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Originally Posted by Jerry
A decrease in the ‘inertial capacity’ of the system leads to an underestimate of mass. Let me use electronics to illustrate the concept: I can hang my Christmas lights up on any house in the valley and get a good estimate of the distance from the luminosity. But if I plugged them into my house and ran a long extension cord, my estimate would be way off if I did not include the line loss in the calculation. When we launch a probe away from the Sun, As the mass of the system decreases, so does the apparent mass of the rocket. No, this is not Newton and Einstein, and we know it.
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Where does the mass go? If I'm following you right, a spacecraft travelling in a straight line between the Sun and Neptune should see the Sun's mass decrease and Neptune's mass increase. What happens to the Sun's mass? Where does Neptune's increased mass come from?
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Originally Posted by Jerry
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Originally Posted by Taibak
The six minute discrepancy between the two sets of measurements of Saturn's rotation isn't anything to get too worked up about. It's only a discrepancy of 1% and well within acceptable errors, particularly when you consider that the instruments on Cassini are some 20+ years more advanced than the Voyagers'.
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Sure it is. Yes, radar imaging has improved, but you can’t tell me we couldn’t nail an orbital period any better than 1% with Voyager or Pioneer data, and in the same breath tell me the same data can be accurately used to calculate the masses of the moons and planets! This is exactly the scale of error we are looking at in the Pioneer anomally. |
I still don't see the problem there. Saturn's rotational period is very difficult to measure since it doesn't have any reference points on it surface (or even a solid surface for that matter). With that in mind, I'd consider a 1% error pretty good. I'd also consider 1% to be an acceptible error in measurements of the planet's mass.
Also, different data was used to measure the two properties. Like you said, the orbital speeds of Saturn's moons and the deflections of various probes were used to measure it's mass. You can't use those to measure its rotation.
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Originally Posted by Jerry
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Originally Posted by Taibak
Molecular bonding has little to do with how a planet holds together.
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True for big planets, not for little ones. Phoebe and many of the other moons of Saturn are not round. There is not enough gravitational energy to shape them. Phoebe is pockmarked with craters, indicating, unless you are a NWC, a great deal of age. If Phoebe were made out of Ice, one high velocity zap from anything bigger than a bagel would pulverize it. Molecular bonding as we know it? Or some unknown icey Saturn glue? |
No, it's still gravitation holding them together. They just don't have enough gravity to pull themselves round. Eros, for example, is a bundle of rocks held together by their collective gravity.
As for Phoebe, it's not as unstable as you think. It's big enough that it would take a massive impact to shatter it. A smaller object would gouge out a crater, but you'd need a LOT of energy to break it apart completely.
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Originally Posted by Jerry
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Originally Posted by Taibak
Neptune doesn't look anything like the inner planets. It's a honkin' big ball of hydrogen and ammonia. The inner planets are, essentially, rocks and iron. Its density is much less than the Earth because it's a ball of gas instead of a ball of rock with a creamy iron center.
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Much of this is speculation, based upon the data from the inner stellar probes: before the fly byes, we had every reason to believe Neptune was not very different from inner planets. |
Irrelevant. Now that we've sent probes by, we know that it is.
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Originally Posted by Jerry
The moons of Neptune don’t look like hydrogen and ammonia, and they hardly could be, but they have nearly the same density as Neptune.
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Different materials can have similar densities. Moreover, we think Neptune has a solid core under all that gas.
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Originally Posted by Jerry
Geophysicists are at a complete loss to explain Europia.
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What are they at a loss to explain?
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Originally Posted by Jerry
A better interpretation of what we see is that 1% error in the orbital rotation of Saturn is real and we don’t know the true accelerations of the probes near the great planets. I really think Cassini will help straighten this all out, but only if we look at the data with fewer preconceptions.
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Nah. The simplest and best interpretation is that
Voyager's measurements were only accurate to within 1%. That's still perfectly good data.
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Originally Posted by Jerry
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Originally Posted by Taibak
Neptune's satellites also look nothing like the inner planets. Amongst other things, you don't find volcanoes that produce liquid nitrogen in this part of the Solar System. Their density is much less than the Earth's simply because they have different compositions - most notably, they don't have a large iron core like the Earth does.
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Again, this interpretation is based upon the mass calculations. |
It's also based on photos and spectral data. We know that Triton, for instance, is covered in frozen methane.
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Originally Posted by Jerry
The theory that there is no iron core is based upon the assumption an iron core always creates a linear magnetic field – there currently no consensus model that assigns causality to this prediction. Mars definitely has an Iron core, but an extremely weak magnetic field.
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Actually, you need a spinning, liquid iron core to produce the magnetic field. For whatever reason, this dynamo effect is no longer operating on Mars. The core may very well have cooled. The same is probably true for Mercury and Venus, implying that their cores are smaller than the Earth's.
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Originally Posted by Jerry
This is one case where the chemists should be shaking the astro-geophysicists by the collar and running some sanity checks! Liquid nitrogen does not erupt and solidify into visible flows. Water would not flow from a liquid nitrogen volcano either. These scenarios are like climbing up a glacier and expecting to find a volcano cone.
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Except
Voyager II observed these volcanoes directly during its Triton flyby.
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Originally Posted by Jerry
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Originally Posted by Maksutov
The final NASA report concluded the most probable cause of the failure was the generation of spurious signals when the lander legs were deployed during descent. The spurious signals gave a false indication that the spacecraft had landed, resulting in a premature shutdown of the engines and the destruction of the lander when it crashed on Mars.
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Dysfunctional landing pads is just the kind of thing I am looking for! Do they know the rockets shut down before it hit, or is this just a guess because they know it hit too hard? How do we know the craft was not accelerating much faster than planned, and this created enough resistive air flow to trip the pad sensors? |
How does a systems failure support your theory? All NASA seems to be saying is that something went wrong on the spacecraft.
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Originally Posted by Jerry
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Originally Posted by Maksutov
Concerning your foray into number tweaking and numerology, the coincidences remind me of Bode's "Law".
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Me too. The jury is still out on Bode's law and frankly, I do think it is a function of resonant effects not so different from the weaving in the rings of saturn. |
Well, no. If Bode's law had any validity, it would predict the orbit of Neptune.