Is Jupiter Dissolving Its Rocky Core?

sciencehabit writes "Jupiter is the victim of its own success. Sophisticated new calculations indicate that our solar system's largest planet, which weighs more than twice as much as all of the others put together, has destroyed part of its central core. The culprit is the very hydrogen and helium that made Jupiter a gas giant, when the core's gravity attracted these elements as the planet formed. The finding suggests that the most massive extrasolar planets have no cores at all."

Comments

Ho Hum

[kodiaktau]

Interesting thing about that core, on Earth it helps to create stability in our rotation and it also helps to keep our atmosphere in tact - keeping water in so life can continue. Would be interesting to see some kind of drilling or other process to validate the assertion on other planets. Alas our current US government has sought to sink our space program so it will need to wait for another day.

Re:Ho Hum

[Waffle Iron]

Alas our current US government has sought to sink our space program so it will need to wait for another day.

You mean when they cancelled shuttle-derived boondoggle money pits?

That's actually the best way to *increase* the resources available to do real the planetary science you're talking about.

Re:Ho Hum

[LordLimecat]

and it also helps to keep our atmosphere in tact

Id never heard of this, can you explain? I had always understood that to be simply because of gravity. I knew the core was supposed to be the cause of our magnetosphere, but thats it.

Re:Ho Hum

[rahvin112]

We know A LOT about the cores of the planets in the solar system from extensive study (including molten, material and other stuff that can be determined from external study). It appears you are talking about examining extrasolar planets. We don't have the capability, and it's doubtful we will, at least in our lifetime. Voyager1 just left the solar system and it's moving at ~35k MPH and it was launched in the 70's, most of the people that designed it are retired or dead and Voyager1 will be dead long before it reaches any other star.

Re:Ho Hum

[Anonymous Coward]

The Magnetosphere helps keep solar winds from stripping our atmosphere away from us.

Re:Ho Hum

[boddhisatva]

What maintains our atmosphere is the magnetic field generated by the liquid mantle rotating around the core. The magnetic field deflects the solar wind which would blow it off. It's thought by some that Mars lost it's atmosphere and surface water when the liquid mantle cooled and solidified. Mars has no magnetic field.

Re:Ho Hum

[John_Booty]

I knew the core was supposed to be the cause of our magnetosphere

That's a large part of the answer right there! The magnetosphere acts as a shield to keep a lot of harmful particles from the solar wind away, things which would work to strip away the atmosphere. Mars is an example of what can happen to planets that lack this. (Obviously, Mars' lower gravity works against it in this regard as well)

http://science.nasa.gov/science-news/science-at-nasa/2001/ast31jan_1/

Re:Ho Hum

[Anonymous Coward]

OtakuBooty.com [otakubooty.com]: Smart, funny, sexy nerds.

Pick two.

Re:Ho Hum

[Anonymous Coward]

I'm glad to see the shuttle no longer leeching the life out of NASA, but you have to know the cuts go well beyond that. It's not like ditching the shuttle actually freed up more funds for NASA. Bankers need their bonuses far more than we need to do basic science, after all.

Re:Ho Hum

[Anonymous Coward]

I submit that "funny, sexy, nerd" is an oxymoron. Smart and funny, or smart and sexy, while rare, are at least logically conceivable.

Re:Ho Hum

[Grishnakh]

It's not just wars that we need to pay for; we also need to give giant no-strings-attached bailouts to mismanaged "too big to fail" financial companies so they can screw around with our economy with impunity, and not worry about any government regulators telling them how to do anything.

Also, don't forget the all-important War on Drugs that we need to pay for, so that we can send millions of non-violent people to privately-owned prisons and increase the profit margins of corporations like Wackenhut and CCA.

Re:Ho Hum

[Anonymous Coward]

"That's actually the best way to *increase* the resources available to do real the planetary science you're talking about."

Well, let me know when the first spaceship launched by Virgin starts off towards another planet then.

Re:Ho Hum

[Anonymous Coward]

Which brings up the question: Which will happen first? Earth's core cooling to the point where we lose our atmosphere, or the Sun running out of fuel to the point where Earth can no longer sustain life (as we like it)?

Re:Ho Hum

[MightyMartian]

Then how does Venus, which has almost no magnetic field manage to retain a very dense atmosphere?

Re:Ho Hum

[JATMON]

Which brings up the question: Which will happen first? Earth's core cooling to the point where we lose our atmosphere, or the Sun running out of fuel to the point where Earth can no longer sustain life (as we like it)?

The correct answer is neither. Both of those are billions of years in the future. You forgot about a more immediate threat to the planet. Unless something drastic happens, the Human race will have made the earth devoid of life long before that. And even if we don't f' the planet up beyond all fixing, it wont matter because humans will either be extinct or will have colonized the galaxy by then.

Re:Ho Hum

[wierd_w]

Look at the composition.

Venus's atmosphere is very low in certain molecules.
Nitrogen.
Elemental oxygen.
Water vapor
Et al.

What it is high in, are comparatively dense gasses.
Sulfuric acid
Carbon dioxide
Etc.

The solar wind is highly energetic, but is comprised of small atomic mass particles. They lack the kinetic energy to strip away very heavy gasses with strong intermolecular forces. Water, while having strong intermolecular forces, is a very light molecule, and the high energy particles have sufficient energy to break the single covalent bonds that hold it together. This means the cosmic wind rips it apart, and then scours it out into space. Sulfuric acid and cabron dioxide, on the other hand, are very heavy, gravitate deeper into the gravity well, and in the case of co2, have double covalent bonds that are quite powerful. The solar wind doesn't have enough oomph to rip it apart, and the molecules are too heavy to easily blow away.

