Jupiter has no terrain. Is that because

And some other investigators have proposed that the core is made of tar, but I still adhere to the idea that the core is rocky with a mass 15 times Earth's mass, as shown in this page
http://zebu.uoregon.edu/disted/ph121/js19.html

 

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It has been propounded that a liquid mass of sufficient density could generate its own gravitational field?

Liquid / Fluid!

Any object containing sufficient matter to generate it's own powerful gravitaional field can both hold the mass it possesses and also capture any stray matter / mass that finds its way into the objects gravity well. Stresses upon this aquisition would reduce anything short of neutronium to a gaseous form.

An important thing to consider is that all objects, be they a solid, fluid liquid or fluid gaseous object have mass. And so posess gravity.

The one thing that a gravitational mass does very well is increase it's mass and so it's gravity.

Forgive me if I've missed a crucial element to this thread, but gaseous planetary bodies are just that.

This is how simple nebulae work.

For several billion years, Jupiter has been approaching the classification of a protostar. If it were only one power more massive, we would have two suns.

Are we to believe that the sun, Sol, has a solid, truely solid, core?

 

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I started this thread stating that jupiter had no terrain. This is just a discussion about jupiter. Had I not read that Jupiter had no terrain, I would have thought that it had some solid surface below the sea of liquid gas.

It's obvious that some of you (James R, Mac M) are missing the inductive spirit of the discussion so I answer the question that the thread asked: The question: Why doesn't jupiter have terrain? Answer: Because it has been collecting gases for quite some time, one way or another.

Jupiter's magnetic field:

The magnetic field of Jupiter is 19,000 times stronger than the Earth's magnetic field. Even with a large rocky core and high rotation rate, the magnetic field is too strong. The origin of Jupiter (and other Jovian planets) strong magnetic field is the metallic hydrogen shell that surrounds Jupiter's rocky core. Metal is an excellent conductor of electric current and supplies the energy for the generation of an intense and large magnetic field.

A strong magnetic field can capture charged particles from the solar wind (i.e. high speed protons and electrons) and particles ejected from the inner moon, Io. These particles are trapped in the inner magnetic belts and are reflected back and forth between the north and south magnetic poles. - source: http://zebu.uoregon.edu/disted/ph121/js19.html

By rocky core, I'm sure they mean molten rock. Thats not hard to imagine with all the pressure and temperature.

I thought the discussion of if there was terrain or not was solved in the first part of this thread. Then I was arguing that matterial from the sun - solar wind from normal wind conditions, and certainly from solar storms and solar max - contributed to the atmosphere in a significant way did not seem like an unreasonable argument. I think it's bad science to calculate 5 billion years of solar wind and storms from less then 20 years of data. Solar wind is not consistent enough for that assumption. But even if we have a good idea of how much gas has come from the sun in that time, It still contributes to the atmosphere's of all the Mars sized planets and larger. Futhermore, 5 billion years ago the radiation pressure from the sun was just 60% of what it is today. It doesn't take a lot of thinking to understand that the heliopause was not anywhere near where it is today, or that it's probably not uniformly spherical in nature.

BTW esp, that's the first time I think I've ever seen the sun refered to by it's its Latin name, "Sol." :bugeye:

 

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My understanding has been that the solar wind (high energy charged particles) actually tends to strip atmosphere away from a planet, not contribute to it. The solar wind tends to raise the energy level (temperature) of the gas particles in the upper atmosphere, thus increasing the odds that any given gas molecule will reach escape velocity for a given planet.

