New calculations suggest Jupiter's core may be liquefying

Dec 21, 2011 by Bob Yirka report
Jupiter. Photo courtesy of NASA

(PhysOrg.com) -- Jupiter, the largest planet in our solar system, may be causing its own core to liquefy, at least according to Hugh Wilson and colleague Burkhard Militzer of UC, Berkeley. They’ve come to this conclusion after making quantum mechanical calculations on the conditions that exist within the big planet. In a paper published on the preprint server arXiv, and submitted to Physical Review Letters, the two explain that because the gas giant has a relatively small core made of mostly iron, rock (partly magnesium oxide) and ice, and sits embedded in fluid hydrogen and helium all under great pressure from the planet’s gravity (which has created very high temperatures (16,000 K)), there is a likelihood that the core is liquefying due to the heat and pressure exerted on the magnesium oxide.

Calculating the possibility of the magnesium oxide liquefying had to be done to predict the outcome because recreating the environment that exists inside of Jupiter for experimentation purposes isn’t feasible. They have in essence shown that , when exposed to such high temperatures and pressure, has high solubility, which of course means a high probability of dissolving into a liquid. In a previous study, the team also made calculations showing that the core ice would likely be dissolving as well.

The findings suggest that Jupiter’s core might not be as big as it once was, though it currently weights about as much as ten Earth’s (the whole planet weighs as much as 318 Earth’s). This implies that the core could eventually be reduced down to nothing at all. And if that’s the case, than those who study exoplanets, particularly the giant gas variety, will have to do some rethinking, because those others might not have a core at all, contrary to conventional wisdom.

Unfortunately, the calculations the two performed can’t give a rate of erosion, thus a timeline for how long it’s taken for the core to come to its current size can’t be made, nor can predictions be made on how long it might take for the core to disappear altogether; both of which would be useful in helping to predict the ages of other gas giants out beyond our . Luckily, NASA has a space probe on the way to measure ’s gravitational field more accurately, though it won’t get there till 2016; that should give scientists plenty of time to consider the impact these new findings might have on their current models regarding giant gas planets.

Explore further: Why is space black?

More information: Rocky core solubility in Jupiter and giant exoplanets, arXiv:1111.6309v1 [astro-ph.EP] arxiv.org/abs/1111.6309

Abstract
Gas giants are believed to form by the accretion of hydrogen-helium gas around an initial protocore of rock and ice. The question of whether the rocky parts of the core dissolve into the fluid H-He layers following formation has significant implications for planetary structure and evolution. Here we use ab initio calculations to study rock solubility in fluid hydrogen, choosing MgO as a representative example of planetary rocky materials, and find MgO to be highly soluble in H for temperatures in excess of approximately 10000 K, implying significant redistribution of rocky core material in Jupiter and larger exoplanets.

via Wired

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MorituriMax
1.6 / 5 (13) Dec 21, 2011
It's probably our fault too, like everything else.
Isaacsname
1 / 5 (1) Dec 21, 2011
Ugh, I feel like I'm doing the same....
Sonhouse
5 / 5 (4) Dec 21, 2011
Anyone know how they came up with the idea that magnesium oxide might be part of the mix?
El_Nose
3 / 5 (4) Dec 21, 2011
any clue as to why this phenomenal act might be starting to occur right now --
Osiris1
1.9 / 5 (9) Dec 21, 2011
Could that core be settin up to start a fusion reaction and initiate Jupiter as a Star?
Nanobanano
2.4 / 5 (14) Dec 21, 2011
any clue as to why this phenomenal act might be starting to occur right now --


It makes no sense within the "standard model" of SS formation.

After all, supposedly the planets accreted billions of years ago,and lost most of their heat since then.

Indeed, Jupiter is allegedly radiating away more heat than it receives from the Sun, therefore, if anything Jupiter "should" be solidifying and becoming more dense, not the other way around.

