Study: Uranus & Neptune Have Seas of Diamond—With Diamond Icebergs

By Andrew Moseman | January 22, 2010 5:47 pm

neptuneBoth Uranus and Neptune have quirky magnetic poles—they’re located about 60 degrees off the geographic pole rather than very nearby, like ours is. The reason, researchers suggest in a new Nature Physics study, could be that oceans of diamond—yes, oceans of diamond—cover our solar system’s two most distant planets.

The diamond idea isn’t a new one, but it’s a terribly hard question to study because you have to get diamond to melt in the lab to study it, and this experiment was the first to document the pressure and temperature at which that happens. The mineral is notoriously hard, of course, but there’s something more: Diamond doesn’t like to stay diamond when it gets hot. When diamond is heated to extreme temperatures it physically changes, from diamond to graphite. The graphite, and not the diamond, then melts into a liquid. The trick for the scientists was to heat the diamond up while simultaneously stopping it from transforming into graphite [Discovery News].

Doing so required not only extraordinary heat, but also extraordinary pressure. The researchers liquefied the diamond at 40 million times more than the pressure at sea level on Earth. When the pressure fell to only 11 million-times Earth sea level and temperatures dipped to 50,000 degress Celsius, solid chunks of diamond began to appear in the liquid [The Telegraph]. Because diamond is one of those rare liquids, like water, that is less dense as a solid than a liquid, solid diamond “icebergs” could float on to of the diamond seas on Neptune and Uranus.

Both planets have the conditions and the carbon to make this possible; each one is made from up to 10 percent carbon. And all that diamond would explain the out-of-whack magnetic pole, the scientists say. A huge ocean of liquid diamond in the right place could deflect or tilt the magnetic field out of alignment with the rotation of the planet [Discovery News].

Related Content:
80beats: Did Galileo Spot Neptune Two Centuries Before Its “Discovery?”
80beats: The Earth’s Oldest Diamonds May Show Evidence of Earliest Life
Bad Astronomy: A New Ring Around Uranus
Bad Astronomy: Did Herschel See the Rings of Uranus?

Image: NASA

  • Zachary

    I hear De Beers is investing in space travel.

  • Reginald B. Little

    These superb experimental results have been previously predicted and explained in “Treatise of the Resolution of the Diamond Problem” by Reginald B. Little (Progress in Solid State Chemistry, 2008). In the Treatise, a crystalline magnetically-ordered fluid (liquid) state of sp3 (diamond) carbon was proposed and explained to have greater density than solid diamond due to the fermionic nature and rotation of the sp3 carbon radicals of the diamond fluid (liquid) for the smaller fluidic (liquid) volume than the volume of the bosonically bonded carbon atoms in the bonded state of solid diamond. The Treatise explained the magnetic nature of such a sp3 carbonaceous (liquid diamond) fluid state and how the rotons of the carbon radicals of such diamond liquid cause their strong electromagnetic attractions for even greater density of the liquid sp3 carbon (diamond) relative to the bosonically bonded solid diamond. The Treatise unifies the various diamond syntheses via such dense quantum fluidic states during the direct (carbon liquid), the indirect (liquid catalytic iron, nickel, and/or cobalt) and the hydrogenous plasma (hydrogen plasma fluidic) formations of diamond.

    The theory of the Treatise proposes such ferromagnetically ordered environments of the liquid diamond, higher density fermionic sp3 carbon (diamond) liquid, and lower density bosonic solid diamond just as observed experimentally by Eggert and others via their electromagnetic (laser) pressurizing and melting diamond and just as these liquid diamond and solid diamond states possibly exist on Uranus and Neptune for explaining the unusual shifts in the magnetic poles of these planets relative to their geographic poles. This is a great example of a very beautiful consistency of a prior theory to recent experimental data with applications to Uranus and Neptune.

    Reginald B. Little

  • coryy

    ooooooooooooooh! Just like that Doctor Who episode on Planet Midnight! Do they have extonic sunlight, too???? 😉

  • W. Boyer

    The spur to exploration of the New World was the lure of riches. A discovery like “oceans” of diamond may be necessary to finally ignite and fan the flames of spaceflight and development.

  • Mike

    Although interesting, I hope they don’t send a trillion dollar probe to sample it. It would be wise to focus more scientific thought and money here on the Earth and solve some it’s problems, decrease pollution, study and save species, etc (then we can go play in space).

