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Fraser
2004-Jul-15, 05:55 AM
SUMMARY: It appears that Jupiter and Saturn formed in completely different ways, according to a new computer simulation sponsored by the Los Alamos National Laboratory. If the simulation is correct, heavy elements ended up concentrated at Saturn's heavy core, while they're spread pretty evenly around in Jupiter. This would indicate that a different process built up the two planets. The team ended up running 50,000 different scenarios based on every possible variation permitted by known astrophysics.

What do you think about this story? Post your comments below.

Apocalypse Rock
2004-Jul-15, 10:04 AM
incredible to think these worlds are so unlike each other

damienpaul
2004-Jul-15, 10:06 AM
Any insight as to the 2 mechanisms? are they analogous to something that we know of or are we speaking of a new regime of formation?

antoniseb
2004-Jul-15, 10:52 AM
Originally posted by damienpaul@Jul 15 2004, 10:06 AM
Any insight as to the 2 mechanisms?
Just guessing, I'd say Jupiter started forming like a companion star, and perhaps so did Saturn, but Jupiter made it much further before the protostellar cloud was blown away. A larger fraction of Saturn's mass [than Jupiter's] came from accretion of the protoplanetary disk.

I'd also like to point out that Jupiter is releasing energy much more by continued collapse than is Saturn. It is possible that at some point Jupiter will reach an equalibrium and cool off enough for heavy elements to start an inward fall too. [I'd expect this to be long after the sun goes Nova].

VanderL
2004-Jul-15, 12:47 PM
Although computer modelling is a very limited tool, this shows me that planet formation is a very difficult and poorly understood field of research. All the stories that have been proposed are just that, stories. Maybe they have some truth, but we just don't have enough data to feel confident about any model yet.
The way forward seems to look at other planetary systems and "compare notes". As this work has only just begun, my guess is that we need a lot more modelling before we can get the picture "just right".
In the meantime let's speculate, maybe Jupiter was always part of the solar system and Saturn is a late arrival, together with it's moons that on arrival became the innner planets: Venus, Mars, Earth and Mercury!


Cheers.

antoniseb
2004-Jul-15, 01:02 PM
Originally posted by VanderL@Jul 15 2004, 12:47 PM
we just don't have enough data to feel confident about any model yet.
I just got finished with two days of jury duty on a trial where the problem was whether there was sufficient proof of identification of a culprit. Since the trials are settled on the basis of reasonable doubt, you VanderL would be the prosecution's worst nightmare on the Jury. No real case could ever be proved sufficiently for you. :)

That being said, I agree that we will certainly be learning more about Saturn and the formation of the whole solar system. However, I'd like to see you present some idea how Saturn could have formed outside the solar system, had Mercury Venus, Earth, and Mars as moons, and could have been separated from them all in such a way that the five bodies ended up in the current orbits. To me that suggestions seems absolutely impossible... perhaps you know something I'm not seeing.

Guest
2004-Jul-15, 02:23 PM
To me that suggestion seems absolutely impossible...

In general I agree but absolutely impossile is rather strong.

Tiny
2004-Jul-15, 05:48 PM
By the way what actually makes Saturn became the most lower density planet in our solar system and Jupiter has the highest?

isferno
2004-Jul-15, 07:16 PM
hey tiny,

I know I'm a bit out of this thread now but what does your signature means???


btw, I've once done a mass-density distribution on our solar system and then Saturn didn't seem out of place concerning its weight. What Antoni stated is (sounds) probably right.

Manchurian Taikonaut
2004-Jul-15, 08:57 PM
Tiny's talk,
I assume that would be Japan language

I'm a bit rusty with Nippon but here goes



Ohayo - usually means Mornin'

minnasan watashi wa newbie desu -Mr minna I'm a new person

yoroshiku onegai itashimasu! - a kind of introduction or typical Japan greeting like hello, pleased to meet you, or excuse me please give me your attention thanks very much..that kind of talk

Greg
2004-Jul-16, 03:23 AM
Saturn's moon Phoebe may offer some clues to Saturn's origin. It is the first major gas giant in the outer solar system, with moons that reflect a population of objects from the central part of the solar system (Mars/Jupiter/asteroids) and outer solar system (kuiper belt like objects) like Phoebe.

