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Strange Mini Solar System Found

starexplorer writes "In 1990, Penn State's Alex Wolszczan found the first exoplanets. But he never got much credit from mainstream researchers, because his planets (3 of them, roughly Earth-sized) orbit pulsars and hold no chance for harboring life. Now he's found a 4th object on the outskirts of the system, SPACE.com is reporting. Call it a planet, call it an asteroid, Wolszczan says, but call the setup a dark, eerie twin of the inner half of our solar system. Also in the same story, news of a brown dwarf just 15 times the mass of Jupiter that has a planet-making disk of stuff around it. Together, more problems for astronomers, who still don't have a basic definition for the word planet or a firm idea of what separates planets from stars."

33 of 373 comments (clear)

  1. TMBG by angst7 · · Score: 5, Funny

    I think They Might be Giants defined what it was to be a star fairly well.

    "The sun is a mass of incandescent gas
    a giagantic nuclear furnace..."

    --
    StrategyTalk.com, PC Game Forums
    1. Re:TMBG by Anonymous Coward · · Score: 3, Insightful

      The sun is a mass of incandescent gas
      A gigantic nuclear furnace
      Where hydrogen is built into helium
      At a temperature of millions of degrees

      Yo ho, it's hot, the sun is not
      A place where we could live
      But here on earth there'd be no life
      Without the light it gives

      We need it's light
      We need it's heat
      We need it's energy
      Without the sun, without a doubt
      There'd be no you and me

      The sun is a mass of incandescent gas
      A gigantic nuclear furnace
      Where hydrogen is built into helium
      At a temperature of millions of degrees

      The sun is hot

      It is so hot that everything on it is a gas: iron, copper, aluminum, and many others.

      The sun is large

      If the sun were hollow, a million earths could fit inside. and yet, the sun is only a middle-sized star.

      The sun is far away

      About 93 million miles away, and that's why it looks so small.

      And even when it's out of sight
      The sun shines night and day

      The sun gives heat
      The sun gives light
      The sunlight that we see
      The sunlight comes from our own sun's
      Atomic energy

      Scientists have found that the sun is a huge atom-smashing machine. the heat and light of the sun come from the nuclear reactions of hydrogen, carbon, nitrogen, and helium.

      The sun is a mass of incandescent gas
      A gigantic nuclear furnace
      Where hydrogen is built into helium
      At a temperature of millions of degrees

    2. Re:TMBG by Anonymous Coward · · Score: 3, Funny

      Could you throw the extra apostrophes you put in the "it's" into the Sun? kthx bye

    3. Re:TMBG by Anonymous Coward · · Score: 5, Informative

      Singing Science Records

      The Ballad of Sir Isaac Newton is also not to be missed.

  2. Superman by kevin-cs-edu · · Score: 3, Funny

    "Call it a planet, call it an asteroid or call it Wolszczan says, but call the setup a dark, eerie twin of the inner half of our solar system." It's Bizarro world, our solar system's dark, eerie twin.

    1. Re:Superman by Rei · · Score: 4, Interesting

      I would love to see some of these extrasolar systems; the more we see, the more variety it looks like there is in the universe. "Hot jupiters" which orbit right close to their stars and even possibly exchange matter; the heat swells them up to many times their normal size. Brown dwarfs which give their closest moons enough light to possibly harbor life, while burning their deuterium slowly. Supercomets - planet-sized cometary bodies with huge comas. Planets without stars. "Water worlds" - bodies like Uranus or Neptune in a hotter orbit. And all sorts of other things.

      I hope some day humans can see them in person. :)

      --
      Dear Lord: One of your creatures may be hurt tonight. Please let it be the other creature.
    2. Re:Superman by LBArrettAnderson · · Score: 3, Insightful

      I think most people have an over-obsession with how things are "defined."

      Together, more problems for astronomers, who still don't have a basic definition for the word planet

      I'm sure the astronomers simply don't care. It's not a problem; definitions don't change anything.

    3. Re:Superman by SirBruce · · Score: 3, Informative

      Uranus and Neptune, while they are gas giants, are much smaller and much further out than Jupiter and Saturn. As a consequence of this, their formation was much different. Instead of balls of mostly gas with a rocky core (at least, Jupiter had one initially even if it doesn't anymore), they are primarily huge many-Earth sized balls of ice and rock, which accumulated very thick atmospheres.

      They are probably a lot more like really big Titans than really small Jupiters. If they could be magically moved to the inner solar system, they would no doubt form huge oceans of water. But it would be difficult for such a planet to actually form that close to the sun in the first place with so much water.

      Bruce

  3. Planets from stars? by hobbesmaster · · Score: 4, Informative

    Someone please correct me if I'm wrong or over generalizing, but planet vs stars: stars have fusion, planets dont. Hence, a gas giant like jupiter is a planet but a brown dwarf is a star (there is SOME fusion going on, or there was in the past).