Additionally, according to NASA, Jupiter is supposedly shrinking in radius right now at a rate of a few centimeters per year.

Point being, if something has allegedly been cooling for billions of years, it should not suddenly start re-heating it's core. That's absurd and as they say, "Something's Gotta Give".
antialias_physorg
3.7 / 5 (6) Dec 21, 2011
Could that core be settin up to start a fusion reaction and initiate Jupiter as a Star?

Jupiter's mass is too low for that.

any clue as to why this phenomenal act might be starting to occur right now

Where do you get the indication that this is staring just now?

Point being, if something has allegedly been cooling for billions of years, it should not suddenly start re-heating it's core.

Shrinkage means more density. More density means more gravitational effect closer to the core.

Remember that AT the core of any planet gravity is zero. gravity at a set distance outside, however, is the same if the mass stays the same. So the gravity magnitude can shift within a planet if the surface recedes (i.e. the distribution magnitude of gravity as a function of depth can vary if parts of it shrink not uniformely)

Higher gravity (i.e. pressure) at some depth can lead to heating and hence melting of volatile substances.

Just my knee-jerk analysis....
Osiris1
1 / 5 (1) Dec 21, 2011
If it really does become a brown dwarf, what of its moons...er...new 'planets'?
stellar-demolitionist
4.8 / 5 (5) Dec 21, 2011
any clue as to why this phenomenal act might be starting to occur right now --


Nothing implied that it is starting now. If the core does dissolve, it could have started a billion years ago, or it might not start for another billion years.

What is happening now is that better calculations of material properties at those densities are becoming available, and soon there will be a better measurement of Jupiter's density profile.

Combined those will place restrictions on what materials can be were inside Jupiter, and if any core dissolution has taken place.
antialias_physorg
3 / 5 (4) Dec 21, 2011
If it really does become a brown dwarf, what of its moons...er...new 'planets'?

What of them? They'll contimue on exactly as before.
Argiod
1.8 / 5 (9) Dec 21, 2011
So, what does this mean for Jupiter? What if Jupiter is NOT a planet at all, but a cooled off sister star to the Sun?

Would this re-ignite what I believe to be our Sun's sister star? What would the solar system be like with two active stars?
If it reignites, would that destabilize the system? How would it affect life on the Earth?
I'm not saying this is what's happening; but it deserves some consideration; and would make for a great new premise for a rousting good Sci Fi Thriller.
Pirouette
2.3 / 5 (12) Dec 21, 2011
Morituri Max says:
It's probably our fault too, like everything else.


No, it's Bush's fault. :)
FrankHerbert
0.9 / 5 (56) Dec 21, 2011
Moderators please remove the above comment for being "OFF TOPIC". Thank you.
UnlimitedRealms
5 / 5 (2) Dec 22, 2011
Arigoid - Jupiter is too small in mass to ignite in to a stellar body and never has . And there was a movie about such a thing but it took an alien artifact to pull it off - Remember " 2010 - The Year We Make Contact " it was the sequal to " 2001 - A Space Odyssey ".
bewertow
2.9 / 5 (7) Dec 22, 2011
omatur is so annoying. I hope they put him in prison for child molestation already so he can stop posting all his nonsense.

antialias_physorg
3.7 / 5 (3) Dec 22, 2011
What if Jupiter is NOT a planet at all, but a cooled off sister star to the Sun?

Jupiter is one of those 'stars that never made it'. It doesn't even have enough mass to be a brown dwarf.
Brown dwarfs are themselves substellar objects - i.e. no fusion going on - with between 13 to 80 times the mass of Jupiter.