 

You may be only partially right. When it comes to the small and medium sized planets, it may depend on the extent of the gravity and the distance from the sun (the distance from the sun being a decrease in the number of oppertunities for what may be an averaging of energies). Solar wind does not strip Jupiter of H (the rate of escape of H is exponentially slower) because of the intense gravity. Likewise, the particles are more easily captured. High energy charged particles are just as susceptible to gravity and magnetism as anything else in the universe, it's their speed that makes them different. The stronger the gravity and magnetic field, the higher the likelyhood of capture by a planet. An analogy would be marbles in a bowl. 3 Marbles get thrown fast into the bowl, and 10 come out (Mars). 3 marbles get thrown into a tub and none come out - the three original marbles don't bounce out (Jupiter). Some marbles are smaller and some are bigger (H and He respectively). This analogy works well because gravity is a bending of space - time, like the curvature of the bowl and the tub (although super balls instead of marbles (elasticity of collisions) and a pool instead of a tub may more closely resemble the real thing).
One thing that I think is missed here is if a particle of solar wind has a direct collision with a particle in an atmosphere, the energy can be more or less averaged between the two. So an He traveling at 1/3 c can turn into an He traveling at 1/4 c and an H traveling at approx 1/3 c away from the planet - much like the photoelectric effect, the ability for solar wind to strip atmosphere is independent of the (intensity) distance from the sun (but dependent on gravity and magnetic field intensity). This is why planets such as Mars with an orbit much further away from the sun then Earth or Venus can be stripped of atmosphere to a greater degree. The atoms from the sun that stay within the influence of the planet (and even those that don't) add to the overall average kenetic energy of the atoms in the atmosphere (heat) when they interact with them, increasing the likelyhood of escape of all the atoms in the atmosphere.
So opportunity increases (as a squared value) as the distance to the sun decreases. And it should be said that the likelybhood that a particle escapes the influence of planet decreases as the planets gravity and magnetism increases, but does not eliminate the possibility of escape of a particle. As time goes by, even a planet the size of Neptune loses some particles (But gains much more then it loses). The gas giants obviously pass a point where they are not very likely ,because of their mass, to lose a significant number of particles and actually attracts and retains them.
These charged particles that are captured by a planet might I think be solely responsible for the northern lights - that is without any distortion of the Earths magnetic field, I think these lights would still happen through sheer interaction with the magnetic field (Faraday).

According to the logic that says solar wind only removes gas from atmospheres, Jupiter and Saturn should have been losing H (most easily removed from atmospheres due to obvious reasons) faster then the other gas giants because of their closer proximity to the sun. This has obviously not happened - they have the highest ratios of hydrogen.

Furthermore, as mass increases, so does the ability to retain and attract atmospheres - look at Mars Surface pressure: 6.36 mb. Earths Surface pressure: 1014 mb. Earths is about 150 times greater. Venus surface pressure is 92000mb or 92 bars. If you use a graphing calculator, you can see an obvious relationship between mass, distance from the sun and atmosphere (Uranus has a larger atmosphere then Neptune but weighs less - consistent with my theory that since it is closer to the sun - it has acquired more gas). There are some other considerations: CO2 from volcanic activity, temperature that could evaporate liquids (Venus would have a thinner atmosphere more like Earth if Venus were cooler) - but other then this, mass is a fairly reliable indicator of how much atmosphere is retained and attracted.

Let us consider for a moment nitrogen gas and the atmospheres of Earth and Venus:
VENUS: 3.5% Nitrogen. Total Surface pressure: 92 bars
(% N2 mult. by mb of total gas = 3220 mb N2)
(N has a wt. of 14 on the periodic table)
(1.25 grams per liter at our STP)
Venus gets 1.9113 times the radiation from the sun as Earth does.

Earth: Major : 78.084% Nitrogen (N2) Surface pressure: 1014 mb
(% N2 multiplied by mb of total gass =791.77mb N2)
If we take into consideration the heavier nature of CO2 and O2, vapor pressure and temperature, the amounts of Nitrogen in both of the planets are simmilar.
It is not hard to imagine that some water vapor had been seperated into it's atomic components via radiation, and recombined with carbon. CO2 can be seperated by the power of the sun also, but it's components don't escape the atmosphere as readily as hydrogen does, therefore over time, water vapor slowly is replaced by CO2 until there is little water vapor left.

Is it a coincidence that Jupiter's' atmosphere has a less then a 2 percent difference in composition from solar wind? Dilution increases and is directly proportional to the size of the atmospheres. - The evidence is too compelling! With respect to solar wind - the further a planet is from the sun, the smaller the atmosphere and the less it resembles solar wind. (suppose Saturn started out as almost all hydrogen. It's not hard to imagine severe solar storms that would spew lots of gases into the solar system.

