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Analysis Suggests Solar System Contains Massive Trans-Neptunian Objects

BarbaraHudson writes NBC News reports that at least two planets larger than Earth likely lurk far beyond Pluto, just waiting to be discovered, a new analysis of the orbits of "extreme trans-Neptunian objects" (ETNOs) suggests. The potential undiscovered worlds would be more massive than Earth and would lie about 200 AU or more from the sun — so far away that they'd be very difficult, if not impossible, to spot with current instruments. "The exact number is uncertain, given that the data that we have is limited, but our calculations suggest that there are at least two planets, and probably more, within the confines of our solar system," lead author Carlos de la Fuente Marcos, of the Complutense University of Madrid, said. (Here's the longer version at Space.com.)

170 comments

  1. Nibiru! by Anonymous Coward · · Score: 0

    Hey guys, it is totally real now!

    But really, it would be neat if there were more planets, especially rocky and super-rocky planets.
    Future space for a hopefully future human race to propel in to sunny orbits.

    1. Re:Nibiru! by Anonymous Coward · · Score: 0

      No, no, it's Nemesis.

    2. Re:Nibiru! by Applehu+Akbar · · Score: 2

      But how does Nibiru get those mind-altering toxins to American air carriers so they can be spread through our pristine skies as chemtrails? At those distances, Paul Craig Roberts would probably still have to invoke a wormhole.

  2. Riiiiight. by tysonedwards · · Score: 2, Informative

    Our ability to discern planetary positions has largely been based on our understanding of orbital dynamics and looking for protuberances in the motions of known, directly observed objects that were naked eye observable. This technique has been used since the 16th century and led to discoveries of all Planets, Planetoids, various Asteroids, Comets, and Plutoids ever since without the need of direct imaging; just some very cool math...

    --
    Thirty four characters live here.
    1. Re: Riiiiight. by Anonymous Coward · · Score: 5, Funny

      are your protuberances a little bit perturbed?

    2. Re: Riiiiight. by Anonymous Coward · · Score: 0

      Much like their Shift Key.

    3. Re:Riiiiight. by K.+S.+Kyosuke · · Score: 1

      Yep, but the most recent line of thought has been that all the previously suspicious things about known outer solar system orbits have already been explained away. At least some serious upper bounds have been put on the masses of the potential objects (and lower bounds on their distances). Whether this work on TNOs will withstand close scrutiny is the question to ask.

      --
      Ezekiel 23:20
    4. Re:Riiiiight. by Anonymous Coward · · Score: 1

      Protuberances? That would mean much like Uranus, they are prolapsed.

    5. Re:Riiiiight. by FrostedWheat · · Score: 1

      Most new discoveries are still done through imaging rather than maths. It's fairly automated these days though.

    6. Re:Riiiiight. by Gravis+Zero · · Score: 2

      Yep, 400 years the math has been right... and we only discovered Neptune 169 years ago. Pluto varies between 29 AU and 49 AU from Sol, depending on where it is in it's 248 year elliptical orbit. These hypothetical planets are at least 200 AU from the Sol and have very slow and large orbits taking between 1800 and 12000 years to complete.

      Our math has worked well for 400 years... but how will it hold up in 400K years?

      --
      Anons need not reply. Questions end with a question mark.
    7. Re: Riiiiight. by Will.Woodhull · · Score: 1

      Seeing these protuberances on slashdot perturbs me a little. But I would be seriously perturbed to see protuberances of astronomical size.

      --
      Will
    8. Re:Riiiiight. by Solandri · · Score: 5, Interesting

      This technique has been used since the 16th century and led to discoveries of all Planets, Planetoids, various Asteroids, Comets, and Plutoids ever since without the need of direct imaging; just some very cool math...

      I don't think orbital dynamics has ever been used to discover an asteroid or comet or trans-Neptunian object. Certainly it's used to confirm their orbits (I've done that myself, freezing my ass off overnight taking a glass photographic plate, then measuring how much a small dot moved night to night). But asteroids have too little mass to to appreciably change the orbits of the larger planets. Ceres (along with a lot of other asteroids in the asteroid belt) in particular was discovered by blind luck by people searching almost at random for another planet between Mars and Jupiter. So to for that matter was Pluto - people were chasing what turned out to be an error in Neptune's calculated mass, and Pluto just happened to be near the spot that error predicted at the time they were looking.

      Comets are discovered by (obsessed) people scanning the sky every night for a fuzzy dot that shouldn't be there. It's actually the same process as for asteroids (except now you have a computer do the observation instead of freezing your ass off like I did), and if the orbital calculations say it's a highly elliptical orbit instead of circular, you have a comet. The gas jets from vaporizing material as they approach the sun (which gives them their "tail) are pointed in random directions, and perturbs their orbit enough to make precise orbital calculations useless. Only general calculations like Halley's Comet returning every 86 years work.

      Orbital calculations work well for (A) objects which are relatively close together since gravity decreases as the inverse square of distance, and (B) have relatively short orbital periods since this means they move faster and thus generate a larger measurable motion against the background stars. Neither of these hold true for trans-Neptunan objects.

      If you subscribe to the theory that the solar system started out as a cloud of matter, and a slightly larger lump somewhere happened to coalesce into the sun by gravity, then it makes sense that the further you go out, the more material there is simply because of geometry. The volume of space (restricted to near the plane of the solar system) goes up as the square of the distance from the sun. While the length of the orbit only goes up proportional to the radius. So there must be more stuff in the outer solar system than in the inner. It's just spread out more.

    9. Re:Riiiiight. by Anonymous Coward · · Score: 0

      Even if Percival Lowell's Planet X (or others) exist it would be so far out that its effect on other worlds would take centuries to accumulate enough data to make a respectable hypothesis. Even the article's authors admit that "the data that we have is limited". Such planets could exist, Pluto itself was once theorized to have been an exo-solar wanderer captured by the suns gravity (I don't know if this is still a current valid theory or not).

      However, have the scientists proposing this even considered that it could just be the collective mass of the Kuiper belt / Oort cloud as a whole that has been influencing the orbits of the outer planets?

    10. Re:Riiiiight. by sysrammer · · Score: 1

      ...and for all the GN's out there, a protuberance is a special case of a perturbation.

      --
      His ignorance covered the whole earth like a blanket, and there was hardly a hole in it anywhere. - Mark Twain
    11. Re:Riiiiight. by rtb61 · · Score: 2

      You left out solar wind https://en.wikipedia.org/wiki/... which from the moment of stellar ignition creates a wave which concentrates the dust cloud promoting coalescence into gravitational masses and those masses create turbulence within that dust cloud promoting the formation of comets. So the inner model is planets cores have formed prior to stellar ignition and upon ignition those cores get their final coat. Planets that do not fit that model are shaped by catastrophic impact of one form or another, a very socially uncomfortable viewpoint.

      --
      Chaos - everything, everywhere, everywhen
    12. Re:Riiiiight. by BarbaraHudson · · Score: 1

      Try the discovery of Pluto, which was predicted from orbital irregularities of Neptune, which as also predicted because of orbital irregularities of Uranus.

      --
      "Transparent" is a shit show that trades on every stereotype going. A man in drag is NOT a transsexual.
    13. Re:Riiiiight. by Anonymous Coward · · Score: 0

      As the post you replied to explicitly stated, the calculations of perturbations to Neptune's orbit were later found to be a mistake, and even when Pluto was found, it was way smaller than the planet they were looking for. Pluto was not found because of careful calculations predicting it, but by luck, unlike Neptune which was found very close to where it was expected to be.

    14. Re: Riiiiight. by vpness · · Score: 1

      Thanks for taking the time to post this. I'm glad your post was modded up. I have a casual, uneducated interest in things in space, and snippets like this are interesting to me. (unlike a lot of /. posts, I'm not being sarcastic)

    15. Re:Riiiiight. by Pulzar · · Score: 2

      Comets are discovered by (obsessed) people scanning the sky every night for a fuzzy dot that shouldn't be there.

      I'm completely ignorant on this topic.. but that sounds like something that computers should be able to do easily, no?

      --
      Never underestimate the bandwidth of a 747 filled with CD-ROMs.
    16. Re: Riiiiight. by jcwayne · · Score: 1

      Doesn't the tail of a comet always point directly away from the sun?

      --
      Failure to follow this advice may result in non-deterministic behavior.
    17. Re: Riiiiight. by Anonymous Coward · · Score: 0

      You mean like in Star Wars Clone Wars when Obi Wan lost a whole solar system and Yoda said "look for gravity's pull" to find it?

    18. Re: Riiiiight. by 605dave · · Score: 1

      Don't have mod points, but that would have just qualified as funny to me...

      --
      Be kind, for everyone you meet is fighting a difficult battle. - Plato
    19. Re:Riiiiight. by BarbaraHudson · · Score: 1

      It's called serendipity. Without the perturbations in Neptune's orbit they wouldn't even have started looking for a "Planet X", so Pluto was indeed found because of perturbations in Neptune's orbit.

