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Supernova May Explain How Planets are Formed 54

ExE122 writes "A young pulsar that formed from a supernova which happened about 100,000 years ago and is sitting 13,000 light years away may solve some questions about the origins of Earth. From the article: 'Scientists think they have solved the mystery of how planets form around a star born in a violent supernova explosion, saying they have detected for the first time a swirling disk of debris from which planets can rise. The discovery is surprising because the dusty disk orbiting the pulsar, or dead star, resembles the cloud of gas and dust from which Earth emerged. Scientists say the latest finding should shed light on how planetary systems form.'"
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Supernova May Explain How Planets are Formed

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  • by linguizic ( 806996 ) * on Wednesday April 05, 2006 @06:01PM (#15071253)
    Form the article:
    Chakrabarty said the debris disk most likely formed from metal-rich material that failed to escape the supernova. The disk resembled that seen around sun-like stars, leading researchers to conclude it might spawn a new planetary system.

    Radiometric dating points to the earth's inception being ~4.6 billion years ago. I want to know if the U238 that exists today was created as a result of the supernova that blew apart the solar system that provided all the matter for this one. All the U238 that we've found in this solar system so far points to our entire system being ~4.6 billion years. If the U238 was in fact created by this supernova, then we can't say that the earth as a planet is ~4.6 billion years old.

    I really hope no creationists read this, I don't mean to give them any fodder.
    • by eln ( 21727 ) on Wednesday April 05, 2006 @06:02PM (#15071266)
      This new data conclusively proves that the Earth was, in fact, created last Tuesday. Researchers are still double checking the math, though.
    • How could that parent post be "offtopic"??

      It's a legitimate question that can be asked, though I think that the radiometric measurement takes the thought into account already (admittedly I don't remember the detail of such measurement).
    • Stars fuse H into He and so forth all the way up to lead (Pb). Lead is a problem because it inhibits further reactions. Any elements past lead come from when the star explodes.
      • by techno-vampire ( 666512 ) on Wednesday April 05, 2006 @07:00PM (#15071669) Homepage
        Not lead, iron. In order to fuse iron to anything higher, you have to add energy, rather than getting energy from it. Once a star starts creating iron in its core, it takes only about 24 hours to burn as much as it's going to. Then, as it contracts, the iron heats up until it suddenly breaks down into helium, taking back all the energy it's given out. That causes a catastrophic collapse, followed by the explosion known as a supernova. Among other things, this generates enough energy to fuse iron into higher elements, so that all elements above iron (including lead) to be the product of a supernova.
    • Has nothing to do with the earth's age. The article is only talking about the formation of planets around a supernova - and that is not what happend in our solar system.
    • by jnaujok ( 804613 ) on Wednesday April 05, 2006 @07:02PM (#15071687) Homepage Journal

      The explosion in the article happened 13,000 light years away. That's a measure of distance. This has nothing, repeat nothing, to do with our solar system. Our solar system was formed as the result of a supernova *more* than 5 Billion years ago. The U238 on our planet is the remnant from *that* supernova, not from one that happened 100,000 years ago.


      On the other hand, if your rather confused grammar is trying to say that the precursor star to the sun (or many precursor stars as supernovas often occur in groups -- being formed from groups of super-giant blue-white stars [see Pleides]) created all the U238 4.6BYA and that the Earth must therefore be less than 4.6BY old. If that's the case, then yeah, maybe the Earth itself is less than 4.6BY old. So what? It just means that the rock it formed from took a little while to condense into its current shape. It's not like the Earth formed, oceans, mountains, and all on Tuesday the 13th of July, 4,600,000,000 BC. It takes tens of millions of years for the matter to acrete into a planet.

      If you're wondering in general did all the U238 come from a supernova, then the answer is simple. Yes. So did every element heavier than iron on the periodic table. A supernova is the only place those elements can be formed in nature (at least in any quantity.)

