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Massive Diamond Found Orbiting Pulsar

Posted by timothy on from the think-of-the-street-value-of-this-mountain dept.

HairyNevus writes "A recent survey of pulsars has revealed a fascinating discovery of a millisecond pulsar in system PSR J17191438 that has stripped a nearby white dwarf star down to its very core. Although no longer visible, is still has the mass of Jupiter. The remaining core rotates its neutron star companion with a period of just under 2 hours, indicating extremely close proximity. Given this distance, scientists have calculated that the substance of the core must be very compact, and, without building up the point, they conclude it is made of diamond. One thing I found misleading about the article is that it refers to the core as having 'the size of Jupiter' and 'the mass of Jupiter.' Given their different densities (diamond vs. mostly helium), it would seem clear that their size (i.e. volume) differs."

25 of 204 comments (clear)

  1. Better Press Release by eldavojohn · · Score: 5, Informative

    One thing I found misleading about the article is that it refers to the core as having 'the size of Jupiter' and 'the mass of Jupiter.'

    Here's the correct Science Journal link and here is a better press release from the Max Planck Institute that clarifies:

    For the newly discovered pulsar, known as PSR J1719-1438, the astronomers noticed that the arrival times of the pulses were systematically modulated and concluded that this is due to the gravitational pull of a small orbiting companion, a planet. These modulations can tell astronomers several more things about the companion. First, it orbits the pulsar in just two hours and ten minutes, and the distance between the two objects is 600,000 km - a little bit less than the radius of our Sun. Second, the companion is so close to the pulsar that if its diameter was any larger than 60,000 km (less than half the diameter of Jupiter) it would be ripped apart by the gravity of the pulsar.

    So it appears that the article saying "size equivalent to Jupiter" (volume?) is wrong if the Max Planck Institute is correct in saying that its diameter has to be less than half the diameter of Jupiter.

    --
    My work here is dung.
    1. Re:Better Press Release by h4rr4r · · Score: 2

      Carats is both volume and mass. Diamonds have a fixed density.

  2. damn by Anonymous Coward · · Score: 4, Funny

    Now my wife will want it

    1. Re:damn by Dunbal · · Score: 3, Funny

      Too bad, DeBeers already bought it. Gotta keep those diamonds out of the wrong hands.

      --
      Seven puppies were harmed during the making of this post.
  3. Diamonds are not rare, not even on Earth. by Kenja · · Score: 5, Insightful

    Regardless of what the De Beers group wants you to think, diamonds are not that rare. Carbon is the most common element around.

    Still, its kinda nifty to see such a large chunk of the stuff.

    --

    "Have you ever thought about just turning off the TV, sitting down with your kids, and hitting them?"
    1. Re:Diamonds are not rare, not even on Earth. by buchner.johannes · · Score: 2

      Regardless of what the De Beers group wants you to think, diamonds are not that rare. Carbon is the most common element around.

      Hydrogen is the most common element, not Carbon. Or was that a hyperbole?

      --
      NB: The message above might reflect my opinion right now, but not necessarily tomorrow or next year.
    2. Re:Diamonds are not rare, not even on Earth. by Riceballsan · · Score: 5, Interesting

      Well they are actually rediculously common, were it not for a very very large percentage of the supply in the hands of a handfull of companies, and making a perfect undetectable forgery of a diamond is extremely easy with the right equipment. Without the right lobying and rules, forcing all manufactured diamonds to have a watermark to be distinguished as "fake", and having the actual supply in control of a handful of companies that intentionally release the supply slowly to keep demand high, Diamonds could easilly become cheaper then copper.

    3. Re:Diamonds are not rare, not even on Earth. by newcastlejon · · Score: 3, Funny

      Perhaps the parent meant on Earth, but that's also wrong, or perhaps they meant just the crust... nope, still wrong. Or maybe it's the entire Universe? Nope, distant fourth.

      Care to enlighten us Kenja?

      --
      If God forks the Universe every time you roll a die, he'd better have a damned good memory.
    4. Re:Diamonds are not rare, not even on Earth. by idontgno · · Score: 3, Funny

      I bet he meant that carbon is the most abundant element in diamonds. That's pretty much true.

      --
      Welcome to the Panopticon. Used to be a prison, now it's your home.
    5. Re:Diamonds are not rare, not even on Earth. by petman · · Score: 2

      He's not wrong, from a certain POV. He said 'common', not 'abundant'. One definition of common is 'most familiar'. In fact, as I look around from where I sit, most of the stuff I see are made from carbon-based materials - papers, plastics, fabric, wood. So, in a sense, carbon is the most common i.e. familiar.

      --
      Dropbox drops it like it's hot.
  4. Obligatory by Ironchew · · Score: 4, Funny

    These planets are a diamond dozen.

  5. Old Spice man says... by stonegrid · · Score: 2

    Look again, the planets are now diamonds.

  6. Time for a renaming... by Zephyn · · Score: 5, Funny

    We've just got to name the pulsar "Lucy" now.

  7. Re:Value by Forty+Two+Tenfold · · Score: 2

    About 20,999,999.9769 BitCoins.

    --
    Upward mobility is a slippery slope - the higher you climb the more you show your ass.
  8. Excellent news by Kittenman · · Score: 2
    Now we'll get private companies saying "hey, if we get into space there is some serious money to be made". That's how we'll finally get there, for keeps. And I'm serious. The future of space is in the hands of corporations, not governments. And that's how it should be.

