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Was Earth a Migratory Planet?
astroengine writes "Why our planet isn't a "snowball Earth" — a dilemma called the 'faint young sun paradox' — has foxed solar and planetary scientists for decades. Since the Earth's formation, a planet covered in ice should have stifled any kind of greenhouse effect, preventing our atmosphere from warming up and maintaining water in a liquid state. Now, David Minton of Purdue University has come up with a novel solution that, by his own admission, straddles science fact and fiction. Perhaps Earth evolved closer to the Sun and through some gravitational effect, it was pushed to a higher orbit as the Sun grew hotter. But watch out, if this is true, planetary chaos awaits."
If this is the case, and the "chaos" that awaits is us migrating into a higher orbit, then whoopee, there goes us having to worry about the greenhouse effect... Oh wait... this isn't just another excuse not to curb our burning of fossil fuels is it?
Moved to http://soylentnews.org/. You are invited to join us too!
Earth is migratory
In fact, Earth received a Blue-green card as early as 3.5 billion years ago after passing a solar naturalization test.
"And then a miracle occurs" makes a good punchline but lousy science.
If Slashdot were chemistry it would look like this:Cadaverine
It is the consensus of 99% of climatologists that the earth isn't a snowball and therefore it is a fact that the earth has slowly moved into a higher orbit at exactly the same rate that the sun has warmed so as to maintain a climate on earth appropriate for life. The more we fill the atmosphere with greenhouse gases and thus heat the earth, the further the earth will move away from the sun so as to maintain an optimum climate. These "inconvenient truths" prove that there is an intelligent designer of the universe.
Q.E.D.
Planet migration theories have been floating around since the 1970s. Nothing new, but I guess Discovery's standards are continuing to fall.
Kind of like this...
If you could reason with religious people, there would be no religious people
Up until it found it was having humans. Then it had to settle down.
A substance that, when introduced into or absorbed by a living organism, causes death or injury, esp. one that kills by rapid action.
*breaths in*
That was just a bunch of CO2 I sucked in right there.
Even your argument that "everything is a poison in large quantities" is stupid, because it's not the CO2 harming you if you go in the garage and turn on the car - it's the fact you are not getting oxygen. The CO2 itself did not hurt you.
Plants also disagree with you. When you've made a plant frown how much lower can you go?
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Well, unless he's trying to be punny. Migratory planets were proposed by Immanuel Velikovsky in, among other things, his 1950 book "Worlds in Collision". His ideas were picked up by James P Hogan for his "Giants" series and other books. (James P Hogan was notable for adapting crazy theories into interesting books in his early years, but then digressing later in life to the point where he never met a conspiracy theory he didn't like.)
This Space Intentionally Left Blank
It was pulled into a larger orbit by swallows. Swallows.
it was brought here by a European Swallow?
make imaginary.friends COUNT=100 VISIBLE=false
Ah, so here's the deal. I'm the person that this article is talking about (David Minton, professor at Purdue University). I've been reading Slashdot for a fair number of years now, though it took me a long time to sign up and comment for the first time (I've always been a lurker at heart). Because I have a soft spot for all you basement dwellers (I kid!), I'm going to give you a bit of behind the scenes regarding this article, which kind of took me by surprise, actually. This is a bit long, so TL;DR: Science sometimes happens during panicked last minute coding sessions in hotel rooms prior to delivering invited talks that were procrastinated about.
So about five years ago my graduate school advisor and I wrote what was my very first peer-reviewed paper, which was on the subject of the Faint Young Sun Paradox. The paradox goes something like this: The early Sun was fainter than it is today, so all things being equal the Earth should have spend the first half of its life frozen over. Geologists tell us it wasn't, so something wasn't equal. What was it? We investigated the idea that the Sun may have been slightly more massive (something like 2-7% more massive), and that it had to lose most of that excess mass over a few billion years, which is at odds with measurements of mass loss of Sun-like stars. So we published it, and I went on to do other things in grad school, mostly involving trying to figure out the early impact bombardment history of the solar system, which we think may have been influenced by an early period of migration of the gas giant planets.