      Iron is the energy dead end. When a star runs out of hydrogen, it starts "burning" Helium, when it's out of Helium it starts "burning" boron, and carbon, and oxygen into heavier elements. But when it hits iron, that's the end of the road. There's simply no more energy to get out by fission or fusion. The star is effectively dead. The trick is, if a star can actually reach the silicon "burning" stage where iron is the byproduct, then it's so massive, it's going to go supernova anyway. Part of the energy of the supernova goes into fusing Iron and other leftover bits to produce elements higher on the periodic table. This *costs* energy, so the only place it can happen is a supernova. Thus every element higher than iron (Silver, gold, platinum, lead, mercury, uranium, praseodimium, lanthanum, radium, etc.) had to be formed in a supernova.

      Welcome to the universe. You are made of exploded stars. If there had been no Phase I (metal-poor) stars, there would be no planets, no humans, no nothing, because everything else is made of their exploded corpses.
      • Welcome to the universe. You are made of exploded stars.

        This begs the question; which elements heavier than iron (#26) are essential components of the human body?

        According to Wikipedia [], we contain trace amounts of cobalt(27, part of vitamin B12), copper(29), zinc(30), selenium(34), bromine(35), strontium(38), molybdenum(42), iodine(53), and lead(82). All of these (except strontium, it seems) can cause medical problems if absent. (yes, even lead []!)

        You also may contain traces of arsenic(33, if you p
      • Not every element greater than Fe was created in a supernova explosion. Much might of been created by the collision of Neutron Stars [].
        • What's with the use of the word "of" instead of "have"?

          It makes me cringe, and English isn't even my native language...
          • It's a common fallacy that's crept into the English written language because of the poor pronunciation and grammar that runs rampant in American Public Schools. People are often heard saying, "I should 'av' done that," when they say, "I should have done that." The "av" is pronounced with a sound very close to "of" and eventually the idiom becomes automatic.

            People then write down what they have repeatedly wrongly been saying without being corrected because of the current belief that "self-esteem is more im
        • An interesting article, but it says nothing about creating heavy metals. In fact, it's impossible for a neutron star to create anything but hydrogen. Even if the star was somehow torn to bits, the neutrons would simply decay to a proton and electron (elemental hydrogen). When two neutron stars collide, nothing comes out but radiation and maybe a small handful of neutrons. If anything, most collisions will result in black holes, which aren't going to be contributing much of anything of consequence to the uni
    • You seem a mite bit confused. The article isn't saying that the Earth was created by the mentioned supernova. It saying that this discovery might help us figure out how planets come into being; of which the Earth is one.

      That 100,000 year figure has nothing to do with the 4.6 billion year estimate - two different supernovas.

      And... Yes, the extant U238 was most likely created by the supernova that created our solar system.

    • by slughead ( 592713 ) on Wednesday April 05, 2006 @07:34PM (#15071913) Homepage Journal
      Radiometric dating points to the earth's inception being ~4.6 billion years ago.

      Radiometric dating.. I guess that's the first stage in how planets make other planets.
    • Funny maybe - but certainly not interesting.

      TFA talks about the observed disk providing evidence that planetary disks are more stable than previously thought - NOT that the supernova involved in the creation of THAT specific disk also created our solar system.


      "It shows that planet formation is really ubiquitous in the universe. It's a very robust process and can happen in all sorts of unexpected environments," said lead researcher Deepto Chakrabarty, an astrophysicist at the Massachusetts Insti

    • Radiometric dating points to the earth's inception being ~4.6 billion years ago. I want to know if the U238 that exists today was created as a result of the supernova that blew apart the solar system that provided all the matter for this one.

      The U238 was definitely formed in a supernova. Basically all heavy elements were.

      It should be noted, however, that this implies that the solar system is at least 4.5 billion years old. It can't be less.

