APOD: Kepler 78b: Earth Sized Planet... (2013 Nov 05)

[geckzilla]

the notion that we humans are the natural endpoint of evolution. Its almost as bad as religiosity in its premise.

Yes, Rob, we're all sitting here trying to tell you that there are other humans all over the universe. I apologize for the sarcasm but I feel like you're preaching to the choir here without realizing it. I get it. We don't know what's out there and we can't make assumptions. All we can do is do the best that we can do to search for evidence. I haven't read anything in this thread by anyone stating otherwise other than posts by you inferring that we are overzealous alien lovers.

[robgendler]

Well here I am making friends again on asterisk . Seriously its been a good discussion. We are all very opinionated and all I'm doing is expressing my opinion. Chris.....I agree that evolution is not a random process but that is not the same as saying there are inevitable outcomes which are predictable. What may I ask are the predictable outcomes? Evolution is driven by selective pressures whether they be geologic, climatic, etc. and these are essentially random and capricious. Selective pressures influence evolutionary outcomes but these are hardly predictable. Some degree of genetic variation is due to random mutations. I have a feeling you are trying to say that intelligence is an inevitable outcome but maybe I'm reading into it.

[Nitpicker]

Faith has different meanings, some of which I would find offensive if applied to me. The bottom line is that defining simple belief as "faith" devalues and confuses both words. I am a proponent of precision in the use of language, and suggesting that "faith" is required by scientists seems to me both inaccurate and imprecise. So when such an assertion is made, I will argue against it.

I believe in things for which I have objective reason to believe; I have faith in absolutely nothing.

I suggest you write a stiff letter to the publishers of whichever dictionary you fancy. Good luck trying to expurgate the imprecision. I think Big Brother had some success with Doublespeak. Edit: oops, I think I mean Newspeak.

Me, I love both the precision and the richness offered by the English language. If there is ambiguity in the meaning of a word, you can often seek clarification. But if that is impractical, do you always assume the meaning which offends you most? I don't. And sometimes, when appropriate, I like to ponder the other possibilities too. I do so love semantics.

[Nitpicker]

Geometrically speaking Humans are the geometric
mean between the largest and smallest things.

This permits them to be the most complex
though not necessarily the most logical.

I suppose if I can forgive Pythagoras his folly in numerology, I can forgive you too, neufer.

[Nitpicker]

Doublespeak. Edit: oops, I think I mean Newspeak.

That's the most satisfying mistake I've made in ages. Confusing doublethink and Newspeak has such a delicious irony. Such thoughtcrime!

[Beyond]

Do i detect the beginnings of a Nitpicker Dictionary

[Nitpicker]

Do i detect the beginnings of a Nitpicker Dictionary

Undeserving of such praise. I haven't invented or redefined any of the words I've used in this topic. Most of the credit for that goes to the OED and George Orwell.

[Nitpicker]

And while we're on the topic of semantics ...

I understand that some humans consider (or considered) some observations to provide evidence for the existence of, for instance, god(s). This implies to me that all evidence has a quality, good or bad. As such, I think what separates science from many other pursuits of knowledge, meaning and understanding, is the judgement of the evidence, not the evidence itself. Good judges can be hard to find. Not to mention that you first have to define "good".

(I hope I am not judged too harshly for this somewhat metaphysical side note.)

[Chris Peterson]

I understand that some humans consider (or considered) some observations to provide evidence for the existence of, for instance, god(s). This implies to me that all evidence has a quality, good or bad. As such, I think what separates science from many other pursuits of knowledge, meaning and understanding, is the judgement of the evidence, not the evidence itself. Good judges can be hard to find. Not to mention that you first have to define "good".

In science, judgment of evidence is a product of consensus. Consensus is critically important to science, but is one of its most misunderstood (sometimes deliberately) aspects.

[BDanielMayfield]

The word and concept of faith has been kicked about quite a bit in this thread. I thank geckzilla and nuefer for posting dictionary definitions of faith, and Nitpicker for his points on the broader meanings of this word. On the one hand faith can mean a set of religious beliefs. Many are without this type of faith, and even proudly so. They have the right to this point of view of course.