      --
      "Transparent" is a shit show that trades on every stereotype going. A man in drag is NOT a transsexual.
    20. Re:Riiiiight. by Anonymous Coward · · Score: 0

      Except there were no perturbations in Neptune's orbit, it was just a mistake in their numbers. And Pluto was not where they predicted the missing planet to be, and was found when they resorted to a brute force search of the sky. No predictive power was involved, it was just luck, and brute force searches were already used for asteroids before and after the discovery.

    21. Re: Riiiiight. by Applehu+Akbar · · Score: 1

      At those distances, comets don't even have tails.

    22. Re: Riiiiight. by Anonymous Coward · · Score: 0

      The ion tail is influenced by the solar wind, so it tends to point directly away from the Sun, but could deviate from that. The dust tail takes longer to be influenced by the solar wind and light, so it tends to carry a lot of momentum from when it comes off the comet and ends up being somewhere between the direction away from the sun and the direction where the comet came from.

    23. Re:Riiiiight. by Anonymous Coward · · Score: 0

      in it's 248 year

      "its".

    24. Re:Riiiiight. by Tablizer · · Score: 1

      I think it's only recent that electronic cameras have been sensitive enough at a price amateur comet hunters could afford. Plus, it probably takes a lot of hard-drive space to store comparative images.

  3. Probe by Anonymous Coward · · Score: 0

    Launch a probe and have it hang out in the calculated orbit and if it hits something, report back?

    1. Re:Probe by beelsebob · · Score: 2

      1) It's very difficult to get there - Voyager 1 and 2 are the only probes ever to get that far from the sun and still be functional, and they took decades to get there
      2) If you hang around in the orbit of the planet, then you'll have the same orbital period as it. Effectively, you'd stay stationary relative to the planet, and as a result never spot it unless you got lucky and landed exactly where the planet was.

    2. Re:Probe by Anonymous Coward · · Score: 1

      Not to mention the orbital speed even if the probes stayed still. IIRC Pluto hasn't circled the Sun once since it was found.

    3. Re:Probe by stjobe · · Score: 3, Informative

      You recall correctly; Pluto hasn't even made it half a lap around the sun since we discovered it.

      It was discovered in 1906, 108 years ago, and it's orbital period is 247.68 years.

      --
      "Total destruction the only solution" - Bob Marley
    4. Re:Probe by Anonymous Coward · · Score: 2, Funny

      You think in another 108 years you'll have mastered the difference between its and it's?

    5. Re:Probe by Anonymous Coward · · Score: 0

      Do you think in another 108 years that you'll have mastered the difference between its and it's?

      FTFY

    6. Re:Probe by Anonymous Coward · · Score: 1

      You recall correctly; Pluto hasn't even made it half a lap around the sun since we discovered it.

      It was discovered in 1906, 108 years ago, and it's orbital period is 247.68 years.

      Incorrect, Pluto was discovered on February 18, 1930 by Clyde W. Tombaugh.

      Percival Lowell started looking for trans neptunian objects in 1906 if you read here:

      http://en.wikipedia.org/wiki/Pluto

      That being said, being a serious Doctor Who fan, I hope that one of these planets the article postulates to exist, when found, is named Cassius so that K-9's statement in the episode "The SunMakers" turns out to be true.

    7. Re:Probe by Anonymous Coward · · Score: 0

      You think in another 108 years you'll have mastered the difference between its and it's?

      Perhaps while he is at learning that both he and slashdot can learn to check facts before posting them and quit modding down people who try to correct them.

      hit load all comments and you will see that I corrected the fact two people incorrectly said that pluto was discovered in 1906, when it was discovered in 1930 and I posted a link where you could verify this .. and it was modded down..

      Slashdot used to be news for nerds, but lately, I am just not impressed anymore.

      1930, Lowell observatory in Flagstaff, Arizona, by Clyde Tombaugh with 2 photographic plates of pictures taken of the sky looking for the thing that moved.. which was Pluto.. (Apparently I have to put it in "Clue terminology" to have it noticed!)

    8. Re:Probe by SharpFang · · Score: 1

      As for 2), if you move in the retrograde orbit, you're bound to encounter the planet twice per its orbital period. Any probes towards the transneptunian objects (except for these with landers) should move in retrograde direction (opposite to how the planets travel), this way they will be able to observe them in reasonable timeframe.

      --
      45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
    9. Re:Probe by AthanasiusKircher · · Score: 1

      You recall correctly; Pluto hasn't even made it half a lap around the sun since we discovered it.

      It was discovered in 1906, 108 years ago

      WTF MODS? This gets "+5 informative"??

      Pluto was discovered in 1930, as anyone could verify anywhere. Jesus Christ. This is NOT an obscure fact, particularly for anyone who knows anything about the solar system. I've been reading Slashdot for a long time, and I've seen a lot of crap, but I'm seriously thinking of leaving now. News for "nerds" my ass.

    10. Re:Probe by beelsebob · · Score: 1

      Where by "reasonable timeframe" you mean "once every 2 and a half millennia", plus, getting into a retrograde orbit around the sun increases the fuel bill, and the issue with point 1) even more.

    11. Re:Probe by Anonymous Coward · · Score: 0

      I don't know where the parent got 1906 unless they misremembered 1909. We have photographic plates of Pluto going back to 1909, it just wasn't recognized to be Pluto until 1930.

    12. Re:Probe by SharpFang · · Score: 1

      Getting into the retrograde orbit necessitates a close Jupiter flyby in order to reverse direction.

      two and half millennia per probe per object per flyby (as opposed to observation from a long distance). Nevertheless that's already vastly better than 'never'.

      --
      45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
  4. The correct answer by Anonymous Coward · · Score: 0

    is 6. There are 6 planets orbiting Sol that humanity hasn't discovered. Honestly, we're kind of surprised you guys haven't blown each other up yet, what with your complete inability to leave your own gravity well even. That's considered child's play to the rest of the universe.

    1. Re:The correct answer by gatkinso · · Score: 1

      Says the grown up tape worm to the baby human.

      --
      I am very small, utmostly microscopic.
  5. Yuggoth by chill · · Score: 0, Troll

    Beware! This heralds the return of the Great Old Ones! (Just in time for the U.S. 2016 election season it seems.)

    Keep an eye out for Mi-Go.

    --
    Learning HOW to think is more important than learning WHAT to think.
    1. Re:Yuggoth by stjobe · · Score: 4, Funny

      "Why choose the lesser of two evils? Vote Cthulhu for President 2016"

      --
      "Total destruction the only solution" - Bob Marley
    2. Re: Yuggoth by Anonymous Coward · · Score: 0

      He's not a flip-flop politician. You know where you stand... Sacrifices now or sacrifices later.

    3. Re: Yuggoth by Anonymous Coward · · Score: 0

      Flip-flop politician = A politician who is open and willing to change their stance based on new information, like any rational human being would.

  6. Planet X / Nibiru !!! by Anonymous Coward · · Score: 1

    Seriously though, if such a planet did exist and the had an orbit that brought it near our planet once every so many thousnads of years, what effect would it have as it passed near us? Look at the effect the moon has on our planet and think about something larger than Earth passing by.

    1. Re:Planet X / Nibiru !!! by Urkki · · Score: 3, Informative

      I think Jupiter makes sure any highly elliptical orbit coming near Jupiter's orbit would not last too many orbits before having it's orbit radically changed, like happens with comets sooner or later if they survive long enough otherwise.

    2. Re:Planet X / Nibiru !!! by Teun · · Score: 1

      If such existed it would have passed us before and left obvious traces.

      --
      "The likes of Facebook and WhatsApp are free to those whose privacy is of zero value."
    3. Re:Planet X / Nibiru !!! by Anonymous Coward · · Score: 0

      Look at the effect the moon has on our planet and think about something larger than Earth passing by.

      But that is because it is so close. The force scales with mass, but inversely with distance squared. The passing planet could be the same mass as Earth, but would have to pass within 10 times the distance of the Moon's orbit to have the same effect.

    4. Re:Planet X / Nibiru !!! by ArcadeMan · · Score: 1

      The obvious traces are everywhere, we just choose to ignore them and think they were man-made.

    5. Re:Planet X / Nibiru !!! by dbreeze · · Score: 1

      Like the records of some ancient civilizations maybe....?

      --
      When the king heard the words of the Book of the Law he tore his robes.2Kings22:11
    6. Re:Planet X / Nibiru !!! by JWSmythe · · Score: 4, Interesting

      Everywhere is relative. There are an estimated 5 trillion habitable planets in the known universe. We've mostly explored one. On our closest neighbors, we've done roughly the equivalent of checking your back yard and saying "There are no whales". Well, unless you happen to have whales in your yard, then we'll say "... no elephants". :)

      If there is/was life on other planets, it is very likely not to be in our solar system. Even if there was an species that achieved space travel, and spent millions of years settling on millions of planets, it's *still* not very likely they'd be found on one in our solar system.

