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Is Jupiter Dissolving Its Rocky Core?
sciencehabit writes "Jupiter is the victim of its own success. Sophisticated new calculations indicate that our solar system's largest planet, which weighs more than twice as much as all of the others put together, has destroyed part of its central core. The culprit is the very hydrogen and helium that made Jupiter a gas giant, when the core's gravity attracted these elements as the planet formed. The finding suggests that the most massive extrasolar planets have no cores at all."
Just need to toss in several hundred thousand black monoliths, and we'll have a new star in the firmament.
Dark Reflection
Alas our current US government has sought to sink our space program so it will need to wait for another day.
You mean when they cancelled shuttle-derived boondoggle money pits?
That's actually the best way to *increase* the resources available to do real the planetary science you're talking about.
As far as I know, that question was still open to at least some debate. It's hypothesized that there should be a solid core based on the mineral composition and some simulations, but I don't believe there's any direct evidence of it, at least until the mission (mentioned in the article) to measure its gravitational field with an orbiting probe reaches it.
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
Dissolving a solid into a liquid doesn't change it's mass.
People in cars cause accidents....accidents in cars cause people
No. It is estimated by the orbits of it's satellites, using Kepler's laws. If you know the period, eccentricity, and size of a satellite's orbit, you can work out the mass of the object that the satellite is orbitting. It has nothing to do with how much of that object is solid.
When our name is on the back of your car, we're behind you all the way!
Next thing you'll tell me is that a pound of feathers weighs as much of a pound of bricks!
This is not the funny you're looking for.
We know A LOT about the cores of the planets in the solar system from extensive study (including molten, material and other stuff that can be determined from external study). It appears you are talking about examining extrasolar planets. We don't have the capability, and it's doubtful we will, at least in our lifetime. Voyager1 just left the solar system and it's moving at ~35k MPH and it was launched in the 70's, most of the people that designed it are retired or dead and Voyager1 will be dead long before it reaches any other star.
The Magnetosphere helps keep solar winds from stripping our atmosphere away from us.
What maintains our atmosphere is the magnetic field generated by the liquid mantle rotating around the core. The magnetic field deflects the solar wind which would blow it off. It's thought by some that Mars lost it's atmosphere and surface water when the liquid mantle cooled and solidified. Mars has no magnetic field.
I knew the core was supposed to be the cause of our magnetosphere
That's a large part of the answer right there! The magnetosphere acts as a shield to keep a lot of harmful particles from the solar wind away, things which would work to strip away the atmosphere. Mars is an example of what can happen to planets that lack this. (Obviously, Mars' lower gravity works against it in this regard as well)
http://science.nasa.gov/science-news/science-at-nasa/2001/ast31jan_1/
OtakuBooty.com: Smart, funny, sexy nerds.
Clearly DeBeers needs to hire you to lead their next ad campaign, "Diamonds are quite long-lasting relative to other materials, though they will eventually decay".
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
You do realize that liquid rock has the exact same mass as solid, right?
That's mostly correct, but as heat is a form of energy and E=mc^2, a rock changed into liquid state would mean that it weighs oh-so-slightly more. For some napkin calculations: the specific heat of iron (at 273 K) is 0.45 J/(K g) meaning that if we had a thousand tons of iron (1E9 g) and increased the temperature 1000 K then the increase of mass would be: 0.45*1E9*1000/(3E8)^2 = 5E-3 g. All that mass and energy for a full 5 milligrams, which is why it's mostly negligible
Disclaimer: I know that the specific heat changes (quite a bit) with temperature but I wanted to keep the example simple.
I'm glad to see the shuttle no longer leeching the life out of NASA, but you have to know the cuts go well beyond that. It's not like ditching the shuttle actually freed up more funds for NASA. Bankers need their bonuses far more than we need to do basic science, after all.
Then how does Venus, which has almost no magnetic field manage to retain a very dense atmosphere?
The world's burning. Moped Jesus spotted on I50. Details at 11.
Look at the composition.
Venus's atmosphere is very low in certain molecules.
Nitrogen.
Elemental oxygen.
Water vapor
Et al.
What it is high in, are comparatively dense gasses.
Sulfuric acid
Carbon dioxide
Etc.
The solar wind is highly energetic, but is comprised of small atomic mass particles. They lack the kinetic energy to strip away very heavy gasses with strong intermolecular forces. Water, while having strong intermolecular forces, is a very light molecule, and the high energy particles have sufficient energy to break the single covalent bonds that hold it together. This means the cosmic wind rips it apart, and then scours it out into space. Sulfuric acid and cabron dioxide, on the other hand, are very heavy, gravitate deeper into the gravity well, and in the case of co2, have double covalent bonds that are quite powerful. The solar wind doesn't have enough oomph to rip it apart, and the molecules are too heavy to easily blow away.
Mar's armosphere is actually sabotaged by a weak and incomplete magnetic field. It has many small and weak diploles extending from the surface. Under the influence of the solar wind, this actually pinches off large chunks of atmosphere during heavy flares from the sun. This is why mars has such a pronounced atmospheric loss, compared to venus, which doesn't have any discernable mgnetic field at all. If you note, the atmosphere mars does have is comprised of what? Co2.
To expand this a little -
Through fusion, lighter elements like hydrogen and lithium may be combined (nuclear). This process will provide a net energy output up to "iron."
Through fission, heavier elements may be disassociated (nuclear). This process will provide net energy output down to "iron."
When all you have left is iron, making something else via nuclear methods requires the addition of energy. Thus, "everything decays to iron" represents a lowest energy state from a nuclear perspective. But don't worry, the heat death of the universe won't happen for a long while.
Jupiter is no longer hard core.
We'll send special ships to the center of the earth with large hydrogen bombs that will restart the rotation of the core itself.
This is all documented here:
http://en.wikipedia.org/wiki/The_Core
You were mistaken. Which is odd, since memory shouldn't be a problem for you
> GO POUND SAND
The pound sand doesn't appear to have an entrance.
You are not a brain: http://books.google.com/books?id=2oV61CeDx-YC
Mar's
Never has an apostrophe made me so sad.
Neither. As the sun gets older, it gets brighter (according to wikipedia, about an 10% increase in luminosity every billion years). At some point there will be no more liquid water available because the surface of our planet is too hot. This will happen long before the sun turns into an actual red giant, which in turn will happen long before it runs out of fuel.