    Planet vs planetoid is another matter altogether... I'd love to know if theres been a 'real' standard proposed - regardless of whether pluto/charon are planets/moon or not.

    1. Re:Planets from stars? by Scott7477 · · Score: 5, Informative

      As far as a definition I found this:

      "Working Group on Extrasolar Planets
      Defintion of a "Planet"

      POSITION STATEMENT ON THE DEFINITION OF A "PLANET"

      WORKING GROUP ON EXTRASOLAR PLANETS (WGESP) OF THE INTERNATIONAL ASTRONOMICAL UNION

      Created: February 28, 2001

      Last Modified: February 28, 2003

      Rather than try to construct a detailed definition of a planet which is designed to cover all future possibilities, the WGESP has agreed to restrict itself to developing a working definition applicable to the cases where there already are claimed detections, e.g., the radial velocity surveys of companions to (mostly) solar-type stars, and the imaging surveys for free-floating objects in young star clusters. As new claims are made in the future, the WGESP will weigh their individual merits and circumstances, and will try to fit the new objects into the WGESP definition of a "planet", revising this definition as necessary. This is a gradualist approach with an evolving definition, guided by the observations that will decide all in the end.

      Emphasizing again that this is only a working definition, subject to change as we learn more about the census of low-mass companions, the WGESP has agreed to the following statements:

      1) Objects with true masses below the limiting mass for thermonuclear fusion of deuterium (currently calculated to be 13 Jupiter masses for objects of solar metallicity) that orbit stars or stellar remnants are "planets" (no matter how they formed). The minimum mass/size required for an extrasolar object to be considered a planet should be the same as that used in our Solar System.

      2) Substellar objects with true masses above the limiting mass for thermonuclear fusion of deuterium are "brown dwarfs", no matter how they formed nor where they are located.

      3) Free-floating objects in young star clusters with masses below the limiting mass for thermonuclear fusion of deuterium are not "planets", but are "sub-brown dwarfs" (or whatever name is most appropriate).

      These statements are a compromise between definitions based purely on the deuterium-burning mass or on the formation mechanism, and as such do not fully satisfy anyone on the WGESP. However, the WGESP agrees that these statements constitute the basis for a reasonable working definition of a "planet" at this time. We can expect this definition to evolve as our knowledge improves."

      It looks like this is as close as we're going to get.

      --
      "Lack of technical competence coupled with the arrogance of power, as usual, leads to no good end."
    2. Re:Planets from stars? by Rei · · Score: 4, Informative

      It's not that simple. Do you say "If there was ever a single Dt-Dt reaction, it's a star", or do we require continuous reactions? It's hard to put an exact cutoff on the sequence from planets to main sequence stars.

      All of the bodies get some heat from gravitational collapse as they condense. Once you get enough heat and pressure in a small enough area, you can get Dt-Dt fusion; when there is a "significant" amount, it's called a brown dwarf. However, a relatively small amount of hydrogen is deuterium. As it gets hotter and denser, you begin to get other types of fusion, and you end up with a main sequence star.

      The planet/moon distinction becomes even harder when you can't tell exactly what's a planet or star. Once we get to some of these "huge jupiters", there will undoubtedly be debates as to whether there is a measurable amount of Dt-Dt fusion going on or not.

      --
      Dear Lord: One of your creatures may be hurt tonight. Please let it be the other creature.
  4. Mini solar system by Scott7477 · · Score: 5, Insightful

    How can this professor not be considered mainstream?
    He's on the faculty at Penn State! Sounds like he must have ticked off the wrong people at some point in his career. Maybe he needs to hire a PR person.
    I would say that finding a planet orbiting any star would be significant news, regardless of whether said planet might harbor life.

    --
    "Lack of technical competence coupled with the arrogance of power, as usual, leads to no good end."
  5. semantics by Anonymous Coward · · Score: 5, Informative

    semantics seperates planets from stars from asteroids... Our language, not reality...

  6. Planet Definition by FiReaNGeL · · Score: 4, Funny

    Astronomers don't have a planet definition? Here's one! Planets are round, asteroids aren't! How's that ? :)

  7. Definition by null+etc. · · Score: 5, Funny
    ...or a firm idea of what separates planets from stars.

    Space. Quite a bit of it, I hope.

    Oh, you meant what criteria separates planets from stars?

    Well, I definitely would much rather live on one than the other. Is that a good definition?

    1. Re:Definition by hcdejong · · Score: 4, Funny

      Planet X
      Ah, but then we'd have to send...

      Duck Dodgers in the 24 1/2th Century!!!

