Ahh, I'm finally starting to see what your trying to say.

But than one has to wonder why the mass of Huygens would get larger?
Just because Huygens has entered a 'Higher G' doesnt mean that the probe is going to accuire more mass. Where would the extra mass come from?

Any chance this is a term goof with mass and weight? Weight would increase, not mass.

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I'm not completely heartless, the doctor who removed it told me he'd never be able to get it all.

Doodler, you're right, it's a confusion of terms: 'mass' sometimes used for 'weight' in common usage. In local G (if this is actually true for Saturn) the weight would be 10x, except that the planetary 'weight' (we never put these on a scale to measure their kg) counters with being 1/10th of our (Earth G) estimate. So the net result is a wash, and probe acted in normal expected manner upon reentry.

I don't know for sure that the probe would not experience a somewhat greater acceleration towards Titan, not sure about that. I do think the molecular atmosphere density should be affected by greater G since all the molecules exhibit this G personally up close as they bump into each other... I think... :-?

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Caveat Lector. Experimentum summus judex...

I have absolutely no confusion, force = mass x acceleration and according to the SI system force has dimensions of (kg.m)/s^2 or Newtons (N)

Mass is an intrinsic property, weight is dependant on local g. Astronauts on the moon may have weighed 1/6th. of their weight on earth but their body mass was still the same (all other things being equal)

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By asking questions we sometimes get the wrong answers, from wrong answers we learn to ask the right questions.

[quote="Fortis"]The 'trace' I am talking about (wiggle wiggle), is how quickly the Jovian atmosphere settled down as if nothing happened. We have this big old 'Eye of a Storm' that has existed on Jupiter for a minimum of several centuries, but the impact of Levi-Shoe on the atmosphere of Jupiter disappeared within a few rotations. I think most the texts written today make it clear Jupiter's eye is not likely to be a hurricane-like storm, but something more closely associated with Jupiter's magnetic field. (If they don't, they should.)

http://www.jpl.nasa.gov/sl9/back1.html

(I'm not knocking our inability to predict what would happen when the comet spread itself across Jupiter - any educated guess was just that.)

I have read, and I wish I could find a good source, that the turbulance in Jupiter's atmosphere does not seem to generate the tight eddies that disrupt laminar flow and should lead to the disappearance of the eye, like we would expect with similar densities and velocities on Earth, and this is difficult to model and understand. I think these are critical observations indicating just how non-Newtonian the universe might be.

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jwj

It's ok not to know.

Ok, let's make this absolutely crystal clear:

Take an object with a mass of 1kg (measured on Earth), and place it in orbit around the sun at the distance of Saturn's orbit. Let's say that it is on the opposite side of the sun from Saturn, so it's just floating in space basically unaffected by Saturn's gravity.

What would you measure the object's mass to be, under the conditions above?

Jerry, please do not confuse non-Newtonian fluids (eg. 'silly putty' or thixotropic paint) with a non-Newtonian solar system. Newton was well aware that real fluids didn't behave in his ideal manner.

I do actually have an ATM conjecture of my own regarding the comet impacts and that long term atmosphere. Is the recently found polar 'hot spot' in fact a remnant of those collisions? If there's sufficient interest in the idea then we could maybe have another thread on it because I don't want to dilute this thread.

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By asking questions we sometimes get the wrong answers, from wrong answers we learn to ask the right questions.

True, but the atmospheric of Jupiter should be roughly as close to ideal as the atmosphere of Earth...at least as deeply as we can observe it, the Reynolds numbers should be in the same ballpark.
Good point - let's do that...

edit - typo

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jwj

It's ok not to know.

Weight doesn't change the underlying equation, though. Gravity is a function of mass. Understand too, that even though gravity is different based on a planet's mass, and the relative distance from the planet, the level of gravity produced by that mass doesn't fluctuate.

Gravity pulls an object as a function of its mass, not its weight. This applies even on Earth. If anything, objects actually slow as they encounter thicker atmosphere closer to the surface. A skydiver on Earth jumping from 80,000 feet (and there have been lunatics who've done this) will reach nearly Mach 1 in the early part of the fall, but slow to barely more than 120mph by the time they reach the lower altitudes under 10,000 feet because of air density. Titan would be no different.

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I'm not completely heartless, the doctor who removed it told me he'd never be able to get it all.

I agree… This would put a pretty strict upper limit on the increase in G, if the mass of the probe really changed. Also, plain old acceleration=force/mass would preclude a variation in G higher than a few percent, as it would dramatically alter the effects of course correction burns, reaction control systems, and spin stabilization.

For a variable G to work, the mass has to be constant. If the attractive force of gravity increases proportionally to the distance from the sun, the force produced between two masses at Saturn is equivalent to that of two higher masses at Earth. All other observations related to Mass would not change-- namely F=M*A.

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Do try not to take me too seriously.

Placing it in orbit changes the dynamics, since orbital momentum offsets gravitational pull, so not the same as falling into Titan, per my understanding.


I figure Titan's G region this way: Mass is fixed per our estimate of G, except that the planetary 'weight' (we never put these on a scale to measure their kg) counters with being 1/10th of our (Earth G) estimate. So the net result is a wash, and probe acted in normal expected manner upon reentry.

This is significant because of the 'masking effect' of having estimated mass using a universally constant G.