Mar's armosphere is actually sabotaged by a weak and incomplete magnetic field. It has many small and weak diploles extending from the surface. Under the influence of the solar wind, this actually pinches off large chunks of atmosphere during heavy flares from the sun. This is why mars has such a pronounced atmospheric loss, compared to venus, which doesn't have any discernable mgnetic field at all. If you note, the atmosphere mars does have is comprised of what? Co2.

Re:Ho Hum

[Anonymous Coward]

Wars are good. They are the quickest form of population control. They also have a lot of science value also. How else are we going to test all the latest weapons technologies that our scientists and engineers have created.

Re:Ho Hum

[Shotgun]

"too big to fail" financial companies was so last term. The new fashionable bailout target is "green companies".

Re:Ho Hum

[Dishevel]

The heavy carbon dioxide that makes up most of Venus's atmosphere tends to stick around. Though Venus is losing much of its Hydrogen and Helium to the solar winds.

Re:Ho Hum

[Waffle Iron]

Well, let me know when the first spaceship launched by Virgin starts off towards another planet then.

That toy for the rich is just as much of a silly stunt as NASA's cancelled rockets (only a lot cheaper).

For decades, commercial off-the-shelf rockets have been available to launch serious science payloads throughout the solar system. New commercial ventures are bringing lower-cost versions of the same as we speak. At this point, NASA shouldn't be spending a single dime on launch technology. Any such spending only detracts from their scientific goals.

Re:Ho Hum

[Missing.Matter]

Venus's ionosphere creates an induced magnetosphere. It's not as good as the one we have, but it does enough to keep the entire atmosphere from being blown away.

Re:Ho Hum

[FreeUser]

"too big to fail" financial companies was so last term. The new fashionable bailout target is "green companies".

No no no, that was yesterday's meme. We have come full circle and returned to calling them "job creators."

Re:Ho Hum

[Anonymous Coward]

Venus actually has a similar amount of nitrogen in its atmosphere (measured as a partial pressure) to the Earth, despite molecular nitrogen being the lightest of the common atmospheric gases.

Re:Ho Hum

[Overzeetop]

Buzzkill

Re:Ho Hum

[njvack]

Mar's

Never has an apostrophe made me so sad.

Re:Ho Hum

[fahrbot-bot]

Mar's

Never has an apostrophe made me so sad.

See post after yours:

Venus's ionosphere

Re:Ho Hum

[Thiez]

Neither. As the sun gets older, it gets brighter (according to wikipedia, about an 10% increase in luminosity every billion years). At some point there will be no more liquid water available because the surface of our planet is too hot. This will happen long before the sun turns into an actual red giant, which in turn will happen long before it runs out of fuel.

Re:Ho Hum

[wierd_w]

Total mass, yes. Percentage wise, not even close.

The vast majority of interaction will be with the resilient and heavy co2 molecule, and not the much ligher n2 molecule.

That does not mean venus is not losing nitrogen to solar wind, it means the heavy percentage of c02 greatly reduces rate of loss.

Re:Ho Hum

[ulzeraj]

This document explains a bit about the process: http://www.vanderbilt.edu/AnS/physics/astrocourses/AST101/readings/water_on_venus.html. It cites the abnormal ratio between hydrogen and deuterium compared to earth leading to the conclusion that the planet lost most of its hydrogen to solar wind particles.

Re:Ho Hum

[wierd_w]

Ahhh.. Slashdot. Where commenting about a misplaced apostrophe in an otherwise seemingly salient post is somehow more important than the subject the poster was writing about.

It doesn't matter that they were actually right or not. They dared to misuse an apostrophe. That makes them wrong. ;)

We won't even get into what happens when someone misuses a coma, or uses the wrong phoneme... there might be children present!

Re:Ho Hum

[HermMunster]

OK, so it is. I dare you to do something about it.

Re:Ho Hum

[baegucb]

"For decades, commercial off-the-shelf rockets have been available to launch serious science payloads throughout the solar system."

silly citation needed meme inserted here

Re:Ho Hum

[TangoMargarine]

Wow, you just took a theoretical science question and totally twisted it into a sociopolitical one that the grandparent wasn't asking for at all. Interpreting your logic literally, either the core cooling and sun fuel running out will occur simultaneously, or never.

PS: Yes, maybe everything in your post is technically true.

Re:Ho Hum

[Waffle Iron]

Do the names Titan, Delta, Ariane, Atlas, etc. ring a bell?

Re:Ho Hum

[Anonymous Coward]

This is incorrect. The solar wind is composed primarily of protons with energies of about 1 keV. The bond energy in carbon dioxide is about 11 eV. A 1 keV proton has plenty of energy to split CO2, H2SO4, and pretty much any molecule.

Re:Ho Hum

[Anonymous Coward]

There is no evidence that the earth will be devoid of life. People and animals maybe, Plants tend to like the direction the climate is moving. Stop being so selfish.

Re:Ho Hum

[ErikZ]

NASA does basic science?

Your bar is set...ridiculously high.

Re:Ho Hum

[Khyber]

Prolly not, I hear Alzheimer's in 5-digit UIDs is rising.

Re:Ho Hum

[Khyber]

"They lack the kinetic energy to strip away very heavy gasses with strong intermolecular forces."

But they possess more than enough energy potential to still split apart heavier molecules into lighter constituents.