But as the definitions show faith can be had in all manner of things. I like this definition, which can be applied to any set of expectations, religious or otherwise:

Faith is the assured expectation of what is hoped for; the evident demonstration of realities that are not seen.

I haven’t seen the sun come up tomorrow yet, and yet I have strong faith that it will, an assured expectation based on the convincing, demonstrated evidence that the Earth’s rotation and the Sun’s radiation are dependable.

Chris, you equate faith with credulity, which is why you could state that you “have faith in absolutely nothing”. But I also “believe in things for which I have an objective reason to believe.” Not all faith is baseless. Strong faith is rooted in convincing evidence, not blind credulity.

[Chris Peterson]

Chris, you equate faith with credulity, which is why you could state that you “have faith in absolutely nothing”. But I also “believe in things for which I have an objective reason to believe.” Not all faith is baseless. Strong faith is rooted in convincing evidence, not blind credulity.

I didn't say that faith was baseless. I said it is belief in the absence of evidence. If you prefer, I'll say in the absence of objective evidence. In any case, the suggestion that I have "faith" in science is inaccurate, except for the most weak meaning of simple belief. In reality, the only time I ever hear that is when the claimant is comparing "faith" in science to "faith" in religion (whether they honestly admit that or not). Of course, there is no comparison. Other than sharing the same five letters in the same order, they are different words.

[Nitpicker]

Chris, I believe this is where the discussion of faith started in this topic:

Your confidence is more a matter of faith than of knowledge. That's fine, you may well be right, but we don't know yet. And faith is a powerful force. It's is helpful, however, to be clear about when we're acting on faith.

Your speculation on my level of confidence is unfounded. I have enough knowledge to have faith in the search for more knowledge, but trying to quantify which of the two is greater sounds a little "unscientific" to me. My statement "it will bear some similarity to the current understanding" was hardly a bold one. But some level of faith (in science) will always be required, unless you are searching for something you already know (that just requires forgetfulness).

I am not 100% sure which particular kind of faith Anthony was suggesting, but I do think my reply clarified the kind of faith I was suggesting.

[Ann]

Chris wrote:
But given how quickly life formed on Earth, and how unremarkable our planet appears to be

I realize that this is getting old now, but that statement of yours keeps bothering me, Chris. How can we be so sure that our planet is unremarkable?

It goes without saying that Earth-mass or Earth-size planets must be a dime a dozen in the universe. There can be no reason whatsoever to believe that there is anything strange or unusual about the size or the mass of the Earth.

It could be, however, that planets with the Earth's mass and size are a bit more unusual. The Earth is a comparably dense planet, denser than Mercury, Venus and Mars.

It is obvious that the Earth is not made of any strange materials. It could be, however, that the Earth contains a larger than usual fraction of radioactive components which keep part of the Earth's interior liquid and make it possible for the Earth to keep its strong magnetic field. The magnetic field is crucial for protecting the Earth's atmosphere.

It could be that the Earth's tectonics has been unusually efficient in recycling the surface material of the Earth.

It could be that the surface of the Earth is unusual, in that the Earth has got both continents and oceans. A planet rich in surface water might have no dry land at all. On such a planet it might be impossible for a technological civilization to appear, since it would probably be impossible to make fire.

It could be that the interplay between oceans, continents, ice and plate tectonics on the Earth constantly injects energy and recycles materials in a way that is uncommon for planetary bodies.

Other details, like the stabilizing influence of our large Moon, might also help make the Earth "extra habitable". Personally I can't help wondering if the creation of the Moon, if indeed it is a product of a collision between the young proto-Earth and a Mars-sized body, also gave the Earth an extra helping of core material and radioactive materials that have kept the Earth's magnetic field strong.

It could be that, on top of these favorable circumstances, the size and shape of the Earth's orbit around the Sun have also been extremely favorable in keeping water liquid on the surface of the Earth.