Jupiter Dist. ---778,330---Radius:71,492 -----Mass: 1.90e27 (1.2% approx. Variance (atmospheric components) from solar wind)
Saturn Dist.---1,426,940 ---Radius:60,268. ----- Mass: 5.69e26 (5% approx. variance)
Uranus Dist.---2,870,990 ---- Radius:25,559. ------ Mass: 8.69e25 (7%)
Neptune Dist.---4,497,070 --- Radius:24,764. ------ Mass: 1.02e26 (17%)
The variance from the composition of solar wind has a high correlation coefficient with the distance from the sun with observance to the inverse square law, the radius of the planets themselves, and of the magnetic fields.

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That it does not agree perfectly could be due to the fact that they were captured or created with somewhat of an atmosphere to begin with - and or captured at different times.
Anyone that knows anything about statistical analysis knows that the odds of the numbers 2,5,7,and 17 in order with respect to their distance from the sun is very much in the favor there being some logical reason for it. For example:

The composition of the atmospheres seem directly related to the distance from the sun - That would be enough of a correlation alone, but add to that the fact that the Mass / Solar wind ratio varries more, the further away a gas giant is from the sun and we have very very strong evidence.

It could be a coincidence that as far as the gas giants go, the closer they are to the sun, the larger they are, and the closer they resemble solar wind to a very high degree- AND the gas giants are in order also as to the degree of variance in the mass / wind ratios using Jupiter as a guide but the statistical probability is VERY remote to say the least.

Jupiter :Atmospheric comp. 90% hydrogen, 10% helium, .07% methane
Mass- 1.8986e27
Mean density (kg/m3) 1314
Escape velocity (m/s) 59500
Average distance from Sun 5.203 AU (778,412,020 km)
Perihelion (106 km) 740.52
Aphelion (106 km) 816.62
Orbit eccentricity 0.0489
Dipole field strength: 4.28 gauss-Rj3
Length of day (hrs) 9.9259
NASA Fact Sheet: Atmospheric composition (by volume, uncertainty in parentheses)
Major: Molecular hydrogen (H2) - 89.8% (2.0%); Helium (He) - 10.2% (2.0%)
3.34 x Saturn's mass
3.36 x Saturn's solar wind (1.833 x closer to the sun then Saturn)
21 x Uranus mass
14.8 x Uranus' solar wind
18.6 x Neptune's' mass
33.4 x Neptune's' Solar wind (is 5.78 times closer to the sun)
With respect to Jupiter, the other gas giants'
mass divided by their solar wind - as it relates to
Jupiter.
Sat. ratio M/W= .994
Ura. M/W= 1.42
Nep. M/W= .557
(Please note that the further away the gas planet is from the sun, the more the M/W ratio deviates from Jupiter. This is what we might expect.)
According to this theory, you might expect the planets closer to the sun to be the most alike. If Jupiter was the furthest planet from the sun, it might resemble more what it was like when it was captured.
(Interesting how close Jupiter and Saturn correlate - of course the higher the gas / rock ratio - the easier it is to apply the theory when comparing the mass and the amount of solar wind)

Saturn: 97% hydrogen, 3% helium, .05% methane
Mass- 5.6846e26
Mean density (kg/m3) 690
Escape velocity (m/s) 35600
Average distance from Sun 9.537 AU (1,426,725,400 km)
8 x N's Solar wind
5.6 x N's Mass
Dipole field strength: 0.210 gauss-Rs3
Rotation period 0.444 009 259 2 d (10 h 39 min 22.400 00 s) 1
Perihelion (106 km) 1,352.55
Aphelion (106 km) 1,514.50
Orbit eccentricity 0.0565
NASA Fact Sheet: Atmospheric composition (by volume, uncertainty in parentheses)
Major: Molecular hydrogen (H2) - 96.3% (2.4%); Helium (He) - 3.25% (2.4%)
Minor (ppm): Methane (CH4) - 4500 (2000); Ammonia (NH3) - 125 (75);
Hydrogen Deuteride (HD) - 110 (58); Ethane (C2H6) - 7 (1.5)
Aerosols: Ammonia ice, water ice, ammonia hydrosulfide

