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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'm entirely missing your point about programming gravity simulations (disclaimer : I have programmed a solar system simulator), and why it should explain the (according to you) rarity of nearly circular orbits. Planetary systems starting off as accretion discs with every original object have a nearly circular orbit, I don't see why planets should keep it, at least for a while.
You just got troll'd!
It's an interesting parallel with anything where you base a conclusion off a simulation. But with climate science there are very significant differences.
With our own planet we have reasonable records of how conditions changed in the past and the results of that. We've got extremely detailed recording of the current situation and the recent past. We've got firmly established science showing why those changes would cause those results. The world's climate is a little chaotic and the simulations match that state of affairs.
When modelling planetary discs, we're nowhere near as sure of the physics. We can only get decent observations of our own solar system, and there isn't a disc of dust to observe. Even the best telescopes can barely see the discs of dust around stars. We could barely detect our own solar system around another star, let alone watch it form.
Solar Systems Like Ours Are Likely To Be Rare
KentuckyFC writes
"Astronomers have discovered some 250 planetary systems beyond our own, many of them with curious properties. In particular, our theories of planet formation are challenged by 'hot Jupiters,' gas giants that orbit close to their parent stars. Current thinking is that gas giants can only form far away from stars because gas and dust simply gets blown away from the inner regions. Now astronomers have used computer simulations of the way planetary systems form to understand what is going on (abstract). It looks as if gas giants often form a long way from stars and then migrate inwards. That has implications for us: a migrating gas giant sweeps away all in its path, including rocky planets in the habitable zone. And that means that solar systems like ours are likely to be rare."
Better known as 318230.
Climatologists are now working with reasonable proxy data for the last 1300 years, not just "a few hundred point sources". These proxies are things we can measure today but that reflect past temperatures, such as sediments, growth rate of coral etc.
Growth rate of coral is one data point. You can also look at ice cores, tree rings, stalactites, isotope analysis of rocks. And sediments can refer to all kinds of interesting information, both organic and inorganic in nature.
You might be able to cast doubt on coral growth rings, but when everything is pointing in the same direction, you've got to pay attention to the most obvious reason for that.
How does anyone know what else might have affected the growth rate of coral at the time?
For one, they look at corals of the same species from around the world which grow in regions of different temperature, salinity, etc., and see how those factors are affect the coral's growth.
The other poster has a more complete answer to the broader question.
but you can't tell someone what the temperatures were without a measurement of said temperatures with an accurate temperature measurement device
That's manifestly false. Oxygen isotope proxies in ice cores are one of the prime examples of good paleothermometers, when they can be used; they depend on the rate at which heavier isotopes are transported in warmer or colder air, which is just physics. You don't need to worry about biological fractionation and such. Other proxies do good or fair jobs, depending on the type and the circumstances. Ocean proxies often do better than land proxies, since conditions are more stable. Almost all proxies are better at measuring temperature changes than absolute temperatures, though.
We have no reasonably accurate measurement of temperature before the existence of reasonably accurate measurement devices.
I'm sure you came to that conclusion from a thorough reading and analysis of the paleoproxy climate literature.
Meteorology (from Greek:meteoron, "high in the sky"; and logos, "knowledge")