    Pity I won't be around to see it, but can't have everything.

    --
    "The greatest lesson in life is to know that even fools are right sometimes" - Winston Churchill
  9. Re:Value by djdanlib · · Score: 2

    It wouldn't be sold in one piece. You can bank on that. Also, I bet ownership and "land" claims would be a really hot topic.

    If it were feasible to get it to a nearby stable orbit and not wreck the Earth or any of our stuff in the process, then it would cost an immense amount at first. Prices would get progressively lower as the technology evolved to "mine" and transport the pieces. The market would reach its saturation point eventually, too.

    Space diamonds would probably always cost more than diamonds originating here on the planet, though, because of how expensive it is to safely retrieve objects from space.

  10. Is it really diamond? by Xerxes314 · · Score: 2

    The phase diagram of carbon at extreme temperature and pressure is pretty much unknown. We don't even have any really good studies of liquid carbon. So it's entirely possible the core of such a white dwarf would be made of some other phase of carbon. See, for example, this figure of the carbon phase diagram from density functional theory, showing that over a terapascal, diamond is unstable. Stuff is not the same at the core of a star (even a small one) as in your backyard.

    1. Re:Is it really diamond? by Xylantiel · · Score: 4, Informative

      The answer is no it is not diamond.

      One issue is the one you point out, that the correct crystalline structure at high densities/pressures is not a diamond lattice. There is also the pesky fact that the inner portions of white dwarf stars are made of carbon and oxygen.

      One could actually go on and on because diamond is a covalently bonded crystal, while this stuff will be a degenerate electron gas containing an ionic crystal, much more like a crystalline metal.

      I study white dwarf stars for a living (yes really) and calling this stuff diamond is just idiotic.

    2. Re:Is it really diamond? by GRS1915+105 · · Score: 2

      As another astronomer who studies compact stellar remnants like white dwarfs (I tend to focus on the even denser neutron stars and black holes), I thought I'd add my two cents.

      If you look closely at the Science paper, you'll also find that they can't rule out that the companion to the pulsar is a Helium white dwarf, so it might not even be dominated by carbon/oxygen. We can also quibble about calling the low-mass white dwarf a planet, and in fact I had a long debate yesterday with a fellow astronomer about this very fact. While it's true that its mass is similar to those of planets, this is really the remnant of what was once a star. Its evolution to get to this point is extremely different from what most people (and astronomers) think of as planets.

      Finally, I'll point out that careful examination of the original paper also shows that this may not be the only known such object. This pulsar (rapidly spinning neutron star pointed our way)+ white dwarf is one example of an ultracompact X-ray binary. (The most extreme example of these systems has a white dwarf orbiting a neutron star every 11 minutes!). Some of the other ultracompact X-ray binaries could also be carbon/oxygen white dwarfs with masses less than 13 times the mass of Jupiter (i.e., what some astronomers loosely define as the upper limit for a "planet").

      I would not go so far as to call the press release idiotic. It has done a good job of bringing attention to this discovery, which is still extremely cool, even if "Planet Bling" is far from being true. Science communicators have a difficult job in walking the fine line between promotion and detailed argument.

    3. Re:Is it really diamond? by GRS1915+105 · · Score: 2

      I'd just like to point out that you are not quite right.

      You're correct that this is the remnant of a star, but then again that is true for all white dwarfs.

      Actually, this is a real white dwarf. But it's easy to get confused. Degeneracy pressure operates non intuitively. As a degenerate object loses mass, its radius will increase. Thus low-mass degenerate objects have a lower density than what astronomers typically talk about for a white dwarf.

      This object is actually the core of a white dwarf, where the white dwarf has loss much of its mass. The mass was transferred onto the neutron star, which is why it has spun up to become a millisecond pulsar.

  11. This isn't diamond the way you're thinking by MMORG · · Score: 3, Informative

    This isn't diamond in any sense that we usualy think of it. Yes, it's carbon atoms, and yes, they're "crystallized", but the core of a white dwarf is composed mostly of electron-degnerate matter where all of the electrons have been disassociated from their parent atoms and all the nuclei clump together, floating in a sea of electrons. This stuff has a density of roughly 1000 kilograms (2,200 lbs) per cubic centimeter. I imagine it would *catastrophically* decompress if you could teleport a chunk of it back to earth. It's not diamond.

    1. Re:This isn't diamond the way you're thinking by LordLimecat · · Score: 3, Funny

      I imagine it would *catastrophically* decompress if you could teleport a chunk of it back to earth

      I imagine people would pay to see that; I know I would.

    2. Re:This isn't diamond the way you're thinking by Benjamin+Shniper · · Score: 2

      Teleportation is a good point. How could we possibly get a spaceship that close to a pulsar? Maybe our spaceship is made out of diamonds to begin with?

      Hmm... It would be an ideal place for a planetary computer. You have a diamond, or maybe "metalic carbon" substrate for a planet the size of jupiter.
      Then you have a pulsar clock, and powersource.

      Perhaps that's really what we are looking at?

      -Ben

  12. Ooohhhh!! by jamiesan · · Score: 4, Funny

    PSR J1719-1438 went to Jared.

  13. Re:Value by nitehawk214 · · Score: 2

    It would be worth exactly what you can get someone to pay for it. No less, no more.

    Ask a stupid question...

    It would cost whatever DeBeers wanted to charge for it.

    --
    I'm a good cook. I'm a fantastic eater. - Steven Brust