Uranus: 83% hydrogen, 15% helium, 2% methane (at depth)
Mass (kg) 8.68 x 1025
Mean density (kg/m3) 1290 - (NASA JPL data)
Diameter (km) 51118
Escape velocity (m/s) 21300
Average distance from Sun 19.19 AU (2,870,972,200 km)
2.55 x N's Solar wind
.86 x N's Mass

Neptune:74% hydrogen, 25% helium, 1% methane (at depth)
Mass (kg) 1.02 x 1026
Mean density (kg/m3) 1640
Diameter (km) 49528
Escape velocity (m/s) 23300
Average distance from Sun 30.07 AU (4,498,252,900 km)
One thing we should keep in mind in the spirit of Kepler: Orbital eccentricities do matter, planets travel faster in the Perihelion and slower in the Aphelion, so we should figure that into our calculations in the accumulation of solar particles. The higher the eccentricity, the more the average wind will deviate from the average distance. The average should be based on the time the planet spends in each respective distance.
Some of my conclusions are: Neptune started out as a very large rocky mass but was captured in a more distant orbit and possibly that Neptune and Uranus were captured more recently then Saturn and Jupiter, consequently Neptune and Uranus did not acquire as much gasses (due to time and distance) from the sun. Saturn may have been captured about the same time as Jupiter but as a almost entirely hydrogen planet.

Look at the distances and the masses of the gas giants. Saturn is not quite twice the distance, and not quite 4 time smaller then Jupiter. These data from the gas giant planets agree very well with the proportion of substance coming from the sun. If you take in to account the differing amounts of rock/metal core that they started out with, and varying times of capture the variance between the planets make some sense. Neptune obviously started out much larger then many other planets.
But the most compelling argument is how close Jupiter and Saturn's' masses correlate with their distance from the sun:
Jupiter is 3.34 x Saturn's mass
Jupiter also gets 3.36 x Saturn's solar particles from the sun
Assuming that Jupiter and Saturn started out significantly larger then the Earth, (they would have to have had higher escape velocities then Earth) we would expect Jupiter to Saturn's mass to be a smaller ratio then the solar wind ratios. In other words what we see is what we would expect to see.
If Jupiter actually started out smaller then Saturn - it could have lost more hydrogen gas initially then Saturn, that and the fact that we might expect planets further away to be more dilute with respect to the gasses coming off of the sun, might in part explain the differences in the atmospheres. In other words Jupiter could have been captured as a planet with a slightly stronger escape velocity then Earths and wasn't able to retain the lightest element until later in it's history. But the argument could be made that Saturn was the older and got a higher percentage of hydrogen from the sun when the sun was a higher percentage of hydrogen (and the solar wind also). There are many possibilities and many of the possibilities could have played a role - for example either planet could have been in the solar system much longer then the other, and may have been captured with some atmosphere in place.
It may not be stretch to think that early in the solar systems history, the solar wind might have had a higher ratio of hydrogen then it does today. It may not be inconsistent with the data to say that Saturn may have been the larger planet of the two at some point or relative to its own beginning in the solar system. If Saturn was captured earlier (and or possibly smaller) then Jupiter and received a different composition of wind, this may not be inconsistent with the data.
Photosphere Composition (SUN):
Major elements: H - 90.965%, He - 8.889%
JUPITER Major: Atmospheric composition (by volume, uncertainty in parentheses)
Major: Molecular hydrogen (H2) - 89.8% (2.0%); Helium (He) - 10.2% (2.0%)

