Jupiter has no terrain. Is that because

Discussion in 'Physics & Math' started by Tortise, Oct 21, 2005.

Thread Status:
Not open for further replies.
  1. Tortise Registered Senior Member

    Messages:
    227
    Gas has condensed and there is liquid hydrogen other liquid gasses at the surface? The pressure would increase condensation of the gasses.

    (Gassy Jupiter, with no solid surface or terrain, is nothing but weather, unchanged by seasons because the planet sits upright on its axis. "Every identifiable feature resolves into a cloud bank, a cyclone, a jet stream, a thunderbolt, or a curtain of auroral lights," Ms. Sobel writes. "On Jupiter, a storm may continue for centuries, innocent of landfall." )
    I think I would sooner believe that it has terrain, but that it is somewhat beneath the ocean of liquids.
     
  2. Google AdSense Guest Advertisement



    to hide all adverts.
  3. Light Registered Senior Member

    Messages:
    2,258
    You might think that, but it's incorrect. In order for gasses to become solid (liquid too, for that matter) there's a set of conditions that have to be met. One is termed "critical temperature" and even though it's cold, the temperature on the surface of Jupiter in not below the critical temp needed for those gasses to form solids.
     
  4. Google AdSense Guest Advertisement



    to hide all adverts.
  5. Tortise Registered Senior Member

    Messages:
    227
    I'm aware of that but why wouldn't the planet be comprised of various things as well as gasses?
     
    Last edited: Oct 23, 2005
  6. Google AdSense Guest Advertisement



    to hide all adverts.
  7. Light Registered Senior Member

    Messages:
    2,258
    So far, there's no evidence of it. However, there's a pretty good chance that it has a rocky center resulting from stony material it's captured. But that could hardly be called a "surface." And wouldn't qualify as topology.
     
  8. Tortise Registered Senior Member

    Messages:
    227
    what evidence is there that it is almost entirely gas? This flies in the face of some theories of how the solar system was created (which doesn't mean it's not true) but I'm wondering how we know this (and if it's correct) when we can't even send in a probe.
     
  9. Light Registered Senior Member

    Messages:
    2,258
    Sorry? Don't quite understand what you mean. There are no gasses at the center. There would be only what stony masses have been captured and liquids.
     
  10. fo3 acdcrocks Registered Senior Member

    Messages:
    552
    The models that predict the formation of the solar system quite accuratey are enough of a proof in this case. It was not physically possible for so much dust and debris to be at that distance from the sun at the time of formation of the solar system, to form a solid planet of that size.
    Also the low average density of Jupiter does not allow for much of solid material below the clouds. Ofcourse there is some solid material at the core about the size of the earth, but as someone already said, it can hardly be considered as a surface.
     
  11. Tortise Registered Senior Member

    Messages:
    227
    Well, I'm sure what you say is true, but you said: "Ofcourse there is some solid material at the core about the size of the earth, but as someone already said, it can hardly be considered as a surface."
    Wouldn't it make sense then that the pressure from such a massive planet would turn any matterial at the core to liquid as well? (which is probably your point anyway) Ok I get it.
     
  12. Tortise Registered Senior Member

    Messages:
    227
    Also you said "It was not physically possible for so much dust and debris to be at that distance from the sun at the time of formation of the solar system"
    According to Kepler's law dust would orbit the sun as easily as any other elements in that it is independent of mass? A more massive body would be more able to retain light gasses though right?
     
  13. Tortise Registered Senior Member

    Messages:
    227
    Also it must certainly be no accident that the gas giants are further from the sun in that it is the solar wind that removes gas from the atmosphere. Mars has very little atmosphere, and would have even less if it were as close as Earth to the sun. So it is a function of mass and distance from the sun. Jupiter might still be a gas giant if were in a murcury type orbit because of the mass. GR tells us that everything falls at the same rate ( a feather would fall at the same rate as a lead ball in the absence of atmosphere) so an atom of lead would fall to the moon at the same rate that an atom of hydrogen. It is solar wind and mass that is often the deciding factor for atmospheric formation. Jupiter must have had initially enough mass to capture hydrogen in my opinion.
     
    Last edited: Oct 22, 2005
  14. fo3 acdcrocks Registered Senior Member

    Messages:
    552
    Firstly, gas has pressure, which the dust has not. This causes the gas to move a bit slower around the sun, because the pressure already covers a part of the centrifugal force needed to keep the gas on orbit. Dust and small particles encounter friction moving through this slower gas, lose energy and fall a bit closer to the sun, until there is little enough gas at the distance. The gas in the same time constantly increases its energy, as it is heated up by the light from the sun, and is pushed further away from the sun by its own pressure. In fact if there is too little dust at the inner region, then the gas can almost completely be blown away from the sun.
     
