016, @10:21PM (#417684) Journal

            Why would anyone want to live on a colony on one of these worlds?

            Normie spotted. Someone will be content to live indoors on a colony indefinitely, with meager means. We already have those types of humans, they are called NEETs.

            Advancements in propulsion will allow much faster travel to Pluto et al. than is currently possible. Settlers are not necessarily condemned to live there forever.

            We are also talking about a long timescale. If it doesn't make sense to settle icy moons and dwarf planets in the next hundred years, it can be done in the next five hundred years. They will still be there, waiting for us to build the appropriate technologies and get the price down.

            Also, there are long-term prospects for terraforming in some of the cases.

            extremely insufficient gravity

            As long as your eyes are not popping out of your skull, it is not insufficient. 0.05g could be a lot better than microgravity.

            the answer isn't trying to colonize some small, dead moon, it's to build space-based habitats

            Those "dead" moons are already out there, and always will be. They have orders of magnitude more mass than space-based habitats, and usable resources including water ice. You can have both the space-based habitat and the dwarf planet base if the economics allow it.

            If you have the technology to build a sealed habitat on Ceres or Titan or wherever, you have the technology to build a sealed habitat in Earth orbit or at a Lagrangian point

            And you could also put one in orbit around these moons + planets. Call it an Earth gravity gym. They can orbit very close if there is little or no atmosphere to worry about, and if the escape velocity is low, it won't be hard to travel to and from the station.

            close enough to visit Earth from time to time

            That is not a requirement of a self-sufficient colony/base. If you can't bear to leave Earth behind, then you are free to die there. But don't presume that others have that same need.

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            • (Score: 2) by Grishnakh on Sunday October 23 2016, @04:04AM

              by Grishnakh (2831) on Sunday October 23 2016, @04:04AM (#417742)

              Someone will be content to live indoors on a colony indefinitely, with meager means. We already have those types of humans, they are called NEETs.

              NEETs are unemployed and have no education. What makes you think they never go outside? You don't need a job to go walk around outside. There's tons of homeless people who literally live outside, or in tents.

              Advancements in propulsion will allow much faster travel to Pluto et al. than is currently possible.

              They'll need advances in shielding too, so they don't die of radiation poisoning on the way.

              You still haven't answered my question: why would anyone go to these places, when you can build habitats much closer to the Earth, where there's a lot more sunlight? Where do you think these settlers are going to get power from? More importantly, who's going to pay for all these people to live on Pluto, sitting inside all the time and jerking off?

              Also, there are long-term prospects for terraforming in some of the cases.

              No, there aren't'. Venus and Mars are pretty much the only two places where that's even remotely possible.

              As long as your eyes are not popping out of your skull, it is not insufficient. 0.05g could be a lot better than microgravity.

              Bullshit. The health effects of low gravity are currently unknown for sure because no one's lived on another world for more than a few hours (the Apollo missions). We do know, however, that there's seriously negative health effects to zero-g, as seen in those who have spent considerable time in the ISS. It's quite likely that living in low-g habitats will also have negative health effects.

              They have orders of magnitude more mass than space-based habitats, and usable resources including water ice.

              We can get those things from asteroids much closer to the Earth, and we can do mining operations with remotely-operated vehicles, or possibly small contingents of humans. But that doesn't really give people much of a reason to live in these places; it doesn't take that many people to do mining with advanced technology, and there's no other valid reason to live in these places.

              And you could also put one in orbit around these moons + planets. Call it an Earth gravity gym. They can orbit very close if there is little or no atmosphere to worry about, and if the escape velocity is low, it won't be hard to travel to and from the station.

              You still haven't answered the question of why anyone would want to live in these places. If I can live in an orbital habitat around Pluto or around Earth, why would I pick Pluto? It's just stupid.

              If you can't bear to leave Earth behind, then you are free to die there. But don't presume that others have that same need.

              If you're so anxious to build a base on Pluto, go ahead, just don't ask me to fund it for you. There's no valid economic reason for such a venture.

              • (Score: 0) by Anonymous Coward on Monday October 24 2016, @05:06AM

                by Anonymous Coward on Monday October 24 2016, @05:06AM (#418046)

                Trump's great-great-etc grandson inherited the Presidency of Earth and you want to live as far way as possible.

        • (Score: 2) by HiThere on Sunday October 23 2016, @06:43PM

          by HiThere (866) Subscriber Badge on Sunday October 23 2016, @06:43PM (#417918) Journal

          You're missing my point. As long as humanity is clustered around one Star we have "all our eggs in one basket". It's not a matter of room, though I'd assert that the growth function could use any amount of terrain that could even possibly be present. That's irrelevant, because we're going to *need* to limit growth whatever we do.