UV radiation alone can do this, especially in the UVC range (which our atmosphere happens to filter out due to water.)

Re:Ho Hum

[Black Gold Alchemist]

Sort of MARred the post for you?

Re:Ho Hum

[Anonymous Coward]

It doesn't matter that they were actually right or not. They dared to misuse an apostrophe. That makes them wrong. ;)

I shouldn't need to explain this, but not everyone here is an astrophysicist. We don't all know a lot about space and other planets but we do know how to read and write English.

The conclusion should be obvious but if it isn't, grammar is something that the average person has sufficient knowledge to claim knowledge and expertise, criticizing the science of the post requires specialist knowledge about space so is ignored. [If you don't know something, shift the conversation to something you do]

Re:Ho Hum

[sFurbo]

The earth's core isn't cooling, AFAIK. Nuclear decay keeps it nice and warm. Of course, that will end gradually, but when it hasn't done so yet, it probably won't be a problem until the sun becomes a red giant.

Re:Ho Hum

[Anonymous Coward]

It's actually a compliment.

Re:Ho Hum

[mcgrew]

You should sic Bob on him. It's probably not an accurate appraisal, but I always question the education, and maybe even intelligence, of anyone who can't use that simple punctuation mark properly.

What's worse, I see it more and more. Doesn't anyone read books these days?

Re:Ho Hum

[mcgrew]

They dared to misuse an apostrophe. That makes them wrong. ;)

No, it marks them as uneducated and likely not very intelligent. Same with phoneme misuse. I can't take someone who writes like a ten year old seriously.

Re:Ho Hum

[Anonymous Coward]

Stop it already. Global warming will not exterminate humans, let alone any other life forms. Even if we detonated every nuclear power plant on earth, life would go on, in some form.

You, and people like you, are grossly overestimating how hard it would be to kill all forms of life on the planet. The more complex life forms are easier to kill, but even in the worst case scenario it is implausible that no small group of humans would survive anywhere on the planet.

Re:Ho Hum

[RockDoctor]

What maintains our atmosphere is the magnetic field generated by the liquid mantle rotating around the core.

Liquid outer core stirred up by thermal and magnetic turbulence and a solid inner core. The mantle is more-or-less solid.

Mars has no magnetic field.

Now ; it probably had one for a short period early in it's history ; there is some evidence of "magnetic stripes" (and by implication, something resembling sea-floor spreading ?) in the region to the south of the Tharsis volcanoes.(IIRC)

Re:Ho Hum

[Rich0]

At this point, NASA shouldn't be spending a single dime on launch technology. Any such spending only detracts from their scientific goals.

Well, there is no harm in them spending money on true blue-sky research - the sort of thing that is less likely to get done by a commercial entity. Of course, you can do that with small rockets/etc - you don't need to build huge rockets to test a concept. If they figure out how to get payloads to orbit for $1M or something then maybe they can build a proof-of-concept, though at that price I suspect that private industry would be more than willing to test it out unproven.

However, I agree that there is no value in having NASA churn out current-technology launch vehicles - it is far cheaper to do that elsewhere.

Re:Ho Hum

[Anonymous Coward]

The planet's: Mercury, Venu, Earth, Mar, Jupiter, Saturn, Uranu, Neptune.

Re:Ho Hum

[Coren22]

I read on my Nook, with the unfortunate conclusion that eBook vendors don't employ editors. It is quite sad when you see OCR errors in a commercial book that even a spell check run through would have caught.

Diamonds are Forever

[djl4570]

Hey, it has to have a core. Diamonds are forever.

Re:Diamonds are Forever

[Anonymous Coward]

That is actually a misnomer. Diamons, like everything else, decays given enough time. Entropy wins.

Re:Diamonds are Forever

[Trepidity]

Clearly DeBeers needs to hire you to lead their next ad campaign, "Diamonds are quite long-lasting relative to other materials, though they will eventually decay".

Re:Diamonds are Forever

[Anonymous Coward]

Entropy, bitches.

Re:Diamonds are Forever

[Grishnakh]

I'm not so sure about everything decaying over time. I thought everything decayed over time to its most-stable state; once a material was in that state, then theoretically it shouldn't decay any more, right?

The most-stable state for carbon is graphite I believe. So diamonds will eventually decay into pencil lead. But once they've turned into graphite, I don't think they'll decay any more.

Re:Diamonds are Forever

[Anonymous Coward]

Bitches meme, bitches.

(one that many of us loathe very very much.)

Re:Diamonds are Forever

[marcosdumay]

In a long time, it will decay into iron.

Unless the Big Rip comes earlier, then it will be no more.

Re:Diamonds are Forever

[Migraineman]

To expand this a little -

Through fusion, lighter elements like hydrogen and lithium may be combined (nuclear). This process will provide a net energy output up to "iron."

Through fission, heavier elements may be disassociated (nuclear). This process will provide net energy output down to "iron."

When all you have left is iron, making something else via nuclear methods requires the addition of energy. Thus, "everything decays to iron" represents a lowest energy state from a nuclear perspective. But don't worry, the heat death of the universe won't happen for a long while.

Re:Diamonds are Forever

[KingMotley]

I propose "Diamonds may not last forever, but it is likely it will last longer than your relationship to the person you are giving one to" be their new slogan.

Re:Diamonds are Forever

[cowboy76Spain]

Entropy always increases.