  15. fo3 acdcrocks Registered Senior Member

    Messages:
    552
    Initially there was only a disc of gas and dust. At the location of Jupiter, there was a lot of gas for the formation of a planet.
     
  16. Tortise Registered Senior Member

    Messages:
    227
    Never the less, you have to admit that it retains gas more efficiently and attractes hydrogen from solar wind to a greater degree.
     
  17. Tortise Registered Senior Member

    Messages:
    227
    stream of ionized hydrogen–protons and electrons–with an 8% component of helium ions and trace amounts of heavier ions that radiates outward from the sun at high speeds. The continuous expansion of the solar corona into the surrounding vacuum of space carries away from the sun about 1 million tons of gas per sec; this blows out like a wind through the solar system
    The atmosphere of Jupiter is composed mainly of hydrogen, helium, methane, and ammonia. However, the concentration of nitrogen, carbon, sulfur, argon, xenon, and krypton–as measured by an instrument package dropped by the space probe Galileo during its 1995 flyby of the planet–is more than twice what was expected, RAISING QUESTIONS about the accepted theory of Jupiter's formation. (yahoo encyclopedia)

    Hmmm.... 1 million tons of gas per sec from the sun....I'm willing to bet that over the course of billions and billions of years, that this would have an effect on the make up of Jupiter to some degree - The gravitational AND magnetic fields can serve to attract solar wind. While deflected by the positive pole, ions are attracted by the negitive pole. It has much the same makeup of the sun. Is that in part because it has accumulated much of the solar wind? And considering the planets Saturn, Uranus, Neptune . . Should we ask ourselves if this is not inconsistent (not insignificantly) with the distribution of solar wind?

    "Auroral emissions, similar to Earth's northern lights, were observed in the polar regions of Jupiter. The auroral emissions appear to be related to material from Io that spirals along magnetic field lines to fall into Jupiter's atmosphere."

    "Jupiter has no solid rock surface. One theory pictures a gradual transition from the outer ammonia clouds to a thick layer of frozen gases and finally to a liquid or solid hydrogen mantle. Beneath that Jupiter probably has a core of rocky material with a mass 10—15 times that of the earth." (yahoo)

    If 10-15 times the mass of Earth at the core is rocky matterial, then that would be enough to retain and attract solar wind.

    "Jupiter has a huge asymetrical magnetic field, extending past the orbit of Saturn in one direction but far less in the direction of the sun. This magnetosphere traps high levels of energetic particles far more intense than those found within earth's"
     
    Last edited: Oct 22, 2005
  18. James R Just this guy, you know? Staff Member

    Messages:
    39,397
    There was a theory at one stage that Jupiter might actually have a core made of pure diamond. I'm not sure what today's astronomers think of the idea.
     
  19. fo3 acdcrocks Registered Senior Member

    Messages:
    552
    This one million tons of gas is distributed more or less equally around the sun.
    And Jupiter is so far away from the sun, that this gas is spread out over a huge area, so that Jupiter really cant pick up that much material to affect its mass or composition.

    Are you now suggesting that Io contributes to the makeuo og Jupiter aswell?

    To some degree, it would be yes, but why on earth do you want to use the mass of the Jupiters core instead of the entire Jupiter? Anyway, earth has northern lights aswell. I dont see our planet having a hydrogen layer around it.
     
  20. fo3 acdcrocks Registered Senior Member

    Messages:
    552
    Mass of Jupiter: 1.4 x 10^27 kilograms
    Age of Jupiter: ~6 billion years = 1,89 x 10^17 seconds
    Gas from the sun: 1 000 000 tons/sec = 1 000 000 000 kg/sec
    Gas from the sun during Jupiters existence: 1,89 x 10^26 kg

    That is a bit over 10% of Jupiters current mass, that the sun would have radiated out as gas during the entire existence of the solar system, if the rate is considered constant. Assuming that Jupiter has catched ALL of this matter, then it would have some effect on it, but not as much as you were suggesting.
    If we think realistic now, then Jupiter can't even catch a fraction of a percent of all this gas from the sun.
     
  21. DaleSpam TANSTAAFL Registered Senior Member

    Messages:
    1,723
    Diameter of Jupiter: 1.43E8 m -> cross sectional area = 1.61E16 m^2
    Distance from Sun: 7.78E11 m -> surface area of sphere = 7.61E24 m^2
    Ratio = 2.11E-9
    Gas from Sun in Jupiter's direction = 4.00E17 kg

    If we make Jupiter's effective radius for pulling in dust equal to = 2.37E10 m (the orbital radius of its most distant moon, Sinope), then we get
    Ratio = 2.32E-4
    Gas from Sun in Jupiter's direction = 4.38E22 kg

    Not very much compared to the total mass. But it does represent about 31 ppm (best case). It would definitely be detectable if it could be "tagged" as gas from the sun, but I don't know if that is possible.

