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Oldest Planet Ever Discovered

Posted by CowboyNeal on from the brand-new-old-stuff dept.

crymeph0 writes "NASA has found the oldest known planet in a globular star cluster in the constellation Scorpius. At 13.7 billion years old, it's just slighly (~1 billion years) younger than the universe itself. Get more info from HubbleSite"

30 of 370 comments (clear)

  1. Oldest for now. by jromz03 · · Score: 1, Interesting

    Given a few years or even a few decades, technology would have had improved vastly that I'm sure we will see more older ones.

  2. universe age by Anonymous Coward · · Score: 2, Interesting

    How do they know the universe is 14.7 billion years old?

    1. Re:universe age by Valar · · Score: 4, Interesting

      You judge the age of fairly close objects, using nuclear models, compare with red shifts. Then you look at the red shift of far away objects and try to extrapolate age, IIRC.

      --

      ====
      Crudely Drawn Games
  3. Having taken one semester of astrophysics... by Valar · · Score: 4, Interesting

    at not being an expert by any means, I wonder how they detected it. I assume (because it is so massive and in a binary system) they detected it by the normal "wobble" method. Does anyone know?

    --

    ====
    Crudely Drawn Games
    1. Re:Having taken one semester of astrophysics... by hesiod · · Score: 2, Interesting

      > it is a neutron star spinning just under 100 times per second

      I didn't read the second (Hubble) article. The entire star spins 100 times per second? I would think that this star (any star) would be pretty big, so is that possible? I would think that means it's surface would be going faster than light. Am I misunderstanding something?

    2. Re:Having taken one semester of astrophysics... by Thorsett · · Score: 2, Interesting

      Thanks. Science is a bit of a challenge to write for, because of the tight page constraints, but we do try to keep things as readable as possible.

      It has been very interesting to me to watch the NASA publicity engine on this one from the inside. A press release like this is not written by the scientists who are involved. Space Telescope has professionals who do this. In general, though, they do a pretty good job. The best site may be this one, which has much more detail than the short version of the press release.

      For those who want more technical detail, our 1999 paper discusses the observations that really confirmed the presence of the planet. The new paper updates this slightly with new constraints based on the white dwarf mass. Together with some work in the intervening years on explain the slight ellipticity of the neutron star/white dwarf orbit (using something called Korzoi pumping), these new results have led to the slightly smaller estimated planet mass.

      PS. All of the pulsar timing analysis is done on Linux...

  4. Heavy elements by ramk13 · · Score: 5, Interesting

    What struck me the most from reading about it is that enough heavy elements (Fe, Si, etc) were around at the time to form the planet. That was one of the main reasons it was thought that planets couldn't have formed that early - you only had light gases around. So apparently it doesn't take a few billions years of fusion to get enough solid material for a planet. I wonder what other changes this will bring about in terms of the search-for-life campaign. The window just got a little bigger.

    1. Re:Heavy elements by Random+Walk · · Score: 2, Interesting
      What struck me the most from reading about it is that enough heavy elements (Fe, Si, etc) were around at the time to form the planet.

      High-mass stars are very short-lived, and one can expect that the first supernova goes off within a few 100000 years (most heavy elements are from supernovae). It will take a lot of time to completely mix the heavy elements with the rest of the interstellar gas, but at least some small regions will become enriched with heavy elements rather quickly.

    2. Re:Heavy elements by ilikecaffeine · · Score: 2, Interesting

      There's an easy way to solve this whole problem. Redefine the Universe. If the Universe is everything we observe, instead of everything that exists, then you can say that the big bang started the universe. In other words, what we call the "big bang" is really just the oldest event that we have observed (directly or indirectly). That way, theorizing what happened before the big bang is meaningless, as it is of no consequence to our observable universe.
      Sounds kinda sneaky, but that's always the way I have thought of it.

    3. Re:Heavy elements by Betelgeuse · · Score: 2, Interesting

      Yes. This is true. But remember. . . most of these super-massive stars that we think formed early on in the universe formed Type II Supernovae. This means that the heavy elements (i.e. Fe and everything heavier) would be locked up in the core of the remnant (i.e. black hole or neutron star). This means that these elements can't really go into forming new things like planets. It probably wasn't until Type Ia supernovae (i.e. main sequence star accreting onto a white dwarf until it explodes) started forming that there was a lot of heavy element enrichment. . . and the thought is that these took a while to form (since the white dwarfs in the binary system would have to form first).

      --
      I couldn't tell if you were experimenting with poor-man's cryogenics or looking for the orange sherbet.
  5. I wonder... by mikeophile · · Score: 4, Interesting
    How many civilizations have looked at Sol with their telescopes and determined the presence of Jupiter from our star's wobble?

    Would they conclude that it was unlikely that life could evolve in this system for one reason or another based upon their own standards?

    1. Re:I wonder... by mikeophile · · Score: 4, Interesting
      I think you've missed the point.

      There are several planetary systems that we have discovered that have been ruled out as having evolved life as we know it.