The Solar Wind Spectrometer was deployed on Apollo 12 and 15. Although the solar wind contains ions of most chemical elements (including the noble gases measured by the Solar Wind Composition Experiment), over 95% of the particles in the solar wind are electrons and protons, in roughly equal numbers. The Solar Wind Spectrometer measured the flux of protons and electrons as a function of particle velocity. The measurements were made in a set of seven detector cups with different orientations in order to determine the direction of particle motion. Most of the measured flux was in the detector that was oriented most directly toward the Sun. (Lunar and Planetary Institute)
Table 1. In-situ measured and estimated solar-wind fluences for Genesis collectors.
-------------- SRC Lid B & C Arrays --Interstream --Coronal Hole --CME
Exposure (days)----886.84 ---852.83 ----333.67 --313.01 --193.25
H fluence (cm-2)--------1.9e16 ---1.9e16 ---8.3e15 ----5.9e15 --4.0e15
He fluence (cm-2)-------7.3e14 ---7.2e14 ---2.8e14 ----2.1e14 --1.8e14
O fluence (cm-2)--------4e12 ----4e12 -------2e12 ----1e12 ---- 1e12
(Lunar and Planetary Institute)
It should be said that the ions that are in the solar wind can be said to be redirected by the magnetosphere to the poles of the planets just as any particle with a charge is attracted to one pole or the other of a magnet. The particles with no charge are unaffected by magnetospheres. The Earth is a magnet, and protons are as much attracted to the negative pole as they are repelled by the positive pole. Overall there is a net attractive force that actually attracts particles from a much larger area then the visible surface of the Earth. Net attractive force because the more the particle is deflected from it's original course, more times then not it is directed to the attractive pole. I believe that anyone in a lab that fired charged particles at a very large magnet (with the Earth - it is not the strength, it is the size of the magnet - the time of exposure of the particle to the field) would be hard pressed to hit the magnet less times then a target that had no charge. This might explain one of the reasons that the magnetic poles move around with respect to the surface of the planet. Enough electrons to the positve pole of the Earth and enough Protons to the negitive pole, would tend to weaken the respective poles.

We see everything we might expect to see in this case with possibly one exception: We expect some variance with the respect to the composition of the gas giants, but the variance in H and He between Jupiter and Saturn seems to be the most significant for several reasons. Perhaps this is because the truth of the formations of the planets lay in the middle of two or more theories. Jupiter is closer to the sun and might have more oppertunity to have H baked off and or knocked out of the atmosphere. But it should be said that a photo - electric type effect seems to be most significant in the removal of H. Consider the atmospheres of Mars and Venus. If solar storms heated up the atmosphere and caused the removal of gasses, - if this were the only consideration, Mars would have the thicker atmosphere. It has many many times less wind particles then Venus yet Venus has a very thick atmosphere and Mars has a very thin atmosphere, less then .01% of what Venus is. This is very consistent with my theory, and very inconsistent with the common notion that solar wind only removes atmospheric particles by way of heat.

MARS Surface pressure: 6.36 mb (about 14,500 times less then Venus)
Mars Black-body temperature (K) 210.1
Solar irradiance (W/m2) Mars 589.2
Surface gravity (m/s2) Mars 3.71

VENUS Solar irradiance (W/m2) Venus 2613.9
Surface gravity (eq.) (m/s2)Venus 8.87
VENUS: Total Surface pressure: 92 bars

Venus:
Total mass of atmosphere: ~4.8 x 1020 kg
Average temperature: 737 K (464 C)
Mars:
Total mass of atmosphere: ~2.5 x 1016 kg
Average temperature: ~210 K (-63 C)

I think these numbers clearly indicate that there is more to the story of the loss of atmospheres then heat.


But the argument could be made that the data, in light of what we observe, does not vary from the theory: Saturn and Jupiter are either within or very close to being within the uncertainty of the exact composition of solar wind and solar storms- this difference is not very much at all and may easily be explained by any or all of the following: Slightly higher rate of loss of H. The photo - electric type effect could solely explain the difference because the prevelence of high speed particles from the sun is about 4 times greater per sq. ft. then that of Saturn. This would make sense in light of Jupiters M/W ratio being slightly smaller then Saturn (3.34 x Saturn's mass and 3.36 x Saturn's solar wind). Initial composition, and time of formation could have played a role, but according to this theory is not responcible for but a small fraction of the masses of the two biggest gas giant planets in our solar system.