VanderL
2004-Jul-16, 08:26 AM
Ok, and let's add to that the axial tilt of the Earth, Saturn and Mars; they are all very close to each other and different from the rest.
Saturn could have been a brown dwarf star with it's own planets (Mars Earth and maybe Venus and Mercury), captured by the Sun. That would have been the time of great catastrophic occurences that sent Earth, Mars and Venus into their current orbits. Mars changed into a barren world stripped of it's surface, Earth suffered it's ice ages and Venus turned into a molten chunk of lava.
More later,

Cheers.

Tinaa
2004-Jul-16, 02:38 PM
Saturn isn't even close to being big enough to be a brown dwarf. I thought you had quit with the electric universe junk VanderL.

VanderL
2004-Jul-16, 03:05 PM
Saturn isn't even close to being big enough to be a brown dwarf.

Are you absolutely sure about that? Brown dwarves were not supposed flare either, but since they can the lower limit has been adjusted, so maybe wedon't yet know what the lower limit fpr a brown dwarf is, and maybe we don't know what a brown dwarf ir either. As I said I was speculating, if you think I quit the electric universe "junk" I suggest you read the debunking page again. I still think it an interesting concept.

Cheers.

antoniseb
2004-Jul-16, 04:17 PM
Originally posted by VanderL@Jul 16 2004, 03:05 PM
Are you absolutely sure about that? Brown dwarves were not supposed flare either, but since they can the lower limit has been adjusted, so maybe wedon't yet know what the lower limit fpr a brown dwarf is, and maybe we don't know what a brown dwarf ir either.
The difficulty in being sure [or not] is that we have a loose definition of a brown dwarf, vs. a gas-giant planet. Neither one converts Hydrogen to Helium. Any energy they release comes from the slow collapse and conversion of gravitational potential energy. This can come as magnetic flares, as well as simple IR and radio radiation.

In common usage, we say that Brown Dwarfs form as stars do, and planets form largely from the proto-planetary disks, but clearly there is some middle ground where both processes could have contributed to the creation of the object. I think it is likely that Jupiter and Saturn fit this category. However, the upper limit mass of a brown dwarf [as opposed to a minimal red dwarf] seems to be fairly well defined somewhere between 65 to 75 Jupiter masses. At the high end of this range the object may briefly have some fusion process until its Lithium is consumed. These Lithium consumers are usually still called Brown Dwarfs.

What is completely a question of semantics is what is the lower limit of the size of a brown dwarf. I can imagine a scenario in which an object following the star forming process could be interupted, leaving an object smaller than Uranus or Neptune that still has the self gravity to survive as a celestial free-floater for the age of the universe so far or longer. Is such an object a brown dwarf? It is NOT a planet. Perhaps we need a new name for such an object, like a Cold Fuzz-Ball. or something like that.

None-the-less, I believe that the chemistry of Saturn tells us that it had a lot of material from the protoplanetary disk, and we are safe in calling it a planet.

StarLab
2004-Jul-16, 11:54 PM
I thought you had quit with the electric universe junk VanderL.
Hmm...what is this "electric universe" junk you speak of? I'd like to check it out and read it for myself...then I can judge whether I will agree or disagree...

Guest
2004-Jul-17, 12:01 AM
http://www.universetoday.com/forum/index.p...wtopic=1919&hl= (http://www.universetoday.com/forum/index.php?showtopic=1919&hl=)

Here ya go.

Oops this was me...Tinaa

StarLab
2004-Jul-17, 03:17 AM
Yeah, I read it, and I didn't trust that pro-electric universe guy after reading the first paragraph, because it was written SOOOO unprofessionally, what with the catchy, quoted words. The guy was trying to put a spunk on his article. I'd throw up before finishing it. Maybe if somebody else wrote a pro I'd read it.

Guest
2004-Aug-13, 10:59 PM
"The team ended up running 50,000 different scenarios based
on every possible variation permitted by known astrophysics."

This indicates improper basics of the current astrosphysics.