      Even if we found one, would we know what we're looking at? Since rock seems to be pretty abundant in the tiny speck of space that we've explored, a sand and rock covered hull of a spacecraft would be reasonable. That would help protect from micro-meteors and other hazards. If one crashed on a neighboring planet even 10,000 years ago, would just look like rock. Heck, if one crashed on Earth, it would still look like a rock.

      Is this space craft remains, or a natural formation?

      No, I don't believe it's a crashed spaceship. It's just a rock. But since we don't exactly do thorough core samples on every large rock on the planet (and under the surface), we wouldn't know if it was.

      --
      Serious? Seriousness is well above my pay grade.
    7. Re:Planet X / Nibiru !!! by ArcadeMan · · Score: 1

      This looks like a photo of the rough pass of a CNC milling operation that has gone through a very bad resizing routine, probably nearest-neighbor interpolation.

    8. Re:Planet X / Nibiru !!! by Anonymous Coward · · Score: 0

      The way I see it is by the time a race reaches the level of star travel, their knowledge would be vast and their technology would seem like magic. Finding Earth out of all of the other planets in the universe would be like looking for one specific grain of sand somewhere here on Earth and that's if they are even interested in us or had something to learn about us, which they probably wouldn't. If they did, they'd just send nanoscale robots to survey and we'd never even know it. Think about this, how often do you stop to random inspect the ground for microbes? Well in this case, the microbes are us.

      The rest of the beings out there will either be below or roughly at our same level of development, which means they absolutely cannot travel the stars, nor will they be able to for a very long time.

    9. Re:Planet X / Nibiru !!! by Anonymous Coward · · Score: 0

      The effect would be climate warming..

    10. Re:Planet X / Nibiru !!! by plopez · · Score: 3, Interesting

      "We've mostly explored one"

      Not even close to 'mostly'. The land areas often have areas very little understood, we can't find a crashed airliner in the ocean, we know very little of the crust though some discoveries of extremophiles underground hint at some weird biology and chemistry, and can't even get sol microbes into the lab without killling them. Before we try to understand other planets it might be a good idea to understand Earth first.

      --
      putting the 'B' in LGBTQ+
    11. Re:Planet X / Nibiru !!! by Anonymous Coward · · Score: 0

      That's a butte, you idiot, and we know perfectly well how they form. We don't need core samples to decide whether it is a spacecraft or not.

    12. Re:Planet X / Nibiru !!! by JWSmythe · · Score: 1

      Dude, it's from Close Encounters of the Third Kind. I picked it on purpose, just to show that I wasn't totally serious. Damn, you'd think an obvious landmark from an extremely popular science fiction movie would be a hint to some people.

      I'm not saying that it's an alien spacecraft. What I'm saying is, we wouldn't necessarily know if we saw one. Hell, people find all kinds of "lost" things in their own back yards. In the last year, someone found a viking burial site. Someone else literally found buried gold. Would you know if there was an ancient spacecraft buried 20 feet under your house?

      I wasn't even trying to propose that alien spacecraft do have rock shielding. What I'm saying is there's a lot we *don't* know. Short of seeing a spacecraft that looks like a spacecraft as we'd expect it, we could easily overlook it.

      --
      Serious? Seriousness is well above my pay grade.
    13. Re:Planet X / Nibiru !!! by JWSmythe · · Score: 1

      We've explored more of this rock than any other. That's the "mostly".

      Finding the lost airliner isn't a matter of lack of exploration. That is, we can't recheck an entire ocean in a short period to see if the airliner is there now. I believe that part of the ocean was already mapped, so it has already been "explored".

      Your airplane argument would be like saying you haven't explored your back yard, if someone tossed a beer can over the fence yesterday, and you didn't know about it.

      BTW, I tossed a beer can over your fence yesterday, you should go clean it up, your yard is a mess.

      --
      Serious? Seriousness is well above my pay grade.
    14. Re:Planet X / Nibiru !!! by Anonymous Coward · · Score: 0

      Everywhere is relative. There are an estimated 5 trillion habitable planets in the known universe. We've mostly explored one. On our closest neighbors, we've done roughly the equivalent of checking your back yard and saying "There are no whales". Well, unless you happen to have whales in your yard, then we'll say "... no elephants". :)

      If there is/was life on other planets, it is very likely not to be in our solar system. Even if there was an species that achieved space travel, and spent millions of years settling on millions of planets, it's *still* not very likely they'd be found on one in our solar system.

      Even if we found one, would we know what we're looking at? Since rock seems to be pretty abundant in the tiny speck of space that we've explored, a sand and rock covered hull of a spacecraft would be reasonable. That would help protect from micro-meteors and other hazards. If one crashed on a neighboring planet even 10,000 years ago, would just look like rock. Heck, if one crashed on Earth, it would still look like a rock.

      Is this space craft remains, or a natural formation?

      No, I don't believe it's a crashed spaceship. It's just a rock. But since we don't exactly do thorough core samples on every large rock on the planet (and under the surface), we wouldn't know if it was.

      It is just "Adam's Ark"

      http://www.galactica.tv/main/what-is-battlestar-galactica.html

      pay it no mind, it has been there forever and a day..

    15. Re:Planet X / Nibiru !!! by Applehu+Akbar · · Score: 1

      Devils Tower is a volcanic stump, not a butte. A butte forms in sedimentary strata as one of the final steps in the erosion of a dissected plain (cut up by rivers, which deepen into canyons...). When there are softer layers of rock underlying hard layers, they undercut during erosion, forming a 'mesa' with more or less vertical sides. When a mesa becomes thinner than it is tall, it gets classified as a butte.

      A volcanic stump forms when a volcano comes up through country rock (no, that has nothing to do with Trisha Yearwood) that is softer than the magma basalt. With enough erosion, the basalt stands alone, cracking into those characteristic hexagonal columns.

    16. Re:Planet X / Nibiru !!! by ArcadeMan · · Score: 2

      Would you know if there was an ancient spacecraft buried 20 feet under your house?

      It would certainly explain why my appliances work without being connected.

  7. I still think Pluto is a planet by HangingChad · · Score: 4, Informative

    I think Pluto got robbed.

    --
    That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage
    1. Re:I still think Pluto is a planet by modmans2ndcoming · · Score: 1

      It has not cleared it's orbit of debris and Eris is in the same boat yet LARGER than Pluto.... how is Pluto a planet then?

    2. Re:I still think Pluto is a planet by Anonymous Coward · · Score: 2, Funny

      Pluto has tenure.

    3. Re:I still think Pluto is a planet by Anonymous Coward · · Score: 0

      Bullshit criterion. Neptune hasn't cleared its orbit of debris because Pluto crosses its orbit. Is Neptune a planet?

    4. Re:I still think Pluto is a planet by michelcolman · · Score: 1

      I wonder what they're going to call these new objects, because they'll probably find a reason not to call them planets just like they did for Pluto.

      They're too big to be dwarf planets... Maybe elf planets?

    5. Re:I still think Pluto is a planet by jc42 · · Score: 2

      It has not cleared it's orbit of debris and Eris is in the same boat yet LARGER than Pluto.... how is Pluto a planet then?

      Neither has Earth; there's a rather large, bright rock visible in our sky about half the time. ;-)

      Seriously, though, it's probably just a matter of time before a rock bigger than Earth is discovered out in the Kuiper belt and/or the Oort Cloud, and chances are pretty slim that its orbit will be "cleared" of rubble. This will either put an end to the current (somewhat bogus) definition of "planet", or it will cause the debate over what's a planet and what's not to bumble on indefinitely.

      The most likely result will be that astronomers will eventually reject the term "planet" entirely. Sorta like how, a few centuries back, they rejected the older term "astrology", due to all its baggage and mis-use by pseudo-scientists and charlatans.

      In any case, the big rocks in the sky don't really care how we classify them. They just go about their orbiting, occasionally bashing into each other (and occasionally us) at widely-spaced intervals.

      --
      Those who do study history are doomed to stand helplessly by while everyone else repeats it.
    6. Re: I still think Pluto is a planet by ilguido · · Score: 2

      Troll planets would be nice.

    7. Re:I still think Pluto is a planet by Anonymous Coward · · Score: 0

      I wonder what they're going to call these new objects, because they'll probably find a reason not to call them planets just like they did for Pluto.

      They're too big to be dwarf planets... Maybe elf planets?

      They'll probably be called KP's. Kuiper Planets..

    8. Re:I still think Pluto is a planet by Anonymous Coward · · Score: 0

      Pluto is not debris.

    9. Re: I still think Pluto is a planet by jd2112 · · Score: 1

      Troll planets would be nice.