    The rest of the solar system, although mysterious and fascinating is cold, radioactive and dead. There are no beaches (well, maybe some liquid methane lapping at some shore somewhere), no forest, no coral reefs. Nowhere will we find more exotic life and wonders than right here. Even if there are some bacteria-like organisms living in areas under the ice on Europa or Enceladus, I doubt they will surpass in crazyness and wonder anything existing here.

    So many social problems plague the Earth and as man and his religions struggle for power and resources and strip the planet down and dirty it’s skies so we can fill malls with stuff, we seem to be looking away from the issues here and dreaming of something else to focus on out there. I really see the human race heading in the direction of Disney’s Wall-E. We are spending billions of dollars on this stuff and great scientific minds are spending their careers studying how fast the wind is on Neptune, or the molecular make-up of pink ice on Pluto. I will just have faith that learning about these things will have some positive application or use here on Earth (besides mining for diamonds to sell to the rich)….and I do and will enjoy the info…I would just love to see more scientist get together and figure out how to clean up the Pacific plastic patch…find ways to decrease soots and particulate pollution…

  • Brian Schmidt

    Mike, you’re arguing for spending resources on human needs instead of basic science. I see no point in repeating the argument for spending some money on science instead – I could parrot that side, you could parrot yours. It’s been done to death.

    I’ll just mention that you bring up environmental issues – the greenhouse effect was better understood on Venus before it was applied to Earth (the modern version, anyway). There is a relationship and application of basic science to human needs.

  • Sundance

    Nicely said Brian, but there’s another point; Mike, if the funding was available researchers would spend more effort solving pollution problems, etc. Scientists have to buy food and clothing too, just like everyone else, and if there was more money available for jobs in human needs there’d be more people working on it. You’re “blaming” scientists for having the wrong priorities. you should be criticising governments and companies instead. They spend billions every day on destructive applications, then quibble about technologies to cure diseases or clean up pollution.

  • Captain Potato

    Funny if the economy was turned around with diamonds from outer space! Never mind those conflict diamonds in Africa.

  • charmaine

    “A huge ocean of liquid diamond in the right place could deflect or tilt the magnetic field out of alignment with the rotation of the planet”. So, what would be the next action?

  • Wil

    Diamond oceans on/in Uranus and Neptune? I thought it took enormously high temperatures and pressures to keep diamond in a continuous liquid state.

    Aren’t the temperatures on Uranus and Neptune fairly close to absolute zero?

    Am I missing something?

  • GW

    Wil, I was about to ask the same thing.
    How does that all work?

  • marty

    Wil and GW – good question. unless maybe they are theorizing that these diamond oceans are under the mantle an underground diamond ocean? something close to the planet’s core? i read it twice and came up with the same question.

    Ha ha – i cant wait to see if some schmuck points to this and says “see, global warming IS real”.

  • Aaron

    Wil and GW,

    First, the mean upper atmosphere temperatures of both planets are around 53-55 kelvins, which is nowhere near absolute zero (zero kelvins), and it only get hotter as you descend!

    Second, these planets are nothing like Earth, which has a fairly well defined gaseous atmosphere terminating at a very well defined solid crust floating on top of a mushy, semi-molten mantle surrounding a liquid outer and solid inner metallic core. Instead, Uranus and Neptune are composed mostly of gases (as opposed to silicates, or rock, like Earth). As one descends through their gaseous atmospheres, one never lands on a solid surface! Instead, the pressure and temperature rise dramatically to orders of millions of atmospheres and thousands of kelvins–perfect conditions for creating oceans of diamond. In fact, in such conditions, the boundary between the liquid and gaseous states of matter vanishes, and we are left with what can only be described as a super-dense fluid (though it may still have solid chunks floating around in it). At their cores, the planets are dense masses of silicates, nickel, and iron–best described as if one were to put Earth into a pressure cooker.

    I hope that this clears things up–if you have any more questions, Google them.


    You are striking a nerve, my friend. First, I am unaware of any space probe that has ever cost a trillion dollars (and if NASA had even a thousandth of that budget, it would be pretty amazing). Second, why must all scientific resources be devoted to “practical” endeavors? You would quickly find that by forcing us to fix your problems, fewer and fewer able minded people would go into science at all. Why? Because in many cases it is the discovery of new knowledge and the development of new understanding that excites our passions and draws us into the investigation of Nature to begin with! If someone told me that if I wanted to be a scientist, then I would only be allowed to clean up pollution, I would pursue my passions in art and music instead. In reality, I chose to study mathematics and physics—not to save the world, but to explore the Universe. Can you not appreciate learning how everything around you (and everything of which you are a part) works? We are, after all, as Carl Sagan most eloquently put it, “a way for the Cosmos to know itself.”