          But you also shouldn't judge future habitats by current space-labs. They shouldn't be at all comparable. They'd be more equivalent to a giant arcology. Admittedly archologies are currently an unsolved problem, but we're going to need to solve them anyway unless we impose REALLY strict population controls. Currently cities are inhumane places to live, but they also provide vital services that aren't available elsewhere...and rapid transportation uses lots of energy.

          So think of a space habitat as a city in space. It would need to rotate for gravity. Now your argument is "Nobody would want to spend their life in a city!", but many people do. And your argument is that current city design can't be improved. I disagree.

          OTOH, a habitat in space won't be very libertarian. Sorry, but it's a highly artificial environment in a very dangerous environment, so you can't let people mess with it in unsafe ways. This makes virtual reality very important, probably full immersion virtual reality. This is clearly already being worked on, however, for other reasons. In fact almost all the required technologies are already being worked on for other reasons.

          If we do things right eventually humanity, if not Earth, will be able to survive a nearby supernova. And one WILL eventually happen. There's probably no rush on that score, however, the current problem is insane governments that are juggling thermonuclear bombs. Surviving that is a lot easier, but it still requires a self-sufficient off-planet civilization...preferably one which could survive a large Coronal Mass Ejection.

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          • (Score: 0) by Anonymous Coward on Monday October 24 2016, @02:13PM

            by Anonymous Coward on Monday October 24 2016, @02:13PM (#418144)

            If we do things right eventually humanity, if not Earth, will be able to survive a nearby supernova. And one WILL eventually happen. There's probably no rush on that score, however, the current problem is insane governments that are juggling thermonuclear bombs. Surviving that is a lot easier, but it still requires a self-sufficient off-planet civilization...preferably one which could survive a large Coronal Mass Ejection.

            Note that Supernova events likely already happened in the past. All those problems are a single problem, and solution is one and same: do on Earth what you expect to be needed to do to survive on other planets, i.e. build self-sufficient underground habitats, shielded from surface-level radiation. It is much easier and cheaper to do that here and now then billions of miles away or in the hurry.

      • (Score: 1) by khallow on Saturday October 22 2016, @09:42PM

        by khallow (3766) Subscriber Badge on Saturday October 22 2016, @09:42PM (#417668) Journal

        The thing is, these stars slowly accrete matter without visible change until they pass a crucial threshold, at which point they become a supernova.

        They don't actually do that without visible change. You'd pick up X rays and gamma rays from matter falling onto the surface of the object and if it was doing a lot of accreting, the object would be pretty hot and relatively visible. Further these objects have to accumulate a lot of matter before they could supernova, like a major portion of the Sun. It's not going to find that much matter out beyond Pluto.

        • (Score: 2) by HiThere on Sunday October 23 2016, @06:26PM

          by HiThere (866) Subscriber Badge on Sunday October 23 2016, @06:26PM (#417909) Journal

          You're making assumptions about the speed of accretion. That said, if it had been emitting X-rays would we know? The atmosphere is opaque to X-rays, so only space probes could see it, and they're pretty busy, and if the accretion was slow it wouldn't be bright.

          I *do* consider it quite an unlikely theory, but I *would* be happier if someone would measure the orbital speed of the moon and figure its mass.

          --
          Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
          • (Score: 1) by khallow on Sunday October 23 2016, @07:06PM

            by khallow (3766) Subscriber Badge on Sunday October 23 2016, @07:06PM (#417926) Journal

            You're making assumptions about the speed of accretion.

            In order to generate a supernova, the star has to accumulate more than half a solar mass. There isn't the mass out there in the Oort cloud, including the would-be star or we would have noticed its effects on the other planets. Further, if it was accumulating mass fast enough to become a concern before the Sun turns into a giant star, we would be able to see it now.

            That said, if it had been emitting X-rays would we know?

            We've been observing X rays for somewhere around half a century. Yes, we would know.

            The atmosphere is opaque to X-rays, so only space probes could see it, and they're pretty busy

            Or high altitude observatories on Earth. The atmosphere is not that opaque.

            and if the accretion was slow it wouldn't be bright.

            My point precisely. If the accretion is slow, then we have bigger concerns such as the Earth becoming uninhabitable in a few hundred million to billion years as the Sun turns into a giant star.