      No thanks, we have enough lurking on the Internet. We don't need whole planets of them.

      --
      Any insufficiently advanced magic is indistinguishable from technology.
    10. Re:I still think Pluto is a planet by K.+S.+Kyosuke · · Score: 3, Interesting

      Actually, Neptune has forced Pluto into a 2:3 orbital resonance, thus Neptune has effectively cleared its orbit of Pluto: Pluto never approaches Neptune more than it aproaches Uranus.

      --
      Ezekiel 23:20
    11. Re: I still think Pluto is a planet by DeBaas · · Score: 1

      Indeed if Elon Musk connects a planet full of them to our internet, we're really fscked .....

      --
      ---
    12. Re:I still think Pluto is a planet by Anonymous Coward · · Score: 0

      Preventing close approaches is not the same as clearing an orbit.

    13. Re:I still think Pluto is a planet by K.+S.+Kyosuke · · Score: 1

      It means that Pluto is gravitationally dominated by Neptune. For the purpose of the definition of "clearing the neighborhood", this is perfectly sufficient, certainly no less then accretion or ejection.

      Plus, after all, orbits are not those fancy circles and ellipses; that's only five out of six orbital elements.

      --
      Ezekiel 23:20
    14. Re:I still think Pluto is a planet by Anonymous Coward · · Score: 0

      Your definitions are hard to follow. If Pluto had the mass of Neptune in the same 2:3 orbital resonance orbit, would they both be planets, or neither?

    15. Re:I still think Pluto is a planet by Anonymous Coward · · Score: 2, Interesting

      Why do you say that? I think we can all agree Jupiter is a planet, but due to its size it has an entire category of asteroids (Trojans) which sit at its Lagrange points. Seems to me if the only things in your orbit are there in such a way as to never affect you, and you're that much bigger than them, that's cleared.

    16. Re:I still think Pluto is a planet by Will.Woodhull · · Score: 1

      The most likely result will be that astronomers will eventually reject the term "planet" entirely. Sorta like how, a few centuries back, they rejected the older term "astrology", due to all its baggage and mis-use by pseudo-scientists and charlatans.

      You realize that you are implying that the astronomers who voted in the current astronomical definition of planet are all either psuedo-scientists or charlatans?

      That raises some very serious thought-provoking questions. IMHO, using only common sense and no optical assistance mechanisms, it looks to me like they are probably pseudo-scientists, and not charlatans.

      --
      Will
    17. Re:I still think Pluto is a planet by Will.Woodhull · · Score: 1

      They will be known as "midget planets", I would think.

      Except for the ones that are larger than Earth. Those will be taxonomy busters.

      --
      Will
    18. Re:I still think Pluto is a planet by Anonymous Coward · · Score: 0

      It has not cleared it's orbit of debris

      So now you're wanting to confer planetary status based on its housekeeping ?? All the planets struggling to get by and not rich enough to hire orbital maid service get demoted, and the rich ones promoted. I'm surprised to be reading such elitist crap here.

    19. Re:I still think Pluto is a planet by Anonymous Coward · · Score: 0

      Preventing close approaches is not the same as clearing an orbit.

      It is, if you ignore all of the pop-sci garbage that acts like "clearing an orbit" is completely meaningless, and instead look at what astronomers actually talked about, including that forcing other bodies into resonance was part of what counted as clearing an orbit.

      Or just ignore the resonance completely, and see that the amount of stuff crossing Neptune's orbit is less than 0.01% of its mass, while the stuff crossing Pluto's orbit (ignoring Neptune and its moons) has nearly 500 times the mass of Pluto. There is far more mass in Neptune than anything else in its orbit, while there is far more other stuff in Pluto's orbit than in Pluto+Charon, by orders of magnitude.

    20. Re:I still think Pluto is a planet by Anonymous Coward · · Score: 0

      And if it turned out that hydrogen and helium both had a single proton, would we still call them separate elements? That question is irrelevant because the definitions of chemistry were built around the way the world is and not some hypothetical with radically different principles.

      Similarly, the current definition of planet was explicilty designed to handle our solar system as is, and to be updated later when a better understanding of other planetary systems allows for having some idea of what is out. For now, there is a massive amount of literature dealing with our own solar system that could use some clarification/standardization of terms. If down the line it turns out a different definition facilitates communication better, than it can be changed. Because it is not like the definition is set in stone or dictates how the universe works, it is just there to simplify communication in science literature.

    21. Re:I still think Pluto is a planet by jouassou · · Score: 1

      There are mathematically precise ways of defining the difference between planets and dwarf planets. If you check the table of planetary discriminants a little bit down the page, you see that there clearly appears to be two groups of planetoids in the list: those with a planetary discriminant of 10,000-1,000,000 which we call planets, and those with a planetary discriminant of 0.01-1.00 which we now call dwarf planets. Do you still disagree that these two groups, separated by four orders of magnitude in their planetary discriminants, deserve different names?

    22. Re:I still think Pluto is a planet by Anonymous Coward · · Score: 1

      Uh no. Just no. Pluto's orbit does not ever directly intersect Neptune's orbit. It doesn't even sit on the same plane.

      Go read some books or something.

    23. Re:I still think Pluto is a planet by Anonymous Coward · · Score: 0

      Why is Mercury seen classified as a planet as well? It's a barren rock which is what Pluto is as well... they both should be classified as a moon than anything else.

    24. Re:I still think Pluto is a planet by jc42 · · Score: 1

      The most likely result will be that astronomers will eventually reject the term "planet" entirely. Sorta like how, a few centuries back, they rejected the older term "astrology", due to all its baggage and mis-use by pseudo-scientists and charlatans.

      You realize that you are implying that the astronomers who voted in the current astronomical definition of planet are all either psuedo-scientists or charlatans?

      That raises some very serious thought-provoking questions. IMHO, using only common sense and no optical assistance mechanisms, it looks to me like they are probably pseudo-scientists, and not charlatans.

      Well, they apparently spent some time in meetings of an international organization discussing the definition of "planet", when they could have been doing actual scientific work. ;-)

      Of course, sometimes terminology is important scientifically, and it's worthwhile spending time to get it right. But they were mocked by other actual astronomers pointing out that any term that includes both Mercury and Jupiter but not some objects with intermediate properties must be an absolutely worthless term for any scientific purposes. So, at least during the time they spent in such discussions of the definition of "planet", they weren't functioning as scientists. But they were pretending that the terminology involved had scientific value, so it probably did qualify for the term "pseudo-science", in at least one of its common meanings.

      --
      Those who do study history are doomed to stand helplessly by while everyone else repeats it.
    25. Re:I still think Pluto is a planet by cheesybagel · · Score: 1

      Nah those will be the "mighty midget" planets.

    26. Re:I still think Pluto is a planet by Anonymous Coward · · Score: 0

      "It means that Pluto is gravitationally dominated by Neptune."
      50 Shades of Uranus?

    27. Re:I still think Pluto is a planet by dissy · · Score: 1

      Until you can name all hundred thousand of the "planets" in our solar system, we won't be using your definition of planet.

      Why do you insist 3rd graders should be able to recite all hundred thousand planets from memory yet refuse to do so yourself even with the Internet as your reference?

    28. Re:I still think Pluto is a planet by Anonymous Coward · · Score: 0

      The word root for planet meant "wanderer" and was from the days when people thought they were wandering stars. So sure, all of those bits of flotsam wander and are then, in effect, planets. If we want to call them size challenged wanderers or dwarf wanderers - sure, we can be discriminatory as you suggest. Discrimination isn't illegal against planets at this time.

    29. Re: I still think Pluto is a planet by Applehu+Akbar · · Score: 1

      "Troll planets would be nice."

      And because of the latency, the inhabitants would be enable to form coherent ripostes to our posts.

    30. Re:I still think Pluto is a planet by C0R1D4N · · Score: 1

      Is Australia a continent or a very large island?

    31. Re:I still think Pluto is a planet by Anonymous Coward · · Score: 0

      In what geographic contexts would that make a difference beyond the size of lists some kids have to memorize for school? Would anything change if flipped it from one to other, other than Greenland losing the title "largest island"?

      Even in geology, where there are more specific definitions of associating continents with cratons, which Australia has, defining it as a large island just means a lot of papers will need to say "the continents and Australia." But even there it doesn't make much difference, as more often than not someone would be talking about the plates and the Australian plate is more well defined. And geologist were quite capable of coming up with the idea of "continental fragments" when needing to describe a more general class of things with continental crust but no cratons.

    32. Re:I still think Pluto is a planet by Anonymous Coward · · Score: 0

      Just like how none of these posts are made by anonymous people, because that comes from words meaning "without name" and we all have names even if they are not attached to the post. And ACs, and no human for that matter, are cowards, because it is derived from the word for "tail" which virtually no humans have past birth.