  8. Star vs Planet by imemyself · · Score: 3, Interesting

    Would a star not be any object that makes light on its own(ie, not reflects it)? IANAA(Astronomer)

    --
    Every time you post an article on Slashdot, I kill a server. Think of the servers!
  9. No chance of life? by suso · · Score: 4, Interesting

    because his planets (3 of them, roughly Earth-sized) orbit pulsars and hold no chance for harboring life.

    I wish people wouldn't say things like this. Humans barely have a grasp on what life really is and what conditions it can exist under, especially off our own planet. So how could we make a judgement that life couldn't exist around a pulsar, despite its homo-sapien threatening conditions.

    1. Re:No chance of life? by vwjeff · · Score: 5, Funny

      Acutally there are only two forms of life possible.

      According to whom?

      The only life we can be certain of is our own. Even then I sometimes wonder if I really exist. I guess I must because I am posting this, or am I?

  10. How insensitive! by Anonymous Coward · · Score: 5, Funny

    ..a brown dwarf just 15 times the mass of Jupiter..

    Please, "African American little person with a weight problem" is a little more appropriate and a lot less offensive, don't you think? Sheesh.

  11. Well Obviously by Madcapjack · · Score: 5, Funny
    Well Obviously this old dying star system is the original home of our species. We're just the descendents of the marooned colonists who found that their pyramid space-ships had suddenly (and quite inexplicably) turned to stone.

    Go figure.

  12. Stars generate energy by Man+in+Spandex · · Score: 5, Informative

    At least according to Wikipedia

    Scientifically, stars are defined as self-gravitating spheres of plasma in hydrostatic equilibrium, which generate their own energy through the process of nuclear fusion.

    Using this simple definition, it seems to apply to most stars out there? Correct me if I'm wrong or if the definition provided isn't accurate enough.

    1. Re:Stars generate energy by YU+Nicks+NE+Way · · Score: 4, Informative

      That works quite well for objects above about 25 Jovian masses. (In isolation, yadda yadda yadda) At that size, the body is large enough to support sustained thermonuclear fusion of species other than D+D->He3. Such bodies quickly heat up, becoming true red dwarf stars.

      Object smaller than about 13 Jovian masses never exhibit any sustained fusion. Those objects are planets if they orbit a star or a stellar remnant. (They are "sub-brown dwarfs" if they don't orbit a star.)

      Objects that sit between the 13 and 25 Jovian mass boundaries are in a grey area. They do exhibit sustained fusion, but only of D+D pairs. There isn't much deuterium around, though, so they don't ever heat up very much. Moreover, since they never engage in H+D->T and H+T->He3 fusion, they don't engage in the fusion reactions which are the signature of "real" stars. These are brown dwarfs -- not planets, because they do heat themselves up with fusion reactions, but not stars, either, because they don't fuse H.

  13. I am picturing... by spankey51 · · Score: 3, Funny

    A small gathering of Mini Coopers around a campfire in europe... Or something...

    --
    -ubuntu others as you would have others ubuntu you.
  14. The definitive definition by Profane+MuthaFucka · · Score: 5, Insightful

    A planet:
    -is a non-fusor
    -has sufficient mass to be roughly spherical due to gravity
    -orbits a fusor
    -isn't already referred to as any other type of object by convention
    -isn't associated through orbital composition or other general characteristics with another general group of non-planet objects (i.e. Vesta, though spherical, is associated with other objects known as asteroids, which are not massive enough to be spherical, and are therefore not planets. Vesta also is not a planet, because of the previous rule. It is by convention known as an asteroid, therefore it's not a planet.)

    My source for this definition is myself, and I deem it sufficient for sparking a major discussion, and possibly for other things as well.

    --
    Fascism trolls keeping me up every night. When I starts a preachin', he HITS ME WITH HIS REICH!
  15. Why on Earth does the name matter? by TechyImmigrant · · Score: 4, Interesting

    We started out with a limited number of names for things. Planets, stars, the sun. They we found some more things like comets and asteroids.

    Now we've found lots of things that come in between, requiring a different form of classification. The only problem is that people are trying to squeeze the definition of things we know about into a limited naming set.

    To name something doesn't mean we understand it and being unable to name something doesn't mean we don't understand it.

    People should stop worrying and be happy that we can describe these objects to a higher level of detail than can be described using the existing names we had for things floating in space.

    --
    Evil people are out to get you.
    1. Re:Why on Earth does the name matter? by T-Ranger · · Score: 4, Funny

      Hence forth, all space boddies will be known as "thingies".

  16. What separates planets from stars by pronobozo · · Score: 5, Funny

    "who still don't have a basic definition for the word planet or a firm idea of what separates planets from stars."


    One is on fire and one isn't.

    Now hand over my research grant.