So you can see: Jupiter has less than 10% of the mass it takes to even classify for the next higher (non-stellar) category. No. It never will be a sun and never has been.
Osiris1
1.6 / 5 (7) Dec 22, 2011
We really do not know everything. If we did we could simply drive there in our saucers and check it out, or would not need too inasmuch as we assumably would have already observed this many years ago. Immune to gravity wells, temperature and pressure....(observably by witnesses 'discredited by governments to at least have folks not listen to them even if those governments saw it "inconvenient to shoot them")[put this in for the pathoskeptiks], our craft could then see this first hand and THEN come up with a reason why...we always DO this after some principal like 'Einstein' gets broken. Watch 'em dance..on both sides with equal intensity. We see new stuff all the time, followed by those explanations that previously existed but were buried by their authors for fear of losing: jobs, house mortgages, child custody, their freedom!, etc. We are not certain of this either, but SHOULD watch! No danger to solar system unless Jupiter explodes! Or directs an X-ray jet this way..improbabl
rubberman
2 / 5 (4) Dec 22, 2011
Osiris....aren't those lyrics to a "beck" song?
LuckyBrandon
1 / 5 (1) Dec 23, 2011
Could that core be settin up to start a fusion reaction and initiate Jupiter as a Star?


lol i had the same thing cross my mind...ah watch this thing convert into a star and really screw up our cozy orbit

Moderators please remove the above comment for being "OFF TOPIC". Thank you.

Don't defend Bush, you only help to vindicate the morons who supported him as a presidential candidate...his track record speaks for itself...
antialias_physorg
3.3 / 5 (3) Dec 23, 2011
lol i had the same thing cross my mind...ah watch this thing convert into a star and really screw up our cozy orbit

How would that screw up our orbit? The mass stays the same so the gravity stays the same.*

That's one of the things people don't understand (especially about black holes). These things don't suddenly have a bigger gravitational attraction after a star turns into a black hole (or after a ball of hydrogen initiates fusion and becomes a star). At the disteance equivalent to the radius of the former star's surface and beyond the gravity stays EXACTLY the same.

Only (very much) closer to the center of a black hole things get crazy.

*We'd just have a (tiny) bit more ligh. Jupiter has one thousandth of the mass of the sun and is 5 times as far away from us as the sun is. So even if it could turn into a sun it would only be marginally more visible than it is now.
Sinister1811
1.1 / 5 (7) Dec 26, 2011
Reason would also dictate that the same thing is happening to Saturn's core. Or is Jupiter marginally bigger than Saturn, so much so, that this could only happen on Jupiter?
Sinister1811
1 / 5 (5) Dec 26, 2011
Could that core be settin up to start a fusion reaction and initiate Jupiter as a Star?


Doubtful. Jupiter doesn't have enough mass to support nuclear fusion. It's not even large enough to be a Brown Dwarf.
LuckyBrandon
1 / 5 (2) Jan 08, 2012
@antialias - would the mass stay the same if said gases began to burn off?
antialias_physorg
5 / 5 (1) Jan 08, 2012
Ermm..where would they 'burn off' to? The stuff is atoms pre and post combustive reaction. As such every atom/molecule is still subject to gravity. The atoms in it still have the same mass - so they will stick with the planet just the same as they did before.

The sun loses a bit of mass due to ejection of mass in solar flares. But we're talking thermonuclear fires and massive magnetic fields here - none of which are part of what Jupiter can do.

Of course the solar radiation equates to a loss of mass (IIRC about 4 million tonnes per second)..but that is small fry compared to the size of the sun.
Shelgeyr
1 / 5 (3) Jan 09, 2012
...the two explain that because the gas giant has a relatively small core made of mostly iron, rock (partly magnesium oxide) and ice, and sits embedded in fluid hydrogen and helium...


Ummm, no.

By which I actually mean "yeah, maybe", but this is the sort of statement that should NOT be stated as a fact since we flat don't know if it is true. It certainly MAY be, but we have no evidence to support that statement, and "evidence" is kind of "the big important thing" in science. Or at least it is supposed to be.

Since this study apparently takes this statement as a true factual given, the conclusion shouldn't be taken seriously. Even if their math is otherwise correct.

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