Slashdot Mirror
New Study Shows Solar System Is Uncommon
Iddo Genuth writes "Research conducted by a team of North American scientists shows our solar system is special, contrary to the accepted theory that it is an average planetary system. Using computer simulations to follow the development of planets, it was shown that very specific conditions are needed for a proto-stellar disk to evolve into a solar system-like planetary system. The simulations show that in most cases either no planets are created, or planets are formed and then migrate towards the disk center and acquire highly elliptical orbits." The research was published in Science magazine; here's the paper on ArXiv (PDF).
I wouldn't read it like that
Space is still the big unknown. If this "shows' anything, it seems more probable that this 'shows' that the simulations aren't complete enough yet.
If they would deduce this from actual statistical data, it would show something, but deducing this from simulation seems a a bit to trustful to the current state of science if you ask me
If even one thousandth of one percent of stars form solar systems similar to this one, that would still be quite significant.
I have to ask: Under which solar formation model was this conclusion drawn? Because from what I understand, there are a number of competing theories, none of which have come anywhere near being conclusively proven. I actually studied under the creator of one of the models, Andrew Prentice, and was in a position to watch as the predictions of various hypotheses were proven true or false. We've got a long way to go in the field, from what I understand.
The question isn't whether it is special, but HOW special. And TFS failed to even give a fake number to calm us data freaks down.
I agree. Basing conclusions off simulation models is risky, mainly considered how in the domain of planetary simulations, well established models get entirely questioned every once in a while.
And at this point even actual statistical data is hard to use to conclude anything about our solar system, because of our limited observation capabilities, what we know has a heavy statistical bias.
You just got troll'd!
I dislike pointing this out, but that's an interesting parallel with climate science. I remember hearing recently (on Slashdot?) that climate models primarily base their data on one or two sources that, if altered slightly, would throw the simulations pretty severely, one way *or* the other.
Have you actually tried running your simulation for (simulated) four billion years? Don't you think that over a long period of time the various objects would act on one another to even their orbits out? That's the way I understood our current setup arose.
Research conducted by a team of North American scientist shows our solar system is special
... therefore, God created this solar system specially for man, which is the center of the Universe.
I love this based-on-new-studies "science".
Just because we can't see (yet) any other kinds of solar systems, doesn't necessarily mean ours is "special" !
Hehe. Yes, if the computer models show something other than what we already know to be true (that we can't possibly be special...because you know what that would mean), then their models must be incomplete and reworked until such time as they agree with what we know to be true.
... currently?
It's just "educated guessing", nothing more.
Add to that a lot of speculation about planetary formation and who can have any degree of certainty about where our solar system sits in the scheme of things.
We need to observe many more planetary systems before we have a clue.
Art is the mathematics of emotion
Given the limits of our technology to detect extrasolar planets, how are "they" able to make this conclusion, especially when it is based on simulation? We are able to detect Jupiter-sized planets right now, yes? How about we wait for some better technology that can detect Earth-sized planets more accurately before we go rushing to the idea that we are "special". While the that idea intrigues me, it would certainly make the galaxy a more boring place.
Bearded Dragon
They performed 100 simulations and got a result compatible with our solar system. If only 1% of solar systems ended up similar to ours with planets, there would still be tremendous number of similar solar systems out there. I don't think this is anything to be worried about.
OK, I think I see your reasoning, basically increased entropy in accordance with thermodynamics, right? I'm not saying you're wrong, I'm just saying that you might be misapplying the laws in this specific case.
For example, the earth and the moon. The moon at one point had a certain rotational speed (on its own axis) and another speed for its orbit around the earth. The two are now exactly (AFAIK, or very close) the same.
I believe your argument, if applied, would say that the chances of the day-length matching the year-length would be very small, that it was the "special case" and that the longer you leave it, the more likely it would be that the orbits would not be synchronous.
However, due to "tidal locking" (see wikipedia) the moon would indeed eventually tend to have a synchronous orbit.
All I'm saying is, perhaps there is some affect such as this in effect when it comes to near-circular orbits etc.
Try modelling tidal effects in your simulation. These tend to drive orbits towards the circular over time.
Real Daleks don't climb stairs - they level the building.
The summary != TFA. Surprise!
"Due to the complexity of the developing system, which includes the disk-planet and planet-planet interactions described, the simulations resulted in random systems. Nevertheless, two dominant cases were detected.
In a disk with low mass and high viscosity, the gas in the disk is removed before a planet can form, resulting in a system that has only rocky, icy bodies. At the other end, in a disk with high mass and low viscosity, planets are formed but are pulled towards the center of the system and acquire highly elliptical orbits around the star.
In the intermediate case, planets form but undergo only modest migration towards the star and their orbits don't become as elliptical. This seems to be the case of the solar system. The simulation showed that this case is realized in a small number of systems, meaning the solar system does not resemble most planetary systems. "
The report is saying that along a spectrum of possibilities, there are a number which produce results different than our system.
1) It says nothing about the real life DISTRIBUTION of these alternatives. If only a narrow band of X values produce the results you want, this isn't necessarily a problem if you're in the high point of a steep bell curve. Look at a H-R diagram - there are clearly 'sweet spots' in stellar development across the range of possibilities. Nothing says planetary development is any different.
2) This of course means little. There is no evidence either way to suggest that life (which is the point of looking for solar systems - I don't think we just have some weird fetish for similar solar systems) can or can't develop on those alternate results. Hell, we may find that solar systems with nearly circular orbits are rare but that's good because they produce the Galaxy's retarded civilizations, and everyone ELSE out there is laughing/pitying us.
FWIW run your own particle/gravity simulation, and find the same results yourself: http://www.spore.com/comm/prototypes. It's awesome, and finally a use for that uber-mega-cpu you just bought.
-Styopa