A diamond is a very ordered configuration which will become progressively more disordered. Its configuration may mean that the reactions that alter it (with the oxygen of the air, by example, or even a dislocation of carbon atoms inside the structure) work very slowly, but in the end when these happen there is no turning back.

So, little by little the diamond is decaying into carbon, CO2, etc.

Re:Diamonds are Forever

[Grishnakh]

Of course, this decay of diamonds doesn't have to be slow; a blow-torch will speed it up quite a bit:
http://www.popsci.com/diy/article/2009-08/burn-diamonds-torch-and-liquid-oxygen

Note that cubic zirconia is immune to blow-torches, plus it costs less and looks better.

Re:Diamonds are Forever

[Anonymous Coward]

After about ~10e100 years the universe consists of thermal noise. Everything else has ceased to exists.

Re:Diamonds are Forever

[sFurbo]

Yes, but are there wars over cubic zirconia? If I give a stone as a symbol of the love I have for someone, by god, I demand to have lifes on my consience! Besides, there isn't a monopoly artificially keeping up the price of cubic zirconia, so it isn't an effective, yet publically accepted, way to show off my wealth.

Re:Diamonds are Forever

[meglon]

You really opened up a can of worms with that. In the responses I see a confusing mixture of the ideas of entropy, disorder and chaos, stellar fusion, and universal heat death, and apparently some people who think these are the same thing? Entropy alone is a huge confusing subject, but to conflate it with these others... well.. that's a whole new ball game.

Re:Diamonds are Forever

[Grishnakh]

You're right that there's no monopoly artificially keeping up the price of CZ, but you can always show off your wealth with stones that are actually rare, and don't need a monopoly to keep their prices up artificially. I believe emeralds are a good example of this. However, I've never heard of any wars over them (nor have I heard the term "conflict emeralds"), so you would be missing out on that by buying them. This is probably why you don't hear much about Emeralds; American women want overpriced stones where people have been killed unjustly to acquire them, and have someone's blood on them, so with stones like emeralds and rubies that don't have much blood on them, they're simply not interested.

Yeah get rid of that old core

[youn]

get at least a quad core... time for an upgrade haha :)

Monoliths

[OakDragon]

Just need to toss in several hundred thousand black monoliths, and we'll have a new star in the firmament.

Re:Monoliths

[Anonymous Coward]

Fucking monoliths, how do they work?

Re:Monoliths

[swilly]

Sufficiently advanced technology.

Re:Monoliths

[mrmeval]

I believe there is a paper that describes how to trigger a self sustaining fusion reaction in Jupiter's atmosphere. I believe the paper was triggered by 2001 when it came out. I am an ineptly erased slate for anything I experienced prior to 2000 so ...

Re:Monoliths

[Anonymous Coward]

*Touches the black surface carefully. Feels the surface touching back. Draws back the hand. Feels tingling sensations in the head.*

Re:Monoliths

[LoRdTAW]

Have a look here:
http://www.badastronomy.com/bad/misc/jupiter_galileo.html

Apparently Jupiter has 1/80th the necessary mass that is needed to become a star. Even if Jupiter were to combine with Saturn it would still lacks the necessary mass to "ignite".

Weight?

[wisnoskij]

"which weighs more than twice as much as all of the others put together"
I wonder if this guess is still correct. I would assume this weight was appropriated by assuming the planet had a solid core?

Re:Weight?

[pixelpusher220]

Dissolving a solid into a liquid doesn't change it's mass.

Re:Weight?

[spire3661]

You do realize that liquid rock has the exact same mass as solid, right? They aren't saying that this bodies never had cores but rather that the solid core was eroded.

Re:Weight?

[Anonymous Coward]

I would assume that the weight calculations would be made based on the weak gravitational pull upon Jupiter's own moons, as well as the slight pull of Jupiter on other planets, comets and asteroids which have orbits that bring each other closer together and in turn slightly alter trajectories or relative speeds of motion rather than the tried and true "rats do it just like us" observation.

Re:Weight?

[camperdave]

No. It is estimated by the orbits of it's satellites, using Kepler's laws. If you know the period, eccentricity, and size of a satellite's orbit, you can work out the mass of the object that the satellite is orbitting. It has nothing to do with how much of that object is solid.

Re:Weight?

[dougisfunny]

Next thing you'll tell me is that a pound of feathers weighs as much of a pound of bricks!

Re:Weight?

[nedlohs]

Nope.

We "weigh" planets by observing the gravitational force acting on a space craft (whose mass we know) we send close to them. Or by measuring the mass of something else (say by observing a space craft near it) and then observing how it interacts gravitationaly with the planet in question.

You can also do some math with pulsar timings to see periodic errors due to the barycenter of the solar system not being exactly where you thought - which will also give you the planetary masses (well the planet plus the moons,etc). But I only saw a paper on it I didn't understand it or anything crazy like that.

Re:Weight?

[camperdave]

I don't know about bricks and feathers, but a pound of sand weighs more than a pound of gold, even though an ounce of sand weighs less than an ounce of gold. Stupid customary units.

Re:Weight?

[Baloroth]

Yeah, but it does wonders for it's weight.

Also, you can't really use the term "weight" for a planetary core. Since the core is at the center of gravity, it has no weight whatsoever. Well, except for towards the Sun, I suppose. Not sure if TFS would be correct or not about the weight in that respect.

Re:Weight?

[Anonymous Coward]

The weight around the sun is still zero because of it's motion. An astronaut on the ISS stanning on a scale will show zero. If Jupiter stopped in it's orbit, now you have weight.

Re:Weight?