    33. Re:I still think Pluto is a planet by david_thornley · · Score: 1

      Given the proximity of New Guinea, it's safe to say it isn't a planet.

      --
      "When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
    34. Re:I still think Pluto is a planet by Anonymous Coward · · Score: 0

      cleared it's orbit

      "its".

    35. Re:I still think Pluto is a planet by ghurlag · · Score: 1

      Pretty sure this sums up this whole argument nicely. It's like the Kevin Bacon game, only with planetary and geographical bodies. Where x=( and purple is the new feather.

  8. In Soviet Russia by Anonymous Coward · · Score: 0

    Analysis PROVES that Trans-Siberian Railroads You!

  9. Planets? by Sperbels · · Score: 3, Insightful

    At that range, you have to wonder enough time has elapsed since the formation of the solar system for them to have "cleared the neighborhood" around their orbits.

    1. Re:Planets? by CanEHdian · · Score: 2

      Plenty if you assume the orbital period to be around 5,000 years (see e.g. 2012_VP113)

      --
      When the copyright term is "forever minus a day", live every day like it's the last.
    2. Re:Planets? by Urkki · · Score: 1

      At that range, you have to wonder enough time has elapsed since the formation of the solar system for them to have "cleared the neighborhood" around their orbits.

      If they are detected by looking at how they herd the minor bodies in the outer solar system, then I think it is safe to say they are indeed planets.

    3. Re:Planets? by war4peace · · Score: 1

      Interesting point. Let's say a planet orbits the Sun once every 1000 years (Pluto's is almost 248 years). This means roughly 4.6 million planetary "years" from that planet's reference frame. Did Earth clear its orbital neighborhood in 4.6 million years? Probably not.

      --
      ...gis sdrawkcab (usually not responding to ACs; don't bother posting as AC)
    4. Re:Planets? by Anonymous Coward · · Score: 0

      Considering the evidence that suggests these objects existence is the disturbance of the orbits of Kuiper belt objects, you already know the answer is that they have not "cleared the neighborhood", and as such do not meet the definition of planet. When found, they will have to be classified as Kuiper belt objects like Pluto, or maybe, with enough mass or other different characteristics be classified as a different type of object - a hyper-Kuiper belt object perhaps?

    5. Re:Planets? by K.+S.+Kyosuke · · Score: 2

      This is actually a valid question for the transneptunian space. I vaguely recall that between the times and spaces involved, the transneptunian space may not have "aged" to the same extent that the inner parts of the Solar System have. There simply has to be a threshold somewhere where the definition stops making sense, so it's only applicable to those places where something like this is possible.

      --
      Ezekiel 23:20
    6. Re:Planets? by Anonymous Coward · · Score: 0

      Dwarf planet is fine according to wikipedia:
      is in direct orbit of the Sun[1]
      is massive enough for its gravity to turn it into a nearly round shape
      has not cleared the neighborhood around its orbit.[2]
      http://en.wikipedia.org/wiki/Dwarf_planet

    7. Re:Planets? by SharpFang · · Score: 1

      I don't exactly know what the "neighborhood" is defined as, but note how its volume (and as result, space that is to be cleared) rises with cube of orbital radius. At 200AU the hypothetical planets have 8,000,000 times more cubic kilometers of space to wipe than Earth does.

      --
      45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
    8. Re:Planets? by Anonymous Coward · · Score: 1

      Quantitative work has been done on how difficult it is to scatter crossing orbits and for other smaller bodies into a resonance, and the difficulty doesn't quite scale with volume, but scales with orbit diameter (or semi-major axis for elliptical orbits) to the (3/2) power, while also scaling with the square of the bodies's mass. So in that sense, moving Earth out to a distance of 200 AU would make it roughly 3000 times harder to scatter bodies out of the orbit. But by those estimates, Earth has almost 400 times the necessary mass for the rough threshold in its own orbit, so it would still be plenty to clear out an orbit at 200 AU. However if you look at something like Pluto, its distance and mass give it nearly 10^8 times worse scattering ability, putting it orders of magnitude under the threshold of where a planet would be expected to clear the neighbourhood.

  10. Exciting stuff by benjfowler · · Score: 2

    I hope I'm alive long enough for somebody to build probes that are fast and powerful enough to reach and map these places.

    The trouble with present technology, is that most rockets/spacecraft only have enough delta-V to take decades to get out there, and nowhere near enough to actually go into orbit when they get out there.

    Hazarding a guess, I would say that that'll only happen when somebody gets around to building nuclear-powered engines. The big question is: who's got the money and balls to pull it off?

    1. Re:Exciting stuff by Anonymous Coward · · Score: 0

      Whoa whoa big boy!

      Before you can send any probes to any such place, the first thing you need to do is find the darn things. And here you are, sending probes to things that haven't been found.

    2. Re:Exciting stuff by 7bit · · Score: 2

      Whoa whoa big boy!

      Before you can send any probes to any such place, the first thing you need to do is find the darn things. And here you are, sending probes to things that haven't been found.

      Well humans, at least 49% of us, are all about the probing. Tell us about something we haven't probed before and we'll start working out plans right away for how we WILL probe it. Kinda makes me think those Grey aliens that are busy probing farmers really are us from the future...

    3. Re:Exciting stuff by 7bit · · Score: 1

      Whoa whoa big boy!

      Before you can send any probes to any such place, the first thing you need to do is find the darn things. And here you are, sending probes to things that haven't been found.

      Well humans, at least 49% of us, are all about the probing. Tell us about something we haven't probed before and we'll start working out plans right away for how we WILL probe it. Kinda makes me think those Grey aliens that are busy probing farmers really are us from the future...

      Dammit! Must. Remember. To. Click. Anonymous...

    4. Re:Exciting stuff by SharpFang · · Score: 1

      It's nowhere near impossible, it would just require a decent budget.

      First, not a single probe but a bunch of them, to cover more of the space. Of course not all at once, but a program of sending a new one every five years or so would be nice.
      Next, equip the probes with decent telescopes. Something like Hubble, maybe a little more on the budget side. The number of probes and the time would contribute to more coverage.
      And give them some surplus fuel. So that if something is discovered, a probe can be redirected for a closer fly-by.

      --
      45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
    5. Re:Exciting stuff by Anonymous Coward · · Score: 0

      Something like Hubble, maybe a little more on the budget side.

      Hubble is pretty bad for discovering small bodies at a distance. TNOs tend to be discovered by wide angle scopes with a lot of data processing doing automatic surveys. Hubble is great seeing dim objects by taking very long exposures, sometimes longer than possibly with ground based scope, but that requires you already know where to look.

      And give them some surplus fuel. So that if something is discovered, a probe can be redirected for a closer fly-by.

      In order to get the delta-v needed to significantly change where they can go on a fly by at a distance of ~200 AU, say a couple AU, while not taking 50 years to get to that distance, would mean you would need a craft that is about 95% fuel assuming a high specific impulse engine like an ion engine. Something similar in size to the HST would need fuel on the order of half the ISS launched into deep space (so, if still using ion engines, would require fuel on the order of the whole mass of ISS placed in orbit, assuming no fuel is needed once it left Earth to get a whole lot of gravitational boosts to get into the outer solar system).

      If you went with a probe something the size of New Horizons, which is 20 times less mass than HST, you would at least end up with a gross mass closer to HST instead of the ISS. Although now you might be limited to searching for things within 10-30 AU, which means it would take ~40 some craft to cover a 200 AU orbit, assuming it is not inclined too much.

      Of course it is not impossible, but how people would interpret "decent budget" might be kind of distant from a program of that magnitude.

    6. Re:Exciting stuff by SharpFang · · Score: 1

      If you introduce the change early enough, even little fuel can change the direction a lot. Note there's a bunch of probes so one can always pick one with trajectory pretty close to optimal, and adjust it early enough. The timeframe would certainly be decades too - I'm thinking of something like Voyager 1, except with a lot of modern technology. New Horizons is one of the newer generation, "budget" probes. Small, lightweight and slow. These would still need budget of the class of Cold War era...

      --
      45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
  11. Nothing new by Anonymous Coward · · Score: 1, Insightful

    Alf already predicted this http://alf.wikia.com/wiki/Alvin

  12. Of course! by __aaclcg7560 · · Score: 2, Interesting

    This would explain why SPACE: 1999 had the runaway Moon passing a planet outside the solar system in every episode. For all these years, I thought British SF TV was just weak in the science department.

    1. Re:Of course! by Anonymous Coward · · Score: 0

      This would explain why SPACE: 1999 had the runaway Moon passing a planet outside the solar system in every episode.

      From a remarkably similar wakkipedia page on Space 1999 itself, not Maya..

      '...Not long after leaving Earth's solar system, the wandering Moon passes through a black hole and later through a couple of "space warps" ..'

      For all these years, I thought British SF TV was just weak in the science department.