Of course, if G is a universal constant, then there is no need to look further. This exercise is to show how G may be different, and that we should make some effort to look for this.
As pointed out: However, this is correct ONLY under the current acceptance of G being a universal constant.

Now, if G is NOT constant, what happens to "weight" under that scenario? On Earth we had mass and weight figured in "kilograms". What I am suggesting is that the same kilograms we use on Earth need to be modified elsewhere in local G terms of it is not universal constant. For example, Huygens's mass of 319 kg, which is also its weight on Earth, would have to be reclassified on Titan in its local G, so if weighed there in kg(Titan) it would be 319 kg(Titan), which translates into kg(Earth) as ~3190 kg(Earth). Is this logical to you'all, if G is 10x times that of Earth? Is this reason enough to want to find out if Titan/Saturn G is greater than on Earth, though evidence to this had been 'masked' from our point of view? Everything worked just fine with a universal G, so why look further? [-X That, IMHO, is where we had been. Now, can we go to the next step and measure G at different orbital regions of our solar system, and by extension in deep space? I think we can, and very easily, by testing for "inertial mass" out there. Because of Equivalence principle, our inertial mass readings would yield for us what is local G. :roll:

That brings us back to F = ma. Can we use this to measure for inertial mass by accelerating mass? If F turns out to be higher than our Earth based model to move mass by a, then of necessity inertial mass is greater, which translates into a higher G region. Would this test be doable, or meaningful, in your estimation?

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Caveat Lector. Experimentum summus judex...

It has been done, inumerably with every probe that has left the surface of the earth. This includes all balistics, i.e.: cannon fire.
In other words: Been there done that...

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Feynman
>~~~~<
Science is a way of trying not to fool yourself. The first principle is that you must not fool yourself, and you are the easiest person to fool.

Religion is a culture of faith; science is a culture of doubt.

So in other words, you can't or won't answer the very simple question of whether mass varies with distance from the sun.

A couple of weeks ago, you said this:

Just a couple of days ago, you said this:

All I'm asking is that you clarify these statements.

You're ignoring my points:

1. M for planets is an Earth estimate.
2. G is measured from Earth.
3. m is fixed mass of probe traveling.
4. fixed mass m is RELATIVE to M estimate in terms of G.
5. If G is NOT same as on Earth, then m as a relation of M changes.

I am not ignoring your questions. I suspect you are having difficulty with the concepts involved.

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Caveat Lector. Experimentum summus judex...

You have to understand that the Mass of an object is determined independent of gravity, this is why the most basic of mass scales aren't gravity scales, they are fulcrum balance scales. Object mass is the same whether its on Titan, Earth, or in deep space. That's where you're slipping. Weight is a function of Mass and Gravity, but for the purposes of any velocity or acceleration computations, its the Mass value that applies.

Gravity is a measure of the attractive force of one mass to another. Even small objects like Huygens have a measure of gravity to them. The pull of gravity varies ONLY by distance. That does not make gravity variable though, given a body of known mass, the force of gravity at any distance can be effectively computed. Take the Sun on one hand, and a 1 Solar Mass black hole on the other. The surface gravity of each is wildly different, BUT the pulling force of gravity in each is identical. A black hole's surface gravity is higher because the density of the material is higher, and the object is much smaller, allowing another object to experience the pull of gravity to a greater extent at a closer proximity than the sun. But taken in the other direction, the Earth would experience no change at all from 93 million miles away orbiting either object, because the gravity is equal.

To revisit this point, you must understand that there's a reason this is called "artificial" gravity. Gravity is measured in terms of acceleration, because the pulling force of an object's gravity is acting upon you constantly. If you were to be at rest (not in motion) above the Earth's surface, it would begin pulling you towards it at a predictable rate determined by your distance from the surface, and that rate would increase as you came closer, both because the acceleration is adding to your velocity, and the pull of gravity is increasing the rate acceleration as you move deeper into the gravity well. Its the effect two bodies have on one another and the rate at which those bodies will tend to want to collide, but, there is no inherent motion in either attractor.

The apparent 'gravity' felt in a moving object is the result of the motion caused by the expenditure of energy to move the object. In this case, the F variable is the thrust energy of the object, not its G. Gravity requires no expenditure of energy to have its effect, that's the difference.

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I'm not completely heartless, the doctor who removed it told me he'd never be able to get it all.

I guess the real bottom line you need to understand is that mass and weight are completely separate entities. Changing G, or even the value of G, doesn't change the mass. Gravity is the force of attraction of a body at rest. A body in motion would also have a force equal to its velocity, but its not gravity.

We relate a fixed value of G relative to M, because generations of observations have determined that objects of a given mass have a known and predictable effect on other objects. Satellites orbit the Earth under this prinicple, satellites and manned spacecraft have orbited the Moon under this principle. Every body in this solar system that has had something put into orbit around it has operated under the principle that the local force of gravity is predictable given the mass and the distance from the center of mass for the body in question. Variable gravity is present in some form in places like the Moon, where the mass of the object isn't equally distributed within its volume, but that variation of G is predictable if the variation of the distribution of mass is known. The value of G relative to M does not change, it is still predictable.

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I'm not completely heartless, the doctor who removed it told me he'd never be able to get it all.