[Anonymous Coward]

You do realize that liquid rock has the exact same mass as solid, right?

That's mostly correct, but as heat is a form of energy and E=mc^2, a rock changed into liquid state would mean that it weighs oh-so-slightly more. For some napkin calculations: the specific heat of iron (at 273 K) is 0.45 J/(K g) meaning that if we had a thousand tons of iron (1E9 g) and increased the temperature 1000 K then the increase of mass would be: 0.45*1E9*1000/(3E8)^2 = 5E-3 g. All that mass and energy for a full 5 milligrams, which is why it's mostly negligible

Disclaimer: I know that the specific heat changes (quite a bit) with temperature but I wanted to keep the example simple.

Re:Weight?

[v1]

weight is really easy to figure out, or what I'm assuming you're talking about, mass, since it produces the easily observable effect of gravity

Remember that "weight" is the effect of gravitational attraction between separate bodies that possess mass. You can't talk about "weight" unless you're referring to at least two objects. (usually with great differences in mass, such as a planet and an object on said planet)

Re:Weight?

[GungaDan]

That is totally not what I meant by "go pound sand."

Re:Weight?

[ILMTitan]

Unless it is big enough to deflect the planet it is orbiting (Pluto/Chiron), the mass of the satellite does not matter. All that matter is the particulars of its orbit.

Re:Weight?

[synapse7]

Besides that, assuming Earth was the reference is it possible for something to be twice the weight of all other planets on Earth?

Re:Weight?

[Pope]

Go (get a) pound (of) sand?

Re:Weight?

[aintnostranger]

No. What's estimated is mass. not weight.

Re:Weight?

[wisnoskij]

Did not read the original article, but I would assume that it likely changed it density as well.
Meaning that lots of liquid core could have been pushed to the surface making the planet appear bigger and more massive from the outside.

Re:Weight?

[Anonymous Coward]

You and the original OP need are idiots. Please castrate yourself so as not t infect the already polluted genepool.

Re:Weight?

[Anonymous Coward]

Next thing you'll tell me is that a pound of feathers weighs as much of a pound of bricks!

If they are in different gravity field, then, yes, they might.

Re:Weight?

[pclminion]

Given that a pound is a unit of weight, no, they would not.

Re:Weight?

[lennier]

> GO POUND SAND

The pound sand doesn't appear to have an entrance.

Re:Weight?

[Anonymous Coward]

I am an American. I know what mass is. Maybe you should learn to construct proper sentences before calling others stupid.

Re:Weight?

[Grishnakh]

I'm an American too, and I'd guess maybe 10% of the population here knows what mass is. The ones who watch The Kardashians and Jerry Springer, however, don't.

There's nothing wrong with my sentences; maybe you should learn to not be an asshole.

Re:Weight?

[Anonymous Coward]

Pound sand have entrances for not so well endowed.

Re:Weight?

[Anonymous Coward]

Did not read the original article, but I would assume that it likely changed it density as well.
Meaning that lots of liquid core could have been pushed to the surface making the planet appear bigger and more massive from the outside.

Why? I mean, if we haven't actually observed the core yet (we've only inferred its existence in some form), how would a solid or liquid core alter Jupiter's appearance when all we see is the gas at the top? We can measure Jupiter's mass and volume (and its average density as a result) and make good estimates as to the composition of gases it has up top, but when talking about gravitational forces and center of mass our observations won't change if at the center there's a big ball of lead or an ocean of water (that occupies 11 times more space than the lead) because the gas layer goes much higher up and prevents us from peaking onto the surface, assuming there's a surface to be seen.

Re:Weight?

[HiThere]

Probably not. The density of the core decreases, but the density remains pretty high. (The pressure is high enough to liquify hydrogen at a reasonable temperature.) And while the core has now disappeared, there is a larger volume of denser liquid.

Besides, what you see when you look at a gas giant is the atmosphere. That's not going to change measurably.

Re:Weight?

[Anonymous Coward]

...because the Bible told me so...

Re:Weight?

[Prof.Phreak]

You do realize that liquid rock has the exact same mass as solid, right?

To be perfectly technical, no it does not. Molecular bonds and heat have mass too...

Re:Weight?

[Tim C]

I hate to weigh in on the side of a somewhat dickish AC, but:

readers who actually have some science education should be infer to understand what they really mean

is not well-formed.

Re:Weight?

[Anonymous Coward]

TAKE SAND

Re:Weight?

[nedlohs]

Yeah you'd have to be an idiot (such as myself) to not see the obvious:

m1 is the mass of the planet. m2 is the mass of the satellite.
F = G.m1.m2/r^2 * Thanks Newton.
F = m2.a * Thanks Newton again

m2.a = G.m1.m2/r^2
a = G.m1/r^2
m1 = a.r^2/G

Since we know G and the orbit of the satellite gives us r and a we can determine m1. Of course since the orbit isn't going to be a perfect circle there's some details I can't be bothered to think about :)

Re:Weight?

[Grishnakh]

Unlike the dickish AC, you actually pointed out the problem. In my rush, I left out the words "able to".

Re:Weight?

[LWATCDR]

That and under that tempiture and pressure we are talking about a liquide very unlike any liquide we normally deal with.

Planet or corporation?

[Anonymous Coward]

It's been known for a long time most giant corporations are hollow at their core.

did it ever have a core?

[Trepidity]

As far as I know, that question was still open to at least some debate. It's hypothesized that there should be a solid core based on the mineral composition and some simulations, but I don't believe there's any direct evidence of it, at least until the mission (mentioned in the article) to measure its gravitational field with an orbiting probe reaches it.