It could be, too, that the Sun has been a comparatively "well-behaved" star. Kepler data suggest that other Sun-like stars are typically more variable than the Sun.

I keep wondering if the Earth is not the product of a series of lucky circumstances that have turned our planet into a quite rare gem of Goldilocks habitability.

Ann

[mjimih]

I suspect that the preponderance of "any" life out there is quite limited in commonness by the periodic table. Life on Earth is 98% hydrocarbon based right? Does the periodic table lend itself to other types of life? Or are hydrocarbons basically it? If so, then life would need to follow a similar path wherever it pops up. Ergo life as we know it could only arise on planets "extremely" similar to Earth. How might the table of elements restrict or enhance the probability of other types of life? And are there planets that can support these unknown life-"forms"

[neufer]

Geometrically speaking Humans are the geometric
mean between the largest and smallest things.
This permits them to be the most complex
though not necessarily the most logical.

I suppose if I can forgive Pythagoras his folly in numerology, I can forgive you too, neufer.

What about Kepler

[mjimih]

I keep wondering if the Earth is not the product of a series of lucky circumstances that have turned our planet into a quite rare gem of Goldilocks habitability.

Ann

I think u r exactly spot on! A lonely jewel, one-of-a-kind. Maybe serendipity has something to do with it too. Speaking of luck, we'll be lucky if we can clean up after the party, before our parents come home

[robgendler]

Chris wrote:
But given how quickly life formed on Earth, and how unremarkable our planet appears to be

I realize that this is getting old now, but that statement of yours keeps bothering me, Chris. How can we be so sure that our planet is unremarkable?

It goes without saying that Earth-mass or Earth-size planets must be a dime a dozen in the universe. There can be no reason whatsoever to believe that there is anything strange or unusual about the size or the mass of the Earth.

It could be, however, that planets with the Earth's mass and size are a bit more unusual. The Earth is a comparably dense planet, denser than Mercury, Venus and Mars.

It is obvious that the Earth is not made of any strange materials. It could be, however, that the Earth contains a larger than usual fraction of radioactive components which keep part of the Earth's interior liquid and make it possible for the Earth to keep its strong magnetic field. The magnetic field is crucial for protecting the Earth's atmosphere.

It could be that the Earth's tectonics has been unusually efficient in recycling the surface material of the Earth.

It could be that the surface of the Earth is unusual, in that the Earth has got both continents and oceans. A planet rich in surface water might have no dry land at all. On such a planet it might be impossible for a technological civilization to appear, since it would probably be impossible to make fire.

It could be that the interplay between oceans, continents, ice and plate tectonics on the Earth constantly injects energy and recycles materials in a way that is uncommon for planetary bodies.

Other details, like the stabilizing influence of our large Moon, might also help make the Earth "extra habitable". Personally I can't help wondering if the creation of the Moon, if indeed it is a product of a collision between the young proto-Earth and a Mars-sized body, also gave the Earth an extra helping of core material and radioactive materials that have kept the Earth's magnetic field strong.

It could be that, on top of these favorable circumstances, the size and shape of the Earth's orbit around the Sun have also been extremely favorable in keeping water liquid on the surface of the Earth.

It could be, too, that the Sun has been a comparatively "well-behaved" star. Kepler data suggest that other Sun-like stars are typically more variable than the Sun.

I keep wondering if the Earth is not the product of a series of lucky circumstances that have turned our planet into a quite rare gem of Goldilocks habitability.

Ann

Thank you Ann! You said it much better than I could. I wish Chris would qualify his comments as being his "opinion" rather than in a presumptive way as if they were proven facts. Saying the earth is an unremarkable planet is a very presumptive statement not backed by any real science what so ever.

[neufer]

Click to play embedded YouTube video.

Speaking of which...I just saw the SciFi movie _Oblivion_ on Netflix
and I figured out that Tom Cruise calls his dashboard BOBble head:
"BOB" in honor of BOB Seger & his "Old Time Rock & Roll."