    -Dale
     
    Last edited: Oct 22, 2005
  22. Tortise Registered Senior Member

    Messages:
    227
    I was speculating on how a jupiter could have formed the way it is today from a mass of rock 10 - 15 times the size of the earth, and I think to some degree - the hydrogen layer is the oceans. H combines with O. But even the earth loses hydrogen to space at a much much faster rate then jupiter (about 10,000 x faster) because of jupiter's immense gravitational field. Also H readily combines with things - hence it's use as hydrogen fuel and it's place in acid / base scale.

    Also fo3 said: "Are you now suggesting that Io contributes to the makeuo og Jupiter aswell?" - No, I'm not suggenting that because they are not massive enough to retain an atmosphere - much like our moon. If you consider mars, you see a planet that is on the cusp of retaining an atmosphere - this almost entirely dependent on the mass of the planet. Much like the photoelectric effect (but matters to a lesser extent because interactions can be cumulative in that an atmospheric particle can be hit several times to give it enough energy to leave the atmosphere), no matter the distance will only decrease the number of interactions - not the power of the radiation hitting the atoms in the atmosphere. The ability to retain and attract is dictated by the gravitational and to some extent the electro-magnetic field, and the opportunity is dictated by the distance from our sun.

    - or did I misunderstand your question? I think your question was does Io contribute to the makeup OF Jupiter? According to that article I would say that it implied that it did to some extent. Much like our moon, it would attract solar wind but could not hold on to it. So Earth's ability to attract would include the mass of the moon, but Earth would be the sole beneficiary of the H and He. Make sense? This would work the same for the moon's magnetic field if it were to have a significant one. The area of influence that Jupiter can capture solar wind is significantly more then the what is represented by the size of the planet it's self. Also a significant amount of slower moving H and He, (that was once solar wind that other closer smaller planets have captured and lost) has been accumulated by Jupiter and the other larger planets.

    "Jupiter's Auroras Helped by Io" http://www.universetoday.com/am/pub...ora.html?232005

    "If we think realistic now, then Jupiter can't even catch a fraction of a percent of all this gas from the sun." Certainly you are correct. I am saying that solar wind has contributed significantly to the makeup of Jupiter, and that the heliopause we observe now, certainly does not reflect the way it has always been. It most certainly has changed and may have a more or less significant effect on the makeup of our planets.

    The most dense part of Jupiter is not the H and He anyway (the core of Jupiter) so subtract all that is not H and He (which is significant), and then consider that our sun goes through a life cycle and that the heliopause may not have always been so far away - and perhaps we can imagine that Jupiter could have started out as a much different planet. - (which may have been what you were saying all along) my argument is that solar wind has contributed (even by your calculations) to the makeup of Jupiter, and that it may not be a coincidence that there is a receding nature to the masses of the gas giants the further away they are from the sun.

    Then open your mind even further and consider other possibilities such as Jupiter may have been accumulating gas before the formation of our planet and was captured by our sun - am I saying this is what happened? No. I'm saying it is a possibility. Any massive body like Jupiter will accumulate H and He even in open space, and is either eventually captured by (in an orbit) or becomes part of a what is or what will be (after becoming one with) a more massive body.

    Distance Radius Mass
    Planet (000 km) (km) (kg)

    Mercury 57,910 -2439 -3.30e23
    Venus 108,200 -6052 -4.87e24
    Earth 149,600 -6378 -5.98e24
    Mars 227,940 -3397 -6.42e23
    Jupiter 778,330 -71492 -1.90e27
    Saturn 1,426,940 -60268 -5.69e26
    Uranus 2,870,990 -25559 -8.69e25 Herschel 1781
    Neptune 4,497,070 -24764 -1.02e26 Galle 1846
    Pluto 5,913,520 -1160 -1.31e22 Tombaugh 1930

    heliopause is located about 153 to 158 AU (14.3 to 14.7 billion miles)


    Jupiter : Atmospheric components 90% hydrogen, 10% helium, .07% methane
    Mean density (kg/m3) 1314
    Escape velocity (m/s) 59500
    Average distance from Sun 5.203 AU (778,412,020 km)


    Saturn: 97% hydrogen, 3% helium, .05% methane Mean density (kg/m3) 690
    Escape velocity (m/s) 35600
    Average distance from Sun 9.537 AU (1,426,725,400 km)
    Mean density (kg/m3) 690 -NASA-JPL

    Uranus: Atmospheric components 83% hydrogen, 15% helium, 2% methane (at depth) Escape velocity (m/s) 21300 Average distance from Sun 19.19 AU (2,870,972,200 km) - (NASA JPL data)