Re:did it ever have a core?

[CanHasDIY]

As far as I know, that question was still open to at least some debate. It's hypothesized that there should be a solid core based on the mineral composition and some simulations, but I don't believe there's any direct evidence of it, at least until the mission (mentioned in the article) to measure its gravitational field with an orbiting probe reaches it.

Wouldn't that apply to Earth's core as well? I mean, as far as I'm aware no one has ever drilled all the way to the center of the planet, so what evidence (beyond hypothesis) is there that Earth's core is what we think it is?

Re:did it ever have a core?

[Trepidity]

There's some evidence beyond only mineral composition for the earth's core, mostly from seismic data; the discontinuities observed in seismic wave travel put constraints on what has to be the case at different layers. At least, it's more data than we have about the interior of Jupiter, which afaik is entirely based on mineral composition and modeling.

Re:did it ever have a core?

[Anonymous Coward]

two words - remote sensing.
ther are ways to measure stuff wihtout actualy needing to have a piece of it in your hand.

Re:did it ever have a core?

[vlm]

There's some evidence beyond only mineral composition for the earth's core, mostly from seismic data; the discontinuities observed in seismic wave travel put constraints on what has to be the case at different layers. At least, it's more data than we have about the interior of Jupiter, which afaik is entirely based on mineral composition and modeling.

Some data comes from detailed magnetic field monitoring, makes sense since it seems to be the cause of the earths magnetic field.

http://en.wikipedia.org/wiki/Inner_core#Dynamics

Re:did it ever have a core?

[camperdave]

They have "drilled down" to the Earth's core with sound waves. They use seismic charges to bounce sound waves off the core.

Re:did it ever have a core?

[Anonymous Coward]

You could have googled for the answer instead of displaying your foolishness here but now you just look like a total loser.

Re:did it ever have a core?

[avandesande]

Isn't it theorized by some that the pressure is high enough in Jupiter that the hydrogen is metallic? Does anyone really understand the metallurgy of metallic hydrogen?

Re:did it ever have a core?

[The Grim Reefer]

I'm by no means up on the latest theory about what is at the core, but I thought that it's been some time since it was believed to be a solid "rock" as we would think of it. The last I heard, it was mostly likely metallic hydrogen. Theoretically (or maybe it's fact now) metallic hydrogen should be a high temperature superconductor. If true, this could also explain Jupiter's massive magnetic field.

Re:did it ever have a core?

[Anonymous Coward]

So you think the only way to examine the inside of the human body is to cut into it? Don't be a dumbshit.

Re:did it ever have a core?

[bryan1945]

At least someone else realized that this is just all math predictions. TFA even says that we can't experimentally model the core of Jupiter. Was it Galileo that dropped into Jupiter? For a whole few hundred miles? Sorry boys, but you're playing with math here, not with anything even approaching real known conditions on Jupiter.

Weight vs Mass

[Anonymous Coward]

Come on Slashdot, we're supposed to be more science-oriented than average. Weight doesn't make sense for a planet, since you have no well-defined gravity reference. It would have twice as much mass as the others put together. I am disappointed.

Re:Weight vs Mass

[Anonymous Coward]

Sure it does, there's this nice reference object at the center of the solar system.

Which weighs twice as much?

[Anonymous Coward]

I think you mean has twice the mass.

core is icey hot?

[Nyder]

...central core made of iron, rock, and ice. .... The temperature there is approximately 16,000 kelvin—hotter than the surface of our sun....

Okay, maybe ice means something else on Jupiter. Can someone explain how Jupiter's core can have ice that doesn't melt?

Re:core is icey hot?

[ZombieBraintrust]

Ice doesn't mean cold water. Ice is solid water. Water is liquid, solid, or gass depending on temperature and pressure. There is alot of pressure at the core of Jupiter.

Re:core is icey hot?

[polymeris]

High pressure from all that mass, possibly? Just speculating here.

Re:core is icey hot?

[Baloroth]

...central core made of iron, rock, and ice. .... The temperature there is approximately 16,000 kelvin—hotter than the surface of our sun....

Okay, maybe ice means something else on Jupiter. Can someone explain how Jupiter's core can have ice that doesn't melt?

Pressure.

Re:core is icey hot?

[Obfuscant]

There is alot of pressure at the core of Jupiter.

That's nothing compared to being the core of Saturn. You scrub and scrub and scrub and nothing gets rid of those rings, and then Neptune comes home and wants his dinner and doesn't understand that you've been working hard all day. 'Get me a beer!' he hollers as he plops his ass down into the big comfy chair and starts watching Wheel of Fortune.

I tell 'ya, being the core of a planet ain't all wine and roses, I tell 'ya.

Re:core is icey hot?

[Anonymous Coward]

You beat me. I was looking for that chart. It's pretty clear that above 1 million atmospheres (the 100GPa line), water is going to be usually solid. The article lists the core pressures of Jupiter at about 40 million atmospheres, a little into the 'consistently Ice 11' part of the chart. The chart doesn't go far enough in temperature to show exactly what state to expect at 16000K, but from the slopes in the first 750K (shown) it looks like it'll either be clearly ice at that pressure or near another melting line.

Re:core is icey hot?

[mister_playboy]

it'll either be clearly ice at that pressure or near another melting line.

You do remember that solid water is less dense than liquid water, right?

It is possible to melt ice merely by increasing pressure.

Re:core is icey hot?