      Well yes, it was weak in the science department, I think that was something to do with the fiction thingie...

    2. Re:Of course! by gronofer · · Score: 1

      If I remember correctly, they did have a scientific explanation for that. The explosion that separated the Moon from the Earth was so powerful that its relative velocity was close to the speed of light, so distance was contracted according to the theory of relativity.

      However, I don't remember any explanation for how the moon and its inhabitants could survive intact with such a powerful explosion and rapid acceleration. Maybe I need to go and rewatch the series to find out.

  13. More probing needed? by Tablizer · · Score: 0

    You mean there is something up Uranus?

  14. Kraftwek was right... by Anonymous Coward · · Score: 0

    Trans Neptunian Express!

  15. Fastest Probe? [Re:Exciting stuff] by Tablizer · · Score: 1

    I wonder what the fastest possible chemically-propelled-rocket probe is? If the probe was made small and compact to do little more than take photos and spectrographic analysis, how fast could the bugger be made to travel using existing rocket tech?

    If it records the pass-by data and sends it back later at a slower pace, somewhat like New Horizons, then it doesn't need that big of an antenna.

    1. Re:Fastest Probe? [Re:Exciting stuff] by stjobe · · Score: 4, Interesting

      I wonder what the fastest possible chemically-propelled-rocket probe is? If the probe was made small and compact to do little more than take photos and spectrographic analysis, how fast could the bugger be made to travel using existing rocket tech?

      While not chemically-propelled, Freeman Dyson calculated while working on the Orion project that one of those magnificent bastards could achieve 3.3% of the speed of light (0.03c, 10,000 km/s, or roughly 22 million kph - give or take a few hundred thousand mph - by firing a shaped-charge nuclear bomb behind it every three seconds for ten days straight.

      At that speed, Alpha Centauri is just 133 years away, and these ETNOs are really not much farther than down the road to the chemist.

      It's a shame that project never came to anything but a few chemical proof-of-concept scale tests.

      --
      "Total destruction the only solution" - Bob Marley
    2. Re:Fastest Probe? [Re:Exciting stuff] by Tablizer · · Score: 1

      by firing a shaped-charge nuclear bomb behind it every three seconds for ten days straight.

      That's a lot of nukes.

    3. Re:Fastest Probe? [Re:Exciting stuff] by DanielRavenNest · · Score: 2

      > I wonder what the fastest possible chemically-propelled-rocket probe is?

      Slower than a Nuclear-ion probe. Nuclear in this case means a small nuclear reactor, say in the 1 MW power range. Plasma thrusters have an exhaust velocity of ~ 50 km/s, and it is reasonable to reach 3x exhaust velocity, thus 150 km/s. The mass ratio (propellant to empty mass) would be 20:1 in that case. For any kind of chemical rocket to reach that velocity, it would need a mass ratio of 10 trillion, which is seriously impractical.

      150 km/s = 31.6 AU/year, therefore missions to around 300 AU would be reasonable (10 year trip time). 1 MW reactor with radiators would mass ~ 20 tons. 300 AU probe would mass ~ 5 tons. Propellant load would be 25x20 = 500 tons. Propellant flow rate is .57 grams/sec or 49 kg/day. So thrust time is 28 years, which is a bit long. It would help if the reactor could be made lighter.

    4. Re:Fastest Probe? [Re:Exciting stuff] by stjobe · · Score: 1

      Yep. 300,000 1-megaton yield nukes at 1 metric ton each.

      The proposed design had a departure mass of 400,000 tons, with a 50,000 ton payload.

      --
      "Total destruction the only solution" - Bob Marley
    5. Re:Fastest Probe? [Re:Exciting stuff] by Tablizer · · Score: 1

      Nukes carry a lot of politics with them even if price was no object.

      What about a solar sail that also uses the big planets as a gravity sling-shot?

  16. Protoplanetary clouds never disappear? by Anonymous Coward · · Score: 0

    Ok so, protoplanetary clouds and discs are much larger than the solar system forming inside them? The solar system slowly erodes ever larger cavity inside the center of the cloud, never destroying it completely... We are still inside our protoplanetry cloud.

  17. New System: Kuiper Planets by 7bit · · Score: 5, Interesting

    I wonder what they're going to call these new objects, because they'll probably find a reason not to call them planets just like they did for Pluto.

    They're too big to be dwarf planets... Maybe elf planets?

    Perhaps KP's, Kuiper Planets. Which could start a whole new Planetary naming system based on regional distance from a star instead of what we have now. Everything round + blah between the Star and it's local Kuiper Belt type region would be either an Inner Planet or Solar Planet, everything otherwise fitting that definition but within the Kuiper Belt would be a Kuiper Planet and anything further than that would be an Oort Planet.

    That might even allow Pluto to be reclassified as a planet again, either a Solar Planet or Kuiper Planet. I really think this system, plus other basic details like roundness etc, could be a more useful system. It would also allow a way to keep the number of planets more manageable since we could mostly focus on the Inner/Solar Planet count for general public use without the number of them being too high to manage.

    New Planet types based on Region/Distance from star:

    Inner Planet or Solar Planet
    Kuiper Planet
    Oort Planet

    btw: I made a post as anon under the same parent post before this, then thought I should log in and elaborate. The previous post was:

    " They'll probably be called KP's. Kuiper Planets."

    1. Re:New System: Kuiper Planets by SuperKendall · · Score: 1

      That seems like a really good idea, sorry I have no mode points to promote.

      --
      "There is more worth loving than we have strength to love." - Brian Jay Stanley
    2. Re:New System: Kuiper Planets by Tablizer · · Score: 2

      Mort calling Oort. Mort calling Oort. Manu Manu!

    3. Re:New System: Kuiper Planets by RockDoctor · · Score: 1
      There is a general dispute in taxonomy between "lumpers" and splitters" - people who say "this, this and this share these characteristics, and so I lump them together in one taxon" versus those who say "this, this and this differ in these characteristics, and so I split them into these taxa".

      You're evidently a splitter. No disrespect about that - it's a defensible position (see above). But being a lumper is also a defensible position (see above).

      The important things that you need for designing a taxonomy are to know what questions you want your taxonomy to address - if you're wanting answers to questions of surface gravity, then a taxonomy based on colour is unlikely to be helpful, for example.

      Our current taxonomy for planets is based on the observational status of the planets in respect of their neighbours - the "cleared orbital region" criterion. In principle, that is an addressable question - observe the skies, plot the orbiting bodies down to a few percent of the size of the planets of interest, question answered.

      Where things are getting confused is that many people project questions of the origin of the planets onto the orbital classification. Which may not be the most logical thing to do, when looked at in the context above. The two questions are not strictly related : Earth, Venus, Uranus and Pluto all appear to have suffered a giant impact in the late stage of their construction, but Pluto does not currently have a cleared orbit to make it a "planet" under the orbital classification. So our believed-to-be-correct models of origin processes do not (necessarily) align with current orbital status. But you can see from the length of my qualifications above that one taxonomy split is based on fairly long chains of cause and implication, and the other on simple Newtonian mechanics. So I can understand why the IAU decided to go with the relatively simple present-day orbital status criterion.

      If I were to design a planet taxonomy, I'd use a criterion of sphericity (is the shape within X% of being a simple spheroid) to divide planets from "minor planets" (you can look at it as the interplay of material strength versus object mass, if you like), and at the upper boundary the presence of fusion (separating planets from stars, with a fudge area to deal with brown dwarfs). But that criterion shows my interest in body materials (I'm a geologist by trade), which differs from the interests of astronomers in general.

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
    4. Re:New System: Kuiper Planets by Anonymous Coward · · Score: 0

      between the Star and it's local Kuiper Belt type region

      "its".

  18. Nuclear engines exist by xtal · · Score: 1

    And are well understood.

    Short on balls to use them, though.

    --
    ..don't panic
  19. Rediscovering the 1950s by dorpus · · Score: 1

    They said back then that there is a massive "Planet X" that may orbit in the reverse direction from other planets.

    We know now that the universe is full of orphan planets, so it would hardly surprise me if there are many such planets randomly drifting toward stars.

  20. New System: Inner/Outer Planets by 7bit · · Score: 1

    Perhaps KP's, Kuiper Planets. Which could start a whole new Planetary naming system based on regional distance from a star instead of what we have now. Everything round + blah between the Star and it's local Kuiper Belt type region would be either an Inner Planet or Solar Planet, everything otherwise fitting that definition but within the Kuiper Belt would be a Kuiper Planet and anything further than that would be an Oort Planet.

    That might even allow Pluto to be reclassified as a planet again, either a Solar Planet or Kuiper Planet. I really think this system, plus other basic details like roundness etc, could be a more useful system. It would also allow a way to keep the number of planets more manageable since we could mostly focus on the Inner/Solar Planet count for general public use without the number of them being too high to manage.

