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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."
I didn't RTFA, but I will when I get home.
But on the surface it seems more to me that they're just saying that solar systems have a life cycle that is marked by the location of gas giants. I don't really think that means that our setup is rare.
But if I am misinterpreting the blurb and that is what they're proposing I would still say we need to hold our horses on any real judgement. We've found these solar systems because our current method of seeking these solar systems out is going to be more likely to find this kind of activity as opposed to what we have here at home. I think we're jumping the gun a bit on this one. I say let them work it out for a couple of more decades and even then we should be a bit more cautious about such sweeping statements.
Dedicated Cthulhu Cultist since 4523 BC.
when they have capability of detecting Earth > Venus > Mars size planets
they don't have much data do they to base their theory on?
Actual data is highly biased towards gas giants in close orbits because that's what's easy to detect.
Simulations like these don't have sufficient real-world data to make any reasonable statements about what kinds of solar systems are likely.
Also, "rare" is a relative term; if 1% of all planetary systems contain a habitable planet, there would be a lot of them and they'd be rather closely spaced.
Really, in terms of the universe, EVERYTHING is rare. Galaxies are rare. Stars are rare. Matter is rare. About the only thing that isn't rare is space itself. Draw a line segment across the universe, make it trillions of miles long. How many atoms did you actually touch with that line?
ADVENTURERS! - ANTIHERO FOR HIRE - CARDMASTER CONFLICT
Do you honestly believe they didn't take that factor into account ?
Astronomers would be the firsts to enjoy a theory that says that We Are Not Likely To Be Alone. Be sure that if this discovery is peer-reviewed, all these arguments have already been opposed.
The Wise adapts himself to the world. The Fool adapts the world to himself. Therefore, all progress depends on the Fool.
Whatever... this is naval gazing and conjecture, no more credible than Intelligent Design. These guys have a few data points, they create a highly convoluted system that seems to account for their data points, then the moment they get more data, they start over. Again and again.
A good critical thinker should know when to say "We don't have a fucking clue" if they want to be taken seriously. But then, it's all about money, isn't it?
-1 Uncomfortable Truth
This is a big deal, because back when we only knew about our solar system, we formed theories to explain it. These theories imply that we wouldn't find many cases of large gas giants near suns. The current observations falsify these theories. We don't have to have a total picture of every planet in the vicinity to know that; detecting too many large planets is sufficient.
Your issue of our ability to detect only these types of planets is totally irrelevant to the main point about our theories making now-falsified predictions... which makes your accusation that others are misinformed about science that much more ironic. Perhaps you should be sure your ducks are in a row before accusing others of not understanding science.
Best estimates put us at 30 billion planetary systems in the Milky Way galaxy alone. If only 0.0001% of those planetary systems holds an Earth-like planet capable of sustaining life, that's 3 million Earths, just in the Milky Way. Now consider that figure holds for all galaxies. A conservative estimate from Nasa's scientists puts the universe at 125 billion galaxies. That's 3 trillion 750 billion planetary systems. If only 0.0001% of those systems are host to life-sustaining Earth-like worlds, that's 375 billion Earths in the universe. Perhaps that is rare, considering how stupidly big our universe is... but that is still a hell of a lot of Earths.
It seems like every other day there's a new article/paper/prognostication conclusively demonstrating the rarity/abundance of Earth-like planets/systems. Honestly, at this point I'm just going to hold my judgment until I can get out there and see for myself.
Yes, our theories were WAY off. No one predicted that these hot Jupiters were out there. Now they make up almost all of the planets we've detected to date. The point I was trying to make is that we can't detect solar systems like ours yet. Unless MAYBE it was in the alpha centaurus system and then MAYBE if it's Jupiter equivalent were to pass in front of one of the stars.
Please, tell me how many exosolar planets we've found with orbital periods greater than 365 days? How about 4000+ days like Jupiter?
Talking about how rare we are, without even another example, because we lack the ability, is just another theory that will fall - kinda like the planet formation theories that lacked the ability to predict "hot Jupiters". Now they have gone to the other extreme and theorized that EVERY solar system starts out with hot Jupiters. You know, because that is all we can presently detect.
How is that irrelevant? It's EXACTLY the "To a hammer, all looks like a nail" analogy I started with. Since that is all we have the ability to find at present, now all solar systems must start out that way?!?!?!?
This is the same mistake all the theorists made to start with, since all we had was our own solar system to base this upon. Now they have gone exactly the opposite way in their theories which is repeating the same mistake they initially made.
Yes, you adapt your theories based upon more and more observational data. But when you KNOW your observational data is limited to one subset of possible outcomes(which makes our own solar system damn near impossible to form) and you claim "victory", that's just very illogical to me.
Prof. Farnsworth - "Oh a lesson in not changing history from Mr I'm-My-Own-Grandpa!"
But Science is about proving things, not suggesting every possible idea and disproving them one by one.
Where on Earth did you get that idea? One of the first things you learn about science is that it doesn't prove anything, only disprove. The scientific method is a three step process:
You observe phenomenon, create a theory that explains it and makes some predictions and then test these predictions. If the observations don't match the predictions you either discard or refine the theory. If they do, then you keep it around until you find some new observations that don't match up with the predictions.