[mister_playboy]

To correct myself, water in the highest pressure areas of the core would actually be an ice, but in a different phase than the one we are familiar with everyday

http://en.wikipedia.org/wiki/File:Phase_diagram_of_water.svg

It appears even at 10GPa we would actually expect a liquid phase.

Re:core is icey hot?

[Anonymous Coward]

Was that supposed to be funny? It was just dumb.

Re:Who gives a flying fuck?

[Trepidity]

You could just repost a version of that objection for almost any piece of science research without immediate applications...

Re:Who gives a flying fuck?

[DamonHD]

So nothing that cannot be immediately used to make money is of any interest then?

Rgds

Damon

Re:Who gives a flying fuck?

[Anonymous Coward]

Because this is /.

It's information, therefore it must be known to us. I think you'll find OMG! much more to your liking.

Re:Who gives a flying fuck?

[Anonymous Coward]

Who cares about how many galaxies there are in the Universe? We can't do anything about it, we can't get there, we can't use it.

rescue mission to the core?

[miserere nobis]

Oh no! We better drill a hole to the center of Jupiter and explode a nuclear bomb to fix it, because that makes sense!

Re:Who gives a flying fuck?

[Anonymous Coward]

Because a greater understanding of physics allows you to have neat and interesting toys such as computers... (the space race is credited with the invention of the microprocessor)

Re:Who gives a flying fuck?

[Anonymous Coward]

Your mom!

Core disappears == core stops spinning?

[White Flame]

The move "The Core" has ruined me for any article mentioning planetary cores. :-(

Re:Who gives a flying fuck?

[Deflatamouse]

Ummm, we got there. Voyager 1 and 2? Galileo? No we didn't get into the core, but we can send spacecrafts there just fine.

If we know for certain that there is no rocky core, then it would be pointless to build probes to try to reach/hit the core eh?

It wasn't us!

[eyenot]

âZ"We're pretty sure it has nothing to do with our decision to smash a huge plutonium powered space probe into it or with the resulting huge purple 'second spot' caused by the resulting plume, which was so large it was visible to backyard telescopes and in general was a sort of shocking embarrassment to NASA when it occured."

"No, this disintegration now suddenly occuring just a few years after that incident has nothing to do with us. Jupiter was in the middle of killing itself, anyways. It was only a matter of time before this happen."

"JUPITER WAS ASKING FOR IT, I SWEARS T'YA!"

Aliens or not?

[Anonymous Coward]

Termites! Run for your lives!!!

Planetary cores on gas giants

[boddhisatva]

Late in the formation of the solar system it was filled with objects colliding, merging, being blasted apart, etc. The gas giants were rotating around the sun faster. Saturn at one time may have circled at exactly 1/2 the rate of Jupiter. When they came around together, their combined gravity perturbed the orbits of Uranus and Neptune, which are not where they should and may have switched places as #7 & #8. The giants slowed as the result of collisions with and absorbtion of, lots of asteroid type material still bouncing around. Something hit Uranus hard enough to knock it on it's side where it now rotates as opposed to all the other planets. The gas giants may not have rocky cores from birth but a lot of rocky material has dropped in since. We watched a comet plunge into Jupiter just a few years ago. Just another drop in the bucket, but it builds up over time.

Yo Momma Joke

[Anonymous Coward]

Yo momma so fat, her core dissolved!

Re:Yo Momma Joke

[Dogtanian]

Yo momma so fat, her core dissolved!

Hmm... this one's quite good, actually. :-)

Re:Who gives a flying fuck?

[oodaloop]

Exactly. And what good is a newborn baby? Completely useless.

Re:Who gives a flying fuck?

[coinreturn]

So nothing that cannot be immediately used to make money is of any interest then?

Rgds

Damon

No, but there is a limit to what matters to the lives of 99.9999999999% of the people on Earth.

Silica?

[Convector]

What happens to the silica? From my skimming of TFA, it appears that the experiment only involves the dissolution of the MgO component. There should still be gobs of MgSiO3 (or at the very least SiO2, if the MgSiO3 breaks down into its constituent oxides at the high pressures) hanging around down there.

Re:Silica?

[Xerxes314]

According to TFA, the MgSiO3 dissociates into SiO2 and MgO under Jovian core conditions. They don't calculate what happens to the SiO2, but assume that its solubility is similar to the MgO component. So that would mean that the SiO2 also goes into solution in the Jovian core.

Also of interest (at least to me) but not addressed in this paper is what happens to the nickel-iron component of the core. Perhaps they figure Jovians don't have enough to worry about, since they form so far from the center of the protoplanetary disk?

Re:Silica?

[Convector]

That's a good point about the iron. There should be some, but at a far lower abundance than the silicates. Still, we're probably talking a few Earth masses of metal (real, actual metal, not what astrophysicists call metal).

I did notice that they speculated that the SiO2 should also dissolve, but I don't really know how valid that assumption is.

Re:Who gives a flying fuck?

[coinreturn]

Ummm, we got there. Voyager 1 and 2? Galileo? No we didn't get into the core, but we can send spacecrafts there just fine.

If we know for certain that there is no rocky core, then it would be pointless to build probes to try to reach/hit the core eh?

We didn't get anywhere NEAR there (relatively speaking). Yes, we went beyond there, but they would have been vaporized long before they could get "reasonably" close. There is no fucking way we are getting ANYTHING to reach/hit the core.

Re:Who gives a flying fuck?

[viperidaenz]

wars do a lot to further technology. would we have done the research and built the early computers if there were no pesky german codes to break?