      The system in the article is a prime example.

      The x-ray emissions from the pulsar would prevent life as we know it from ever starting, much less evolving.

      Those are our standards. We have only ourselves as a basis for comparison.

      Perhaps there are very alien forms of intelligent life that would not consider our system capable of supporting biology because we lack a strong x-ray source.

    2. Re:I wonder... by BlueWonder · · Score: 2, Interesting
      How many civilizations have looked at Sol with their telescopes and determined the presence of Jupiter from our star's wobble?

      To detect our sun's wobble, the other civilizations would have to understand the concepts of space and time. I think it is unlikely that extraterrestrial beings think in such categories.

      I mean, we humans already know (from quantum mechanics) that the concepts of space and time are of limited value as models of reality, although we cannot escape the way our brains are hardwired. Extraterrestrials will probably think in completely different categories, which are as much beyond our imagination as space and time are to them.

  6. Not necessarily by archeopterix · · Score: 3, Interesting
    What struck me the most from reading about it is that enough heavy elements (Fe, Si, etc) were around at the time to form the planet.
    The article says it's a huge gaseous object so perhaps the heavy elements weren't necessary.
  7. how would they know it had any heavy elements? by dido · · Score: 3, Interesting

    It could be, and most probably is a gas giant like Jupiter. If so, then why should its formation so early in the universe be such a big surprise? Jupiter itself is largely made up of light gases which would have been present in abundance in such regions in the early universe. The fact that there's a supernova remnant there (a pulsar, the article says) tells me that any heavy elements (if they are required) could have come from the results of that explosion.

    --
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    1. Re:how would they know it had any heavy elements? by astrophysics · · Score: 2, Interesting

      The standard theory of the formation of Jupiter involves the accretion of a 5-20 Earth mass core which they accumulated nearby gasses.

      The planet almost certainly formed before the pulsar went supernova.

  8. Re:In case of slashdotting - follow my sig by AndroidCat · · Score: 2, Interesting

    And if you want to avoid that whole NYT thing, just follow my sig. I've had the story since yesterday. :^P

    --
    One line blog. I hear that they're called Twitters now.
  9. Re:Heavy elements and eating into the timeframe by nimblebrain · · Score: 5, Interesting

    Well, they're begging the question somewhat, but it seems true that globular clusters metal deficient. Jupiter's atmosphere is 82% hydrogen, 14% helium and only a trace of heavier elements. Who knows what goes on at the core, but that would seem to indicate that planets don't need rock to form.

    That said, if we found some moons around it somehow at some point in the future, there would be a lot of questions that need answering.

    Is it worrying anyone else, though, how thoroughly we're cutting in to the upper estimate of the age of the universe according to Big Bang Theory? Prior guesses on the age of the universe in BBT were in the 9-12 billion range.

    Invoking tweaks on inflation theory and 'anti-gravity' via the cosmological constant, the upper limit has been moved up to 15 billion years. Now here we are with a planet... a close planet (all things considered, 7200 light years isn't that far away on a grand scale :), that's 13 billion years old plus star and cluster formation time, and some of the other observations from the furthest visible reaches coming back from ye olde Hubble... how much further can we cut into this without jeopardizing the 15 billion year estimate?

    Something to consider...

    --
    Binary geeks can count to 1,023 on their fingers :)
  10. When does a planet become a star? by Azahar · · Score: 3, Interesting

    I realise that it is a stupid question but I would like to know the answer.

    Obviously a star is luminous and a planet isn't but even a planet like jupiter emits more energy than it receives.

    As to what is luminous and what isn't.. well most people think of the visible spectrum but that is just because we judge visibility that way.

    So, when does a planet become a binary companion?

    --
    Cuiusvis hominis est errare; nullius nisi insipientis in errore perseverare.
    1. Re:When does a planet become a star? by rhfrommn · · Score: 2, Interesting

      That is most definately NOT a stupid question. A star is defined by core nuclear fusion. However, the definition of a planet is quite controversial. In particular what are the limits that differentiate a planet from a brown dwarf on the large end, and from a asteroid or comet on the small end.

      Astronomers are having discussions about this right now. It is not entirely clear to me what the final definition will be. The current leading candidate for the brown dwarf/planet dividing line is how they form. If you formed from gaseous contraction like a star you're a brown dwarf. If you formed primarily through accretion around a forming star you're a planet.

      On the low end it is even messier. Some say the difference should be if your self gravity makes you into a sphere you'e a planet, and if you're irregular shaped you're a asteroid or comet. But in that case several members of the asteroid belt along with some trans-neptunian icy bodies discovered the past 10 years would both qualify as planets.

      --
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  11. Re:Cosmic Microwave Background by grahamlee · · Score: 2, Interesting

    The Universe means the system that completely encloses all of our interactions and experiences. If we find something, it cannot not be within our Universe, as we could not interact with it. Therefore even if other Universes 'exist', they cannot exist within our experience.

  12. Normal planetary systems by Azahar · · Score: 3, Interesting

    Perhaps planetary systems evolving in dense star populations are significantly different to the solar system.