The reason creationism is not science is that it makes no testable predictions. Whether it is true or not can not be tested and so is an irrelevant question to science.
I am TheRaven on Soylent News
Science is about proving things, not suggesting every possible idea and disproving them one by one.
Exactly the opposite is true. Science is never about proving anything. Mill's "black swan" analogy illustrates how we can make reasonable inferences and still be wrong because nature is otherwise. Every swan you've ever seen is white, so you think "all swans are white, and certainly none are black!" Upon discovering that some swans are black, the rule is not so fast. It might be tempting to claim that no swans are plaid, but even this is not provable. Nature could turn out to be different than it appears.
Creation Science can throw out some sticky questions and make some points that are hard to disprove.
They cannot be disproven, even in principle, and this is the last bastion of special creationists; they know nobody can prove so much as "the world wasn't created 5 minutes ago, with all its state and photons in flight and past memories in place", and they prey on people who think this is a failure of science. Doing science is about making wise inferences, and claiming special creation is not wise inference because empirical evidence detracts from (but does not *disprove*!) it.
established scientific ideas are SUPPOSED to be dogma.
No, scientific ideas are supposed to be meritorious.
It isn't politics. Equal time isn't given to competing ideas, that's not the way it works.
What you mean to say is that science isn't democratic. This is a result of its being a meritocracy and not a feel-good daycare where every idea gets a shot no matter how unmeritorious it may be. The following statement is a corollary:
the system would collapse without a hierarchy of opinion.
Quite right. The hierarchy of which you speak arises because not all ideas have equal merit; that is to say, not all ideas are equally scientific.
Hmm. Every time our knowledge of the universe expands, there is always a group of scientists who rush to say that the new evidence indicates that we are, in one way or another, the center of the universe. And when that conclusion is invalidated by still more new evidence, they go hunting for another reason to reinstate their conclusion. The "Rare Earth" faction is just the latest iteration of the same deep-seated emotional bias that gave us geocentrism.
We have exactly one stellar system that we have studied in detail and exactly one example of a living ecosystem, and all our knowledge of other stellar systems comes from techniques that exclusively detect stellar systems with a massive planet in a tight orbit around its star. It seems to me that our sample size is too small to reach any conclusions at all, and until we have better tools for observing other stellar systems in high detail, discussions about what constitutes a "normal" stellar system barely rise above the level of pure speculation.
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Doesn't seem to work out for me. Their logic is that star systems have a timeline related to gas giants, so star systems like ours are rare? I guess the problem here is the totally subjective word "rare" But I don't see how star systems nearly the same age as ours (far gas giants) can't be just as common as star systems that are older (near gas giants) So rare? probably, but same way you could say "people who live with their parents are rare, because when people get older they generally move out of their parents house" (and we're talking all people, not just adults)
Not all life is cyber. Extra Income
But space, the planets and galaxy are too numerous to imagine. Basically infinite.
Rare x Infinite = Infinite
They might be thousands of lights years apart, but there are still billions of them.
You and colmore are both right. Colmore beautifuly summarized how science actually operates. Your observations reflect understandings gleaned from the philosophy of science, in particular Karl Popper's falsifiability criteria. Popper developed this idea to show how one can delineate science from pseudo-science. It is a valuable philosophical insight and is useful as a criteria of demarcation between science and unscientific ideas. But, it is not a good foundation for understanding the actual methodologies used by science. Actual science proceeds based on some assumptions such as the uniformity of natural causes that cannot be proven, but which underlay belief in the validity of probabilistic induction and the idea that science illuminates "truth" in some sense and gives us greater knowledge of reality.
My understanding is that current methods of planetary detection favor finding large planets. From what I have read, planets are mostly detected using the wobble caused by the planets orbiting a star, and that the larger the planet and the closer to the star the more likely it is to detect a planet. I am not sure that a solar system like ours would be detectable using the methods currently in place. So this skews the sample. This study sounds premature to me.
As a working scientist: no he (colmore) didn't. Although his intentions were good.
In science you make some assumptions when creating your theory, but if you find evidence that indicates those assumptions are likely false then it's time to make a new theory. That INCLUDES such assumptions as the universe being consistent.
An excellent example of just that idea is quantum mechanics. The universe, it seems, isn't consistent in quite the way that classical physics thought it was: a cause doesn't always produce the same effect. When we discovered this, we designed quantum mechanics to take this aspect into account.
Both you and colmore use the word "prove." Science is not about proving things, and of course you cannot prove assumptions, or anything else, for that matter. In science there is no proof, because there is always the possibility that you will find a counterexample.
which is then savagely generalized to come up with the unwarranted conclusion that systems like ours are rare. They've got 250 systems observed, wrote a model to match that observation, then decided that the computer model is now the new thinking behind planet formation. It's only a computer model, and we have billions of more datapoints to collect. It ain't time to generalize yet.
Yes, for life to form as seen on Earth conditions must be close to what they are on Earth, but I'm certain that there are other paths for life to evolve along, some of them no doubt leading to sentience, that are beyond our current comprehension. The universe is a big place, there's no reason to be small minded...