Re:Who gives a flying fuck?

[fnj]

Well, "we" didn't get there. "We" haven't gone beyond the far end of a low moon orbit a very few times. And we haven't extended our reach in over 40 years. Spacecraft that we built have gone farther. It seems a distinction worth making to me; maybe it's silly. When man ceases to explore in person, and that day may have arrived permanently, he will be something different, in my mind.

Re:Who gives a flying fuck?

[DamonHD]

So no one should do a PhD to become the world authority on a subject then? No one should try anything new (let's say, for example, a certain chap's musings on the photoelectric effect or relativity)? And by your numbers even spending 0.001 of a single person's time on something not directly productive should be stopped. So let's ban all art and sports (when you've finished off all pure science research), since I have no time for them. And cooking beyond the purely functional, and interior decoration, and sex beyond that strictly necessary for replacement rate childbirth.

And you please certainly stop spending time on /. right now and spare us your narrow-mindedness. Or at least don't post if you have nothing useful to say.

Please accept that just because *you* are not interested does not automatically rob something of value.

(Note that this is not a particular hot topic for me, but it's certainly interesting and I can see a number of intriguing lines of thought running from it, some of which, BTW, may spur practical results.)

Rgds

Damon

Re:Who gives a flying fuck?

[Anonymous Coward]

No, but there is a limit to what matters to the lives of 99.9999999999% of the people on Earth.

Yes, but what about that other .007 person?

Re:Who gives a flying fuck?

[Shotgun]

And if we knew there was a rocky core, it would still be pointless to build probes to try to reach/hit the core.

It's official

[ravenscar]

Jupiter is no longer hard core.

Elementary how to fix it

[tkrotchko]

We'll send special ships to the center of the earth with large hydrogen bombs that will restart the rotation of the core itself.

This is all documented here:
http://en.wikipedia.org/wiki/The_Core

Re:Elementary how to fix it

[SmurfButcher Bob]

Pretty sure that Emperor Xenu already tried something like that.

Brown Dwarfs

[Anonymous Coward]

Personally If a body doesn't have a core, that sounds like a good place to put the dividing line between planets and brown dwarfs.

An honest question...

[pongo000]

I have an honest question here. Besides the "gee whiz" factor of these new Jupiter observations (and I do find this stuff incredibly amazing), what is the practical application of such knowledge? What can we use this information for to raise the level of the human condition?

Please, an honest answer here. I know this is /., but I'd appreciate an answer other than "it's for the sake of the advancement of science" or some other derivative.

Re:An honest question...

[Anonymous Coward]

Well, can any material we make on earth survive the "center of jupiter" environment, even for just a little bit?

So it's so extreme and exotic, yet those damn hydrogen atoms still refuse to fuse...

So... what are the chance that something we build on earth can contain and sustain a *more* extreme environment (than center of jupiter) to allow controlled fusion on this planet... using materials we build on this planet....

Then again, perhaps jupiter does have low yield fusion that's heating the planet from the inside...

Re:An honest question...

[aiht]

Note, I am not a scientist, but this is my take on the question.

We don't know. There isn't really anything specific and practical that anyone is aiming towards. (In this particular case! I'm not saying we never do that.)
People are researching things that interest them intellectually (while also compromising to get funding, presumably).

Why do we (society) find this to be worth spending money and time on?
From experience, we know that unexpected practical applications often arise from previously pure-theoretical research.
It isn't until we know the answers that we know what use we can make of that knowledge.
Of course, a lot of facts don't go on to become the foundation for a new practical application. But we won't know which are which until after we've done the research.

herp derp....

[Anonymous Coward]

hurrr, im sciencehabit and I can't science space

Re:Who gives a flying fuck?

[Anonymous Coward]

Your leader Sara Palin needs the tubes on her intrawebs fixed.

Re:Who gives a flying fuck?

[coinreturn]

I never said it robbed anyone of value or their own pet project. I just asked "who the fuck cares?" So far, no one has answered whether or not they cared, just objected to my question. Questions are not evil. You and others have drawn too many conclusions from my question.

Re:Who gives a flying fuck?

[aiht]

I care.
There. Happy now?

Re:Who gives a flying fuck?

[DamonHD]

I care: wasn't that clear from my last answer?

Rgds

Damon

Re:Who gives a flying fuck?

[coinreturn]

Who said anything about happiness?

Re:Who gives a flying fuck?

[coinreturn]

Now I see that you did. Usually when someone replies with a long-winded "fuck you" I don't read past the first few parts of the "fuck you." You accuse me of narrow-mindedness, but not thinking an extremely narrow-view is of interest is not narrow-mindedness. I will not be following your advice to not post; when I have something to say, I will say it; even if you don't like it.

venus has an induced magnetosphere

[circletimessquare]

http://en.wikipedia.org/wiki/Atmosphere_of_Venus%23Induced_magnetosphere

Re:Who gives a flying fuck?

[eriqk]

Yes, but what about that other .007 person?

He has a license to kill.

Last to know....

[hesaigo999ca]

My guess is that in the lengthy process that a solar system and/or planet evolves, in which we know nothing about, but can only theorize (as no one has ever lived long enough to see a planet go from a to z), is it possible that there was a core, but the core now has disappeared(on purpose) and that this will create a small vacuum where by the gasses will draw inwards and create a molten core, which in turn will start forming an earth like planet at a much smaller scale, so the large becomes small, and habitable in about 100 million years???

How could we know, really???