    And if you truly believe that the solar system beyond Earth is “cold, radioactive and dead,” then you really ought to get out and see it, for you are terribly mistaken.

  • marty

    thanks aaron.

  • Mitch

    I’m all for exploring however I think that we should be investing in new technologies in order to bring down costs. a good for instance would be the amount of money used for SETA….in the course of our own evolution radio is a passing fad as it would or might be for alien cultures. While it would be astounding to finally know that someone out there is using a radio it would not really help us contact an alien race in the long run.
    I’m sure that there are lasers whose colors are not in nature that we might look for as well as use them ourselves, preferably a good distance from earth, besides riches being a reason to explore so is conquest.
    The amount that we spend on telescopes might be better invested in developing new optical systems, in the future backyard telescopes may have the potential to rival the Hubble’s. We should also be exploring the development of personal self contained habitats that you could use as a home on earth whether on land or sea, drop on the moon, Venus, or Io, that would need only slight tweaking to make it sustainable wherever you might send it.
    And, while this may be in conflict with my original statement, why are we even contemplating sending a tin can with a few people to Mars? If we’re going to go to the time and effort to do this let’s at least look at doing it right, and creating a sub or carrier sized vehicle that mankind can be proud of.
    btw isn’t Jupiter a gas giant also? How can we see impact scars on the planet if it’s a gas giant?

  • Proper Gander

    To everyone wondering about the monetary value of these diamonds, you can probably forget it; it would be cheaper to make them here on earth than to build a spacecraft capable to accelerating to Uranus and recovering a significant amount of diamond (if you could even come up with a workable method for that very difficult problem), accelerate with cargo out of Uranus’s gravity well, and then return it to Earth. You’d never come close to recovering your investment, even if the addition of several tons of diamond into the supply chain didn’t severely depress market prices.

  • Mitch

    Diamonds aren’t that valuable. The market is controlled, the value is artificial. If half the mined diamonds were released in the free market the value would tumble and they’d be worth little. We will find new materials on other planets that will be worth more. BTW, we could finance the Mars expedition if the government would auction off a small portion of the rocks that were returned from the moon on previous expeditions. I’d sure buy one if I could afford it. After our tax dollars paid for bringing them back the first thing the government did was make it illegal for citizens to own one……

  • Aaron

    Proper Gander, Mitch,

    I am glad that you raised the point about the diamonds. Mining those things–now -that- would be a waste of money!

    As for Jupiter’s impact scars, imagine that you have a puddle of clear water with a layer of sediment below. Now throw a rock into that puddle as fast as you can. This will disturb the sediment and muddy up the water, right? Now wait a while–what happens? The sediment re-settles and the water is once again clear.

    The same idea, perturbing a stable equilibrium, applies to Jupiter. First note that although the planet is indeed a “gas giant,” it is truly not all that gaseous. Like Uranus and Neptune, as one descends through the Jovian atmosphere, the pressure and temperature rise dramatically and one would experience a gradual change from gas to liquid. However, unlike Uranus and Neptune, Jupiter is mostly hydrogen, and so beyond the gas-liquid layer, one would find a thick mantle of dense metallic hydrogen, as opposed to a layer of liquid diamond (carbon). Plunging a comet into this would upset the natural state and change the physical system. As a consequence, the perturbed region might not scatter and reflect the usual wavelengths of visible light that we see bouncing off of Jupiter’s cloud bands. Instead, the region, in this perturbed state, might absorb all visible wavelengths, and thus appear to be a black spot. Over time, given the ability of a fluid to flow, the natural equilibrium will reestablish itself, the normal scattering will resume, and the spot will disappear.

    I hope that this answers your question!

  • lol singer

    Wow thats so amazing. But how can it be true when Neptun eis so cold and diamonds is made by heat! LOL thats awsome!

  • woof

    I’m always surprised when people talk about how we should put less money towards space research and more to human needs… as though our lives and needs haven’t been immeasurably improved by products of NASA’s research. Medicine alone owes a huge debt to NASA research. Many massive advances in prosthetics and the pacemaker, dialysis, insulin pumps for diabetics, and many more are entirely based on NASA technology. Look up “NASA spinoffs” and you’ll see a small selection of how many human needs have been met by the work done to get us into space.

  • Planet Neptune

    Im sure in the future billions of dollars will be made from the mineral wealth of the solar system.

  • Koolbeanz



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