      This is what's stated by radiometric dating, anyway. They can only d
    • I gues it all depends on what your definition of "old" is. Different things can have different ages. The uranium was formed in a supernova explosion, but I doubt that a single supernova provided all of the heavy elements that make up the earth. Much more likely, way back in the "good old days" when what would become the solar system was just a tiny part of a vast cloud of gas on the outskirts of the galaxy, many supernova were happening in stellar nurseries, each of which ejected heavy elements which contri
  • by Giant Ape Skeleton ( 638834 ) on Wednesday April 05, 2006 @06:01PM (#15071257) Homepage
    Hopefully this will put to rest the "static cling" model of planet formation once and for all!
  • by paladinwannabe2 ( 889776 ) on Wednesday April 05, 2006 @06:14PM (#15071368)
    A note about the article is that any planets that might be formed from the cloud of debris would be orbiting a pulsar [] Even if it has planets, it doesn't tell us much about how our own solar system could have developed.
  • by Anonymous Coward
    "Supernova May Explain How Planets are Formed"

    Huh? And here I thought it was when a mommy planet and a daddy planet got together. Although how they get anything done with all those astronomers looking on is a complete mystery.
  • Not habitable? (Score:5, Insightful)

    by Beryllium Sphere(tm) ( 193358 ) on Wednesday April 05, 2006 @07:02PM (#15071684) Homepage Journal
    The article says that any planets which form are likely to be uninhabitable because they're, to put it bluntly, made out of reactor waste.

    Why couldn't you have radiation-tolerant species []?

    If they went on to have multicellular descendants, then intelligent ones, those descendants could build cheap nuclear spacecraft including Orion-class vehicles and operate them without fear of radiation poisoning.
    • Why couldn't you have radiation-tolerant species?

      Good question.

      Because maybe non-radiation tolerant species are more probable in the universe (you know... Anthropic Principle [] and what not...)

      And that we came about first because life (or at least carbon life) has to evolve by radiation mixing up dna to create random evolution over time with favorable mutations taking over while the unfavorable mutations die out.

      Too much reaction to radiation over mutates us and kills us.
      Too little reaction, makes us not evol
    • Re:Not habitable? (Score:3, Informative)

      by Detritus ( 11846 )
      What do you think keeps the Earth as warm as it is? Reactor waste.

      The primary energy source of Earth is radioactive decay. The sun, gravity, and meteorite impacts all contribute some energy, as well, but not nearly as much as that provided by radioactive decay (estimated for the bulk Earth at around 6.18x10-12 watts/kilogram). .htm []

    • The article says that any planets which form are likely to be uninhabitable because they're, to put it bluntly, made out of reactor waste

      Yes and no, mostly no. The initial material is pretty radioactive, but that doesn't last long. Most of the radioactive isotopes have very short half-lives. Half-lives in the millions of years is rare.

      This means that a planet formed from the debris of a star that went supernova 100 million years earlier will not be that much more radioactive than Earth.

      So for all pr

  • by Kelson ( 129150 ) * on Wednesday April 05, 2006 @07:04PM (#15071700) Homepage Journal
    The whole accretion-disk-clumping-into-planets theory has been around for decades, and we've seen signs of accretion discs around stars before. What's new here is that such a disc has been found around the remnants of a star that's already gone supernova -- an event which would have destroyed any previous solar system.

    This is the missing link which explains why we've found planets around pulsars, because any planets formed earlier in the star's lifetime would have been destroyed in the supernova.
  • by spinfire ( 148920 ) <> on Wednesday April 05, 2006 @07:32PM (#15071899) Homepage
    Shortly after forming a number of planets, the Suprnova was shut down by pressure from NPAA (New Planet Association of the Americas). However, other services such as mininova have conveniently filled the niche. A spokesman for NPAA claimed that they would continue their ruthless domination until no new planets could be formed.
  • Scientists say the latest finding should shed light on how planetary systems form.

    They will ley us know for sure in a million years or so.

  • feel free to mod me offtopic, but I submitted this same story with NASA as the news source and it was rejected. Perhaps my title was less interesting. ight-form-around-super-novaed-stars/ []

There's no such thing as a free lunch. -- Milton Friendman