    New Planet types based on Region/Distance from star:

    Inner Planet or Solar Planet
    Kuiper Planet
    Oort Planet

    btw: I made a post as anon under the same parent post before this, then thought I should log in and elaborate. The previous post was:

    " They'll probably be called KP's. Kuiper Planets."

    It could be simplified even further yet while still retaining the benefit of greater number manageability for the public, which seems to be a concern for those making the definitions, while also giving actual useful information about the planet in its Type name.

    Define a Planetary Region around a star, that would apply to all stars (actual distance per star could vary depending on Factors), in which Planetary objects would be called "Inner Planets" and one more region beyond it in distance where such same type objects would be called "Outer Planets". The Type Name of the Planets would instantly give anyone information about its position relative to its star, which is perhaps more important than telling us it's size "Dwarf". This would solve the old problem of non-Sol Planets not technically being "Planets" while also giving the public a common class of Planets to focus on and more easily remember while still being able to address all the other planets if needed.

    Inner Planets
    Outer Planets

    1. Re:New System: Inner/Outer Planets by darkain · · Score: 1

      This is starting to sound a lot like Sailor Moon with the Inner vs Outer Senshi.

    2. Re:New System: Inner/Outer Planets by Will.Woodhull · · Score: 1

      The alchemists did something like this, on the road to the periodic table of the elements. So it could definitely be a useful way to develop telescopic science.

      In a few decades we could then make a distinction between astronomers who accept a rationally based taxonomy of orbital objects, and "alastronomers" whose thought processes are mired in the old school searches for definitions that make distinctions between Pluto, Ceres, etc and Mercury, Mars, etc. Not to mention the hair-splitting the alastronomers use to keep from admitting that the Earth and Moon are a binary planet such that the orbit of either one around Sol has a strong sinusoidal component.

      --
      Will
    3. Re:New System: Inner/Outer Planets by Damarkus13 · · Score: 1

      Not to mention the hair-splitting the alastronomers use to keep from admitting that the Earth and Moon are a binary planet such that the orbit of either one around Sol has a strong sinusoidal component.

      I thought the distinction was that the center of the Earth and Moon's mass was still within the physical circumstance of the planet. While binary planets have that center of mass somewhere between the planet's. That doesn't seem like splitting hairs to me. That seems to be a pretty clear distinction.

    4. Re:New System: Inner/Outer Planets by Anonymous Coward · · Score: 0

      A lot of astronomers are not fans of the inside versus outside position of the center of mass, because it depends on distance as much as the relative size of the two bodies. You can take any two unequally sized bodies, and if you move them far enough apart, you will get a center of mass outside the bodies. There isn't really any compelling reason to need a distinction anyway, because all moons affect the parent planet's orbit and position, it is just a matter of degree.

      At least when talking about planets in the solar systems, there are a lot of times papers need talk about different groups of body within the solar system, and some amounts of standard categories simplify language. For now, if one wants to talk about relatively large moons, one can point to just Earth and Pluto, with no special name needed.

    5. Re:New System: Inner/Outer Planets by Anonymous Coward · · Score: 0

      Not to mention the hair-splitting the alastronomers use to keep from admitting that the Earth and Moon are a binary planet such that the orbit of either one around Sol has a strong sinusoidal component.

      You place way too much importance on terminology, and are acting like it changes things that it does not. Regardless of whether or not the Earth-Moon system is called a double planet, astronomers are quite aware of the mutual influence. The name doesn't change the existence of the effect. There is no need to clarify that one is talking about the Earth and Moon when talking about such dynamics in literature, as one just talks about the Earth and Moon. Beyond Pluto and Earth, there is not some long list that needs to be consolidated into a specially named category. Not to mention that the influence between the Earth and the Moon exists between all planets and their moons, just that in those cases it is a stronger effect with no qualitative difference.

      And there is no need for a massive schism if future astronomers need to group things differently. Either papers will de facto change the definition, or papers will start using a new term. The terminology is just there to save the effort of listing out every member of a category being discussed, and papers more than capable of coining new categories if it makes it easier to write and read. But beyond the succinctness of language, it doesn't make much difference one way or another how things are grouped.

    6. Re:New System: Inner/Outer Planets by Will.Woodhull · · Score: 1

      I have read your post and understand that it is, alas, representative of contemporary astronomy's position wrt the pairing of the Earth and Moon as not being significantly different from, say, the pairing of Mars and Phobos.

      But I take solace in the fact that the Moon is spiralling away from the Earth and long before the death of the Sun makes all this insignificant, the Earth and Moon will, in fact, become a binary planet. According to the precepts of contemporary astronomy.

      It does seem extremely odd that what will become true in the future is considered false at present. Especially as the increase in distance that will make the Earth - Moon a binary planet will also diminish the now powerful effects each has upon the other.

      --
      Will
    7. Re:New System: Inner/Outer Planets by Anonymous Coward · · Score: 0

      Will there be some more cats to help them?

    8. Re:New System: Inner/Outer Planets by Anonymous Coward · · Score: 0

      Would you be willing to settle for Dwarf-ary Planet?

    9. Re:New System: Inner/Outer Planets by SharpFang · · Score: 1

      " the Moon is spiralling away from the Earth and long before the death of the Sun makes all this insignificant, the Earth and Moon will, in fact, become a binary planet."

      With growing distance gravitational influence between two bodies gets weaker, that means distant Moon would influence Earth orbit even less than it does now, and the centre of rotation between the two would move even further towards Earth's core.

      --
      45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
    10. Re:New System: Inner/Outer Planets by Anonymous Coward · · Score: 0

      and the centre of rotation between the two would move even further towards Earth's core.

      You should look at the actual math instead of just vague hand waving, because it is just the center of mass which is not that hard to figure out. The barycenter is be r=a/(1+m1/m2), where a is the separation (semi-major axis in elliptic orbits). If you take any two bodies and separate them more, the center of rotation moves further from the center of the bodies. This is a reason some astronomers argue against the barycenter being used in the definition, is because it only very indirectly involves the size of the moon and instead is just a matter of a separation (a very small moon would have to go outside the Hill sphere before it can move the barycenter above the planet's surface).

    11. Re:New System: Inner/Outer Planets by Anonymous Coward · · Score: 0

      It does seem extremely odd that what will become true in the future is considered false at present. Especially as the increase in distance that will make the Earth - Moon a binary planet will also diminish the now powerful effects each has upon the other.

      Which is why a lot of astronomers think the barycenter location is a bad way to define double planet. Nothing qualitatively changes when the barycenter moves outside the parent body. Jupiter isn't special because its orbit is about a point above the surface of the Sun. Planets and other bodies with the barycenter located below their surface still wobble, and orbit the parent start in a sinusoidal path. So even those that have used the barycenter definition before don't place much weight on it. People on the internet spend way more time arguing about it, just like the issue with Pluto, than actual astronomers because the it has no implications for science and amounts to just a label.

    12. Re:New System: Inner/Outer Planets by Ramze · · Score: 1

      Modern astronomy is still clinging to the historical method of naming things according to their influence on and by their surroundings. Yes, it's silly. I'd rather a system that describes bodies by their characteristics instead of their locations relative to other objects.

      Phobos is just an asteroid captured by Mars, but because it's a satellite of Mars, it is classified as a moon. Some large moons around gas giants like Triton are thought to have once been planets or dwarf planets. Obviously, there's a huge difference between Titan with its large diameter and thick atmosphere and the tiny, irregularly shaped Deimos. Yet, they are both moons. The current system cares nothing for their characteristics or how they were formed.

      Your notion regarding the Earth/Moon system having a different classification in the future than it does today is no more relevant than if Mars were to be captured by Jupiter in a few billion years due to orbital instability. We'd then call Mars a moon instead of a planet. Odd, perhaps, but that doesn't mean we should start calling Mars a Jovian moon in the meantime - even if we had mathematical models proving it was going to happen. Even more odd -- if a Jovian moon were to be hurled into deep space, there is no official designation for what to call it at that point. Rogue planet, sub-brown dwarf, and interstellar planetary body are merely suggestions.