    Perhaps extragallactic planetary systems are significantly different to gallactic systems.

    There is no 'normal' until we have a real comparison. These extra solar giants are fascinating but are only 'visible' to us because of their size. My personal view is that for any planetary system to support technology and intelligence (preferably in the same species, lol) would have to have a gas giant to hoover up the junk within the system.

    Are you old enough to remember the surprises that planetary weather brought to us? I look for nothing less from our extrasolar kin. Those planets will knock the socks off us once we know about them properly.

    --
    Cuiusvis hominis est errare; nullius nisi insipientis in errore perseverare.
  13. That's no planet by ralphclark · · Score: 2, Interesting

    Hang on, how do they know it's a planet? Couldn't it be a stellar remnant, i.e. the core of a star that has had its outer layers blown off by a nearby nova or supernova?

    Considering that it's orbiting both a white dwarf and a neutron star, and I'd definitely consider both of those to be the ultimate "smoking guns", *and* that current theories deny the existence of sufficient "metals" for planet formation in that epoch, I'd say the astronomers concerned here are jumping to unwarranted conclusions.

  14. Re:Cosmic Microwave Background by KDan · · Score: 3, Interesting

    They could exist theoretically, and they could even have consequences on our universe. For instance, if the fundamental laws of physics are symmetrical to the extreme then we might find that each possible law exists in some parallel universe (meaning all possible universes with all possible combinations and variations on the laws of physics exist). None of these other universes would be anything we could interact with, yet they determine (by the particular combination of laws that they don't contain) the fundamental laws of our universe.

    Daniel

    --
    Carpe Diem
  15. Re:Cosmic Microwave Background by Matrix272 · · Score: 2, Interesting

    None of these other universes would be anything we could interact with, yet they determine (by the particular combination of laws that they don't contain) the fundamental laws of our universe.

    That hurts my head just thinking about it. So let me ask you this, if we discover it's theoretically possible to break one of the fundamental laws of physics, and do so, does the parallel universe spiral into oblivion (as we probably would also)?

    --
    "It's better to have a gun and not need it than need a gun and not have it." ~ Christian Slater, True Romance
  16. Space Monkey by August_zero · · Score: 2, Interesting

    This very much lends creditability to the argument that if there is or was intelligent life elsewhere in the universe, there is no guarantee that it would just happen to coincide with the time that we monkeys are hoping around on our world. We may very well indeed be alone if we arived late, or too early to the party so to speak.

    --
    On Wall Street they say "buy low, sell high" On the pad we say, "buy high, sell high" Isn't that somehow better?
  17. Not 12.7 billion years old by Anonymous Coward · · Score: 1, Interesting

    Really, there is no evidence given that this planet is actually a mere billion years younger than the universe. We know its mass, and we know that it orbits around a very old object, but it might have formed a mere hundred million years ago and been captured by the pulsar.

    This article is based on speculation and gross exaggeration.

  18. Re:It's astonishing what we can do these days by Thorsett · · Score: 2, Interesting

    Wow, a cynic on slashdot.

    As an author of the Science paper, I may be a bit biased, but I would suggest that the reason that it is exciting is precisely because it does verify predictions that came out of completely different observations a few years ago.

    Our radio pulsar timing work showed that this system was a triple, and the mutual gravitational interactions between what you can reasonably think of as the neutron star/white dwarf orbit and the neutron star/planet orbit allowed us to measure the inclination of the neutron star/white dwarf orbit and predict the white dwarf mass. The work of Ford, Rasio, Sigurdsson, and others on theoretical modeling of the system suggested that it had to be "young" (the white dwarf formed a few hundred million years ago).

    Hubble then went out and found the white dwarf, and showed that indeed, as predicted, it was both low mass and young. Classic science paradigm: predict and test. But if we were willing to live without that independent test, we could (and, actually, did) argue that we knew the mass of the planet some years ago. Now with the new test, it will be more widely accepted. And work will continue.

  19. Universe Geometry: Maybe those planets are young by Anonymous Coward · · Score: 1, Interesting

    Perhaps those planets are actually younger than our solar system.

    Suppose our universe is the surface of a 4 dimensional sphere.

    Now aim hubble along a longitude line. Eventually it should be able to see "the other side of the universe". If you increase the scan length beyond this, you'll start to see stars and planets that are actually closer to us (from the other direction) even though Hubble will say they're farther away. In essense, these planets will appear older than they are because light will take longer to get here.

    How would we know that something like this isn't going on? For all we know, some of those solar systems we've been seeing other there with jupiter sized planets might be our own.

  20. Re:Cosmic Microwave Background by Squiffy · · Score: 3, Interesting

    There's a difference between the laws of physics and the theoretical laws of physics. The laws of physics are unbreakable exactly because that is what we mean by a law of physics: if it can be broken, then it wasn't a law of physics in the first place. If we find it possible to break a theoretical law, it will simply point us in the direction of a deeper theory, which may or may not agree with the actual laws of physics.