    --
    ------
    insert sig here,here, and here
  17. It shouldn't be that hard. by Corbin+Dallas · · Score: 5, Interesting

    problems for astronomers, who still don't have a basic definition for the word planet or a firm idea of what separates planets from stars.

    It's not as sexy as having a word like "planet", but all this confusion could be eliminated with a basic classification system that took into account distinguishing characteristics besides just it's mass.

    As an example, one could define these objects through two primary attributes: The body's mass and the mass of that which it orbits. As I don't have exact mass data at hand, this example will use the following over-simplifications:

    S = Solar Mass
    G = Gas Giant Mass
    R = Rock Planet Mass
    M = Minor Mass ( appx Phobos to Pluto )
    A = Asteroid Mass
    D = Debrit ( 1m or smaller )

    Of course, the real system would use exact scientific measurments rather than these crude examples.

    Earth = SR ( Rock Planet Mass orbiting a Solar Mass )
    Jupiter = SG ( Gas Giant Mass orbiting a Solar Mass )
    Pluto = SM ( Minor Mass orbiting a Solar Mass )
    Titan = GR ( Rock Planet Mass orbiting a Gas Giant Mass )
    etc
    etc

    You could even create a symbol to represent the galactic center, which could be used in relation to stars and other free roaming bodies. Binary stars can be represented using SS, since they're orbiting each other.

    Anyway, the point is that you can not come up with solid definitions of these bodies on mass alone. Take into account other major factors as this example does.

    --
    Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote.
  18. Re:Solar? It's not Solar at all, morons by RubberDogBone · · Score: 4, Interesting

    It's that reporter for Space.com, Robert Roy Britt.

    He has a habit of using the word "solar" for non-solar topics, and of course the Space.com stories end up on the wire services and are repeated by hundreds of TV talking heads. All that does is make the problem worse. It's bad enough that most people don't even know the name of their star. We don't need them attaching that name to totally unrelated objects.

    Here's an unedited quote from him regarding a complaint on the same subject from one of his previous stories:

    Thanks for your note. You are correct in the strict sense, but astronomy and language are evolving. We now know of many other systems that look familiar. And many astronomers have come use the term "solar system" to describe other planetary systems. It's becoming a bit like Kleenex in its generic usage.

    I'm all for accuracy, but I think also that language is fluid, and if astronomers use the term interchangeably, then I think it's best I do so,
    too. I also find it the most convenient term to convey a system of planets with a central star -- and there are hints of lone, wandering planets not
    hosted by a star, so a distinction is helpful (at least until the latter situation is sorted out). I appreciate hearing from you because notes like
    yours help me frame my approach to writing.

    --
    Sig for hire.
  19. Leave differentiation to the experts? by Meetch · · Score: 3, Interesting
    Looking here, I see lots of what I would normally consider insightful input into what could be eventual definitions of stars, supergiants, planets, asteroids and pebbles. However, as was mentioned the definitions are simply going to have to evolve with our understanding.

    Would The Earth cease to be a planet just because something threw it forever out of our solar system? (Well actually, for now almost certainly yes, 'cos then there'd be no humans to define "planet" ;). At what point does an asteroid have to collect enough dust and become spherical enough to become a planet? Not all planets are spherical - Mercury is more elliptical from memory, thanks to effects of being in close proximity to a star... errr, the Sun. They wouldn't even have to necessarily spin - though that would help with roundness.

    Also from recollection of earlier dictionaries, our moon would become a planet (or planetoid?) if some catastrophe yanked it away from the earth, to forever go around the sun - because it wouldn't then be a body orbiting a planet - a simple, but rock solid definition IMHO. Oh but hang on, what about all those little rocks orbiting Earth???

    In that respect remember that some definitions are probably inherently transitional, depending on what they are doing. If it's a rock orbiting a sun, it's an asteroid, around a planet then it's a moon, if it's become round (has enough gravitational pull to hold itself together?) then it's a planet if it's going around a Sun - or is it, because what if the planet escapes?

    I believe the dictionary definition of "moon" is pretty good already, but as for the rest... I hope you can see what I mean because it gives me a headache! If we set a strict definition of a type of celestial body, and then suddenly we discover that there are so many more bodies that just don't quite fit the category, then what? I don't fancy taking liquid paper to my dictionary. So I will leave splitting those hairs to the experts.

  20. Definition by GrabtharsHammer · · Score: 5, Funny

    planet n.
    Big lump of stuff, roundish, spinning a bit, usually orbiting a, um, star thingy. Might have aliens on, but probably not. Probably.

  21. In Japanese by dirtsurfer · · Score: 3, Informative

    the word "hoshi" means both planet and star.

    So we live on a hoshi, and all the bright things you see in the sky are also hoshi's.