  • (Score: 3, Disagree) by slap on Saturday October 22 2016, @08:09PM

    by slap (5764) on Saturday October 22 2016, @08:09PM (#417647)

    I refuse to accept Pluto's demotion. Planet nine is *Pluto*

    So to me, it's "The Mysterious 'Planet Ten'"

    • (Score: 2) by Sulla on Saturday October 22 2016, @08:42PM

      by Sulla (5173) on Saturday October 22 2016, @08:42PM (#417655) Journal

      Nothing I enjoy more than getting together with the other eight (now nine) planets and looking down on someone. Not my fault pluto is so small, and doesn't orbit rigth, and has a moon of similar size to itself. Maybe if Pluto wants to be part of the big boys club it should grow up and fly straight.

      --
      Ceterum censeo Sinae esse delendam
    • (Score: 1) by stretch611 on Saturday October 22 2016, @11:18PM

      by stretch611 (6199) on Saturday October 22 2016, @11:18PM (#417689)

      pluto is a planet...

      https://www.youtube.com/watch?v=CIAXKuxtTsc [youtube.com]

      --
      Now with 5 covid vaccine shots/boosters altering my DNA :P
    • (Score: 1, Flamebait) by Grishnakh on Sunday October 23 2016, @03:52AM

      by Grishnakh (2831) on Sunday October 23 2016, @03:52AM (#417738)

      Then you're an idiot, because if Pluto is a planet, then so is Ceres, making Pluto planet 10, and the total number of planets is several dozen since there's a bunch of similar-sized objects other planets beyond Pluto's orbit.

      • (Score: 1, Redundant) by edIII on Monday October 24 2016, @12:55AM

        by edIII (791) on Monday October 24 2016, @12:55AM (#417998)

        Instead of being trollish about it, why is Pluto not a planet? I mean that seriously. The depth of my knowledge on the subject is that they changed the meaning of planet, or Pluto somehow no longer qualifies.

        It might be more helpful to explain why, and I was hoping some of the people around with greater knowledge might share.....

        --
        Technically, lunchtime is at any moment. It's just a wave function.
        • (Score: 4, Insightful) by dry on Monday October 24 2016, @04:40AM

          by dry (223) on Monday October 24 2016, @04:40AM (#418041) Journal

          https://en.wikipedia.org/wiki/File:Pluto,_Earth_&_Moon_size_comparison.jpg [wikipedia.org] shows the size difference, mass wise Pluto has about 1/5th the mass of the Moon.
          When originally found, it was considered to have the same mass as the Earth (based on assumed affect on Neptune), then Mars, then smaller and smaller, though right off there were arguments that it was really small and not deserving of Planet status.
          The main arguments for it being a Planet are tradition, "I was taught it is a planet so it's a planet" and nationalism, the planet that was discovered by an American and now those horrible foreigners are trying to take it away from us.
          Not very good arguments for it being a planet. There is also precedent, the first few asteroids discovered were at first considered planets, now no-one argues in their favour.
          What arguments are there for it being a planet? Perhaps we should call every rock orbiting the Sun a planet? Or even all the satellites as well?

          • (Score: 2) by edIII on Monday October 24 2016, @08:14PM

            by edIII (791) on Monday October 24 2016, @08:14PM (#418271)

            Thank you.

            --
            Technically, lunchtime is at any moment. It's just a wave function.
  • (Score: 0) by Anonymous Coward on Saturday October 22 2016, @09:31PM

    by Anonymous Coward on Saturday October 22 2016, @09:31PM (#417661)

    GRAVITY HOW DOES IT WORK!

    it is known that there are a number of ort cloud objects that are pluto sized than might just possibly affect calculations of the solar system

    • (Score: 3, Informative) by takyon on Saturday October 22 2016, @09:48PM

      by takyon (881) <takyonNO@SPAMsoylentnews.org> on Saturday October 22 2016, @09:48PM (#417670) Journal

      Let's say the mystery mass is equal to the estimate of 10 Earth masses. That's about 4,500 Pluto masses. Sure, there could be that many large TNOs up to 1000 AU away from the Sun, but they are scattered around. One large object in one place is causing the distortion of orbits. A mini-Neptune-sized Planet Nine would have a much larger effect than Pluto or Mars-sized dwarf planets. Also, the evidence grows as more TNOs are discovered [soylentnews.org].

      --
      [SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
  • (Score: 2) by inertnet on Saturday October 22 2016, @11:01PM

    by inertnet (4071) on Saturday October 22 2016, @11:01PM (#417687) Journal

    At first I thought it was the alcohol that made me lose my balance.

    • (Score: 0) by Anonymous Coward on Sunday October 23 2016, @04:20PM

      by Anonymous Coward on Sunday October 23 2016, @04:20PM (#417879)

      They failed to account for Trump's ego.