      To say that the Earth and the Moon have a special relationship is obvious, but it doesn't warrant any extraordinary classification given the absurdity of the current system. The Moon does indeed orbit Earth as evidenced by the barycenter being inside Earth as well as the Earth being the more massive of the two objects. The Moon is also tidally locked to Earth as most moons are. Yes, as you point out, both the Earth and the Moon have a sinusoidal/elliptical orbit around Sol, but I'd argue that it's not only insignificant, but its shape would change entirely if Earth/Moon were a greater distance from Sol. Earth's orbit only shows a tiny wobble while the Moon's is more pronounced, but more importantly - the shape of the Moon's orbit has little to do with the mass of the moon itself. At its current distance from Earth, given the masses and positions of Sol and Earth, any satellite would have a stronger gravitational influence from Sol than from Earth. However, if we moved Earth and the Moon to a distance say... in place of Jupiter, Sol's influence would be less, the barycenter between Earth and the Moon would stay the same, but you'd instead see a true looping orbit path for the Moon around the Earth as Earth's gravity will be significantly stronger than the Sun's at that distance. Some of Neptune's outermost moons also have a sinusoidal path around the sun, but again, it's more to do with the masses and distances to Neptune and Sol than anything unique about the moons in relation to Neptune. Alternatively, over 4 billion years ago, the Earth/Moon system would have had a barycenter closer to Earth's core and the distance between the Earth and Moon was shorter, making Earth's gravitational effect on the Moon much stronger. I haven't done the math, but given the distances, I'd bet the Moon's orbit at that time was more influenced by Earth than Sol as well and took a different shape around Sol.

      http://en.wikipedia.org/wiki/D...

      Your argument that the Earth and Moon have a special relationship in our solar system is valid, but your argument to classify that relationship as a binary planet is flawed primarily because there currently is no such formal classification. One was proposed for Pluto because the barycenter for it and its moons is outside of Pluto, but that proposal was abandoned. Pluto is a dwarf planet with moons instead of a binary planet or even a binary dwarf planet with Charon. The barycenter idea isn't a rule - it's just an arbitrary argument which wasn't strong enough to convince a committee that it was important enough to warrant

    13. Re:New System: Inner/Outer Planets by Will.Woodhull · · Score: 1

      tl;dr. I did read the first few paragraphs.

      Significant findings in what I did read:

      Somehow parent poster managed to mistake grand-parent's position with regard to using the innie-or-outie barycenter as a point of distinction between a moon and a binary planet. GP was very definitely saying that such a distinction was pointless. Which seems to also be what PP is trying to argue. Which suggests that much of PP can be ignored; it is preaching to the choir but for some reason its author has been unable to see that. Perhaps his mind, which apparently is pretty clear much of the time when dealing with astronomy, was clouded by his emotions. Which do come through very strongly in PP.

      However the following calls for a comment:

      To say that the Earth and the Moon have a special relationship is obvious, but it doesn't warrant any extraordinary classification given the absurdity of the current system.

      While PP and GP agree on the absurdity of all this, PP is not seeing the importance that GP sees in the affects of promulgating this crap.

      GP's concern is that astronomy has a duty (as does every science) to present its truths clearly to everyone outside of its small scientific community. It cannot dismiss absurd representations in its jargon as unimportant by arguing that all astronomers can see the fallacies and just ignore them. That is a travesty; astronomy needs to provide college students, high school students, grade school students, and kindergarteners with an accurate representation of its findings and not some mumbo-jumbo absurdity like what PP has so eloquently described above.

      This is all the more poignant since the IAU brought this whole foolish argument up because in the wisdom of their final hours of their last big confab after many members had left to catch the bus home, they expressedly attacked the current state of general understanding of what defines a planet or a moon and replaced it with an even more absurd set of definitions meant for public consumption. To replace what has been taught in the schools. And now through posts like PP the community of astronomers are attempting to backpedal by claiming that none of this makes any difference anyway, since WE all know what we are talking about.

      What arrogant bullshit.

      IAU: you and you alone have the power to fix this mess that was made on your doorstep, in your name. Figure out what it is that should be taught to the youngsters today who might choose to take advanced astronomy courses tomorrow. Then make that public, with your full support behind it.

      --
      Will
    14. Re:New System: Inner/Outer Planets by Anonymous Coward · · Score: 0

      IAU: you and you alone have the power to fix this mess that was made on your doorstep, in your name. Figure out what it is that should be taught to the youngsters today who might choose to take advanced astronomy courses tomorrow. Then make that public, with your full support behind it.

      They can't fix a mess that isn't there, and is only in the minds of people arguing pointless things. They've already wasted too much time on it, much of which was prompted by public wanting a formal definition before they decided on one (there were years of articles saying "Is Pluto a planet, are astronomers going to take its status way? Astronomers say 'Why spend time on this instead of actual science?'").

      Figuring out what to teach youngsters is especially easy, as you could concentrate on teaching them actual science and results, which doesn't matter much how it is grouped. In intro courses, public outreach, and summer programs for kids, we spend less time than it takes to read one of these posts: "This is how things are grouped together, now lets talk about some of the cool things we know about each of these." Only on the internet do you find people spending so much effort to argue so much about what has so little impact on actual education and science efforts.

    15. Re:New System: Inner/Outer Planets by Ramze · · Score: 1

      No need to begin with tl; dr as it's obvious you either didn't read it or simply have a lack of reading comprehension. Odd that you'd bother to reply without reading and comprehending, though. You clearly missed my point entirely.

      My post was a response to yours, not its grandparent, so all references to such are moot. Mostly, I was trying to convey a general sense that modern astronomy lacks clear, descriptive definitions and designations - including one for "binary planet" which you were clearly arguing for.

      This gem is what I was specifically replying to:

      "But I take solace in the fact that the Moon is spiralling away from the Earth and long before the death of the Sun makes all this insignificant, the Earth and Moon will, in fact, become a binary planet. According to the precepts of contemporary astronomy."

      The Earth and Moon will absolutely, emphatically, undeniably NOT be considered a binary planet according to contemporary astronomy because THERE IS NO SUCH DESIGNATION.

      I hope this post was short enough and uses small enough words to get the point across for you.

      I apologize for attempting to enlighten you on your error while simultaneously agreeing with you that the current system is extremely flawed.

    16. Re:New System: Inner/Outer Planets by Anonymous Coward · · Score: 0

      The idea that everything needs to be separated into neat and clean categories and hierarchies is a dated approach to science. Not only do things not fit in such categories cleaning in most sciences and frequently one has to deal with a multitude of overlapping descriptions, names and categories because different properties are relevant to different people, but progress is found to march on even with such vagaries. It is sad to see it turn into a "think of the children" type argument too, as in my experience, and others as seen by another post above, it has no impact of formal education and events. And for better or worse, all of the stupid drama gets more people to read about stuff they would have skimmed over otherwise.

    17. Re:New System: Inner/Outer Planets by Will.Woodhull · · Score: 1

      Yes, "the stupid drama" is probably getting more people to read this stuff than would otherwise be the case.

      But the positions that have been expressed are now only being repeated. Let it go. A better astronomical taxonomy will undoubtedly come along in the next few years, possibly at the next IAU convention. Let it go, for now.

      --
      Will
    18. Re:New System: Inner/Outer Planets by Anonymous Coward · · Score: 0

      A better astronomical taxonomy will undoubtedly come along in the next few years, possibly at the next IAU convention. Let it go, for now.

      Speaking of repeating positions, this was already stated and implied by comments you've replied to. People act like astronomers will just dig in and don't want anything to change when the times change, yet the definition was explicitly worded to address only the solar system and leave a more general definition until advances are made in exoplanet observation. There is an expectation that the definition will evolve with time, as needed.

      Odd choice to make that reply to too, considering the post you replied too didn't have much repeated from previous posts...

  21. WOOT? by Anonymous Coward · · Score: 0

    They can spot planet orbiting stars lightyears away, but not big-ass planets in our own neighborhood. Why is that?

    1. Re:WOOT? by Anonymous Coward · · Score: 0

      For one thing, because they do not pass between us and their sun.

      Captcha: "brighter"

  22. Mod parent up by Anonymous Coward · · Score: 0

    Mod the parent up, the original poster got it pretty much completely wrong.

  23. Mining Planets by Anonymous Coward · · Score: 0

    I see potential for a couple of movies, or a tv series. So far most of the stories have either limited to the solar system, or gone to the stars. The happy medium range is now imaginable.

  24. Blame it on Braben! by Anonymous Coward · · Score: 0

    If he does not fix the Elite: Dangerous inter-system travel by adding jumps between stars or between objects distant > 5000ls I will not visit those stations.

  25. In other news by Anonymous Coward · · Score: 0

    Rest of Milky Way actually found to orbit Sun. Center of galaxy reclassified BETNO (Brobdingnagian Extremely Trans Neptunian Object).

    .

  26. Nibiru! by Anonymous Coward · · Score: 0

    Alien mother ship, hiding behind the sun. Nephilim illuminati rebel scum are insinuating themselves via pseudoscience into astrological extra planetary debate to influence NASA climate change science deniers so as to elect mitt romney the dark lord of the freemason teapartiers.

  27. down by Anonymous Coward · · Score: 0

    www.sohbetodalarim.net

  28. Dark matter by Anonymous Coward · · Score: 0

    Arent we talking about dark matter?

  29. New planets by Anonymous Coward · · Score: 0

    Can anyone say Wormwood?

  30. So what?! by vandamme · · Score: 1

    If they're out there, they are cold and dark, and really really far away. As long as they stay there, it makes no difference to us.