    Neptune: Atmospheric components 74% hydrogen, 25% helium, 1% methane (at depth)
    Mean density (kg/m3) 1640
    Escape velocity (m/s) 23300
    Average distance from Sun 30.07 AU (4,498,252,900 km)


    Uranus is composed primarily of rock and various ices, with only about 15% hydrogen and a little helium (in contrast to Jupiter and Saturn which are mostly hydrogen). Uranus (and Neptune) are in many ways similar to the cores of Jupiter and Saturn minus the massive liquid metallic hydrogen envelope. It appears that Uranus does not have a rocky core like Jupiter and Saturn but rather that its material is more or less uniformly distributed . (This may be because as the gravitation field increases, so also does the differentiation of material, and hence the layering in order of density)

    Neptune's orbit: 4,504,000,000 km (30.06 AU) from Sun
    diameter: 49,532 km (equatorial)
    mass: 1.0247e26 kg
    Neptune's composition is probably similar to Uranus': various "ices" and rock with about 15% hydrogen and a little helium

    from the Galileo atmospheric probe also indicate that there is much less water than expected. The expectation was that Jupiter's atmosphere would contain about twice the amount of oxygen (combined with the abundant hydrogen to make water) as the Sun. But it now appears that the actual concentration much less than the Sun's. Also surprising was the high temperature and density of the uppermost parts of the atmosphere (raising questions about the current theories about Jupiter's formation).

    I am saying that had Uranus and Neptune been closer to the sun, they would more resemble Jupiter and Saturn in composition in part because of the accumulation of solar wind.

    Your calculations:Gas from the sun during Jupiter's existence: 1,89 x 10^26 kg - are correct assuming that solar wind has remained consistent all that time which could be a very big assumption.

    Even recently the heliosphere / heliopause was pushed back significantly by a solar storm, we can imagine that a smaller significantly smaller sphere could have an effect on collected material.
    "In some ways, the search for the heliopause is a search for a moving target because its location likely changes over time, depending upon the strength of the sun's output of plasma, or solar wind. Just as the edge of a cloud of smoke surrounding a Fourth of July sparkler alternately swells and contracts, the heliopause changes shape." - Universe today

    This is the most compelling argument that Jupiter attracts significant solar wind: "Jupiter has a huge asymmetrical magnetic field, extending past the orbit of Saturn in one direction but far less in the direction of the sun. This magnetosphere traps high levels of energetic particles far more intense than those found within earth's" -yahoo encyclopedia (I think that's where I got it).

    Jupiter 778,330,000 km distance from the sun
    Saturn 1,426,940,000 km
    That means Jupiter's effective radius that captures solar wind is very very large. (subtract these two numbers for a rough estimate)

    One would have to ask themselves if these correlations are coincidences that:
    1. The composition of Jupiter's' atmosphere is very close to that of the solar wind only a 2% difference (which could be explained if jupiter lost some of it's H early in it's history).
    2. The distance from the sun and the magnetosphere seems to correlate with the sizes of Jupiter and Saturn. Do the calculations Jupiter and Saturn's masses seem to agree with the inverse square law, and the large magnetosphere of Jupiter.
    3. If my theory was correct, it would explain exactly what we see - what you would expect to see is what we observe: Jupiter the largest and most close in composition to solar wind, saturn more dilute and uranus and neptune even more dilute (the last two possibly getting much more intersteller gas). Earth isn't a gas giant because we lose gas to a much higher degree then the gas giants.

    Having said all of this (minus what I took from the internet) I have to say that fo3 makes a good case. My goal is to make some arguments ie my conviction that Jupiter's atmosphere owes significantly to the solar wind.



    Sun: diameter: 1,390,000 km.
    mass: 1.989e30 kg
    temperature: 5800 K (surface)
    15,600,000 K (core)
    The Sun is, at present, about 70% hydrogen and 28% helium by mass (solar wind is stream of ionized hydrogen–protons and electrons–with an 8% component of helium ions and trace amounts of heavier ions - look familiar?) everything else ("metals") amounts to less than 2%. This changes slowly over time as the Sun converts hydrogen to helium in its core. The Sun's output is not entirely constant. Nor is the amount of sunspot activity. There was a period of very low sunspot activity in the latter half of the 17th century called the Maunder Minimum. It coincides with an abnormally cold period in northern Europe sometimes known as the Little Ice Age. Since the formation of the solar system the Sun's output has increased by about 40%. The Sun is about 4.5 billion years old. Since its birth it has used up about half of the hydrogen in its core. It will continue to radiate "peacefully" for another 5 billion years or so (although its luminosity will approximately double in that time).
     
    Last edited: Oct 31, 2005
  23. MacM Registered Senior Member

    Messages:
    10,104
    I was going to post this but also note that the same has been claimed for Neptune and Uranus.
     
Thread Status:
Not open for further replies.

Share This Page