Fast forward to a few months ago, and a fellow at the Space Telescope Science Institute (the place they run the Hubble from) contacted me to ask if I'd like to give a talk about my old mass-losing Sun paper at a workshop that was planned to bring together astrophysicists, geologists, climate scientists, and planetary dynamicists to talk about the Faint Young Sun problem. They wanted me to also talk about planet migration and how that might fit in to the problem. Sure, why not? Revisiting the problem would be fun! The thing is, I've just started a new faculty job, and part of my job is helping get a new planetary science group built up at Purdue, so I've been extremely busy. And, well, I procrastinated. Big time. There was always some pressing thing to do that took time away from getting ready for the workshop. So the next thing I know, it's a few days before the meeting and I still haven't really thought about the faint Sun in about five years. So I dust off my old files, start futzing around with a talk, and the next thing I know I'm on a plane to Baltimore.
Late the night before the workshop is about to start, I'm racking my brain trying to come up with something new to say. You see, I've been thinking about early solar system history, and planet formation. Migration is a big deal in those early days. It's easy to get planets to move around in young solar systems. But the Faint Young Sun problem is a problem for the Earth's mid-life, not it's adolescence. Then I remembered a paper I really liked that came out a couple of years ago by Jaques Laskar and Mickaël Gastineau. They showed that our own solar system could potentially destabilize after a few billion years of seeming-stability due to Mercury's proximity to a chaotic region. It's described briefly here: http://en.wikipedia.org/wiki/Stability_of_the_Solar_System#Laskar_.26_Gastineau
What if something like that had happened *already?* So I futzed around with an N-body gravitational dynamics code remotely from my hotel room, in my pajamas, playing around with plausible initial solar systems where Earth stared just a tad closer to the Sun, but close enough to solve the problem of being frozen over, and Venus started out as two separate planets and then went unstable after many billions of years, scattering Earth to its present location in the process. And, when I checke
Your post is neither less stupid than the GP nor informative.
Re: Sucking
It was also just a bunch of CO2 you blew out.
Re: Your ridiculous claims.
*Everything* that kills you works by disrupting something your body needs to do to live. You might as well say paralyzing venoms don't kill you, it's the lack of oxygen because your lungs aren't working. Does that mean venom isn't poison? No.
Re: Car scenario
The CO2 in your scenario doesn't kill you. The CO does that. CO2 CAN kill you, though. Maybe you've heard of hypercapnia. (Note the URL, too.)
Re: Plants
Just because something is not poison to ONE organism does not mean it is not a poison.
It was pulled into a larger orbit by swallows. Swallows.
African or European?
If you could reason with religious people, there would be no religious people
I'm not an astrophysicist, but I'll respond to the part about the amount of energy 'to push the Earth away'. It's all about conservation of momentum. If one planet moves closer to the sun, something else has to move out. Big Jupiter might move in a little by pulling a small planet like earth or Mars out a lot. No energy is 'lost'. One might even argue that energy is not even used, just passed around. To give a relatively simple example of how the motions of the planets are more complicated than the simple models we learn as kids in school, consider that the fact that the moon is slowing down the rotation of the earth though tidal action means that that angular momentum has to go to the moon, so it's orbit is gradually getting further away from the earth. And yeah, some energy is 'lost' in this case because of tidal friction. It would only become 'stable' when the earth was rotating at such a speed as to be in lock step with the orbit of the moon so that the moon was always directly above the same place on the earth like communications satellites are now.
In theory, theory and practice are the same; in practice they're different. (Yogi Berra & A. Einstein)
One of the amazing consequences of the Kolmogorov-Arnold-Moser theorem (KAM) is that the Earth orbit is stable, despite the influence of Jupiter. Stable in this context means that the orbit perturbations caused by Jupiter and the other planets don't cause the Earth orbit to move too close or too far from the Sun, causing dramatic changes of temperature.
Chaos theory when gravitation is involved is not so chaotic as one could expect: the KAM theorem tells us that multi-body systems governed by gravitation law have intrinsic stability regions.
He's a fraud.
I'll give you 74 virgins
74 virgins for all eternity? If they stay virgins, you're probably in Hell. Otherwise... even if you just bonk one per quadrillion years, you run out before you've put a scratch in eternity.
Lurid offer, but meaningless if you pause to think about it. Once per quadrillion years is like offering you a chance to be a Slashdotter for all eternity.
My religion, OTOH, offers you one skilled courtesan. Or gigolo - my Heaven offers something for everyone.
Or dominatrix...
Sheesh, evil *and* a jerk. -- Jade
They could grip it by the crust.