I keep wondering if the Earth is not the product of a series of lucky circumstances that have turned our planet into a quite rare gem of Goldilocks habitability.

I think u r exactly spot on! A lonely jewel, one-of-a-kind. Maybe serendipity has something to do with it too. Speaking of luck, we'll be lucky if we can clean up after the party, before our parents come home

[img3="BOBble head: "BOB""]http://1.bp.blogspot.com/-6mIOWOJ752o/U ... on+bob.bmp[/img3]

[owlice]

Rob,

I didn't see Chris stating that he was speaking of complex life; where did he do so?

It seems to me you are very close to "true biologists = anyone working in biology (especially astrobiology) I disagree with." I certainly hope I'm wrong about that.

You have to admit astrobiology is a strange field.......the study of something in which we have absolutely no proof of its existence. I don't mean any disrespect....but to enter a field in which there is absolutely no proof of the existence of the subject matter would require an overzealous (and unrealistic) belief that it exists. Can you name another field of science which is similar? Also I'd love to see a few high ranking specialists in the field who have their "primary" training in the biological sciences. I doubt you can provide any. That says a lot since "biology" is part of the name they adopted. Again not a scientific field which I can regard in any serious manner.

But there IS proof of its existence -- life on Earth. I don't find astrobiology a strange field at all. I think it quite natural and reasonable to look for what is here out there.

I think I'm about to find a good deal of irony in your posts about this, however.... how much "primary" training (I take it by "primary" training, you mean academic coursework) do you have in astronomy?

[Nitpicker]

Geometrically speaking Humans are the geometric
mean between the largest and smallest things.
This permits them to be the most complex
though not necessarily the most logical.

I suppose if I can forgive Pythagoras his folly in numerology, I can forgive you too, neufer.

What about Kepler

I'm prepared to forgive Kepler too. If I lived with the threat of serious religious persecution, I think I'd be quite a different person. Similarly, I respect Copernicus (a priest) and his ultimate decision to present his results less as a representation of reality (heaven forbid), but more as an easier method for predicting planetary motion! Though that may have been the work of a sub-editor. Authorship issues are tricky things.

I might be less forgiving of Titius and Bode though. Not sure.

[neufer]

I suppose if I can forgive Pythagoras his folly in numerology, I can forgive you too, neufer.

What about Kepler

I'm prepared to forgive Kepler too. If I lived with the threat of serious religious persecution, I think I'd be quite a different person. Similarly, I respect Copernicus (a priest) and his ultimate decision to present his results less as a representation of reality (heaven forbid), but more as an easier method for predicting planetary motion! Though that may have been the work of a sub-editor. Authorship issues are tricky things.

I might be less forgiving of Titius and Bode though. Not sure.

[b][color=#0000FF][size=150]Johann Elert Bode: [i]Wink Wink[/i][/size] Bovaird and Lineweaver applied a generalized Titius-Bode relation to 68 exoplanet systems which contain four or more planets. They showed that 96% of these exoplanet systems adhere to a generalized Titius-Bode relation to a similar or greater extent than the Solar System does. The locations of potentially undetected exoplanets are predicted in each system.[/color][/b]

---

<<The Titius–Bode law (sometimes termed just Bode's law) is a hypothesis that correctly predicted the orbits of Ceres and Uranus, but failed as a predictor of Neptune's orbit. It is named for Johann Daniel Titius and Johann Elert Bode. The law relates the semi-major axis a of each planet outward from the Sun in astronomical units (AU):

for m=-∞,0,1,2...

For the outer planets, each planet is predicted to be roughly twice as far from the Sun as the previous object.

There is no solid theoretical explanation of the Titius–Bode law, but if there is one it is possibly a combination of orbital resonance and shortage of degrees of freedom. Orbital resonance from major orbiting bodies creates regions around the Sun that are free of long-term stable orbits. Results from simulations of planetary formation support the idea that a randomly chosen stable planetary system will likely satisfy a Titius–Bode