So when we try to reconcile these theories with what we have observed with respect to planets discovered in distant star systems, it could be said that depending on the amount and energy of radiated particles from the stars involved, and the planets distance from the star, it might be possible to explain much of what we see in terms of the masses of the gas giant planets discovered so far. Too many solar particles too close to the sun may actually strip more particles then the planets retains. Electro magnetic radiation contributes to the average kinetic energy of the particles in the planets atmospheres (heat).

These theories should be viewed as basically stating that the the masses of the gas giants are not entirely arbitrary in nature, and that it is possible that a significant amount of the masses of these planets could be from the host star.

For example:

- http://www.astro.uiuc.edu/~kaler/sow/14her.html

It could be that due to the limitations in discovering planets, gas giants are harder to detect further away, or it could tell us something about the planets.

Another example: The class F star Upsilon Andromedae (in the constellation Andromeda).

The planets: Farthest out, at 5.9 Astronomical Units (AU) from the star, is the most massive, 55 Cnc-d, which is at least 4.1 times the mass of Jupiter and takes 14.7 years to orbit.

The other three are much closer and less massive. Next in order are 55 Cnc c, b, and e with minimum masses of 0.21, 0.84, 0.045 solar, orbital radii of 0.24, 0.11, 0.038 AU, and periods of 44, 14.7, and 2.81 days. The existence of 55 Cnc-c is questionable. 55 Cnc-e has the smallest measured minimum mass, only about that of Uranus or Neptune. It is also closest to its parent star.
The class F star: Temperature of 6210 Kelvin and luminosity 3.4 times that of the Sun suggest a mass 1.3 times solar and a radius 60 percent larger than the Sun.
So in considering this case, we might not be supprised at the order of the size of the planets because of the intense radiation, and the heat that it generates.

Let us look at another interesting example:

- http://www.astro.uiuc.edu/~kaler/sow/47uma.html

This may be a good example, because the star closely resembles ours.

The innermost planet (A) devided by planet (B) = .563
B divided by A = 1.78 (planet B is 1.78 times further away)
1.78^2= 3.168 (planet B only gets 1/3.17 times the radiation A gets.)

Mass A / Mass B = 3.16

So in this example, 47 Ursae Majoris and it's planets agree almost perfectly with the theories - and this solar example is the closest to our own solar system in many ways.
It may not need to be said, but the certainty of the exact masses of these planets is not as important as the ratios between the planets. The ratios may be more accurate because they are most likely in the same orbital plane and vary from the minimum masses the same amount.

 

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I agree master yoda, gasses must meet the ideal critical temperature and pressure in order to become liquids. i wouldn't doubt high pressure existing on Jupiter, but temperature must initiate van der waals attraction between the molecules to support matter of lower entropy.:shrug::bugeye:

 

why couldn't a rocky core and liquid mantle not be considered terrain?

 

I think we usually associate "terrain" with clearly defined solid surfaces. E.g.

- The solid surface of the earth

- The icy surface of something like the moon Europa

- The floor of the ocean (ocean floor terrain)

So, if the rocky core of a gas giant like Jupiter (if it even has one) could ever be probed, I would say that the features you might see could be called terrain.

 

No evidence ? What about the countless meteors and comets that crashed into it ?

 

Well, I think the atmosphere above the (solid) core is generally thought to be dense enough so that the meteors never actually get to the surface. I think.

 

You're right. Not even close to whatever could be called a surface.

 

Well, I know there is a core on Jupiter of solid iron (again...I think). But it would still be under tremendous pressure and heat, and so it is probably liquid and spherical.

 

Maybe..
But Tortise originally asked:

To which Light responded:

See, it wasn't about the core..

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The weight of that much gas would cause some sort of solid to form in the center. Likely, the planet started very much as our own earth, trapping gases left over after the previous star supernova-ed. This is speculation (I'm not an expert in this field), but it is well-informed speculation.

 

It's all about the liquid metallic hydrogen:

http://csep10.phys.utk.edu/astr161/lect/jupiter/interior.html

 

Ahh. Thanks for the link.

So this should settle it. Any final comments before I lock the thread?

 

Well, if you`re going to lock the thread anyway: STRINGS RULE!!!

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Strings ? lol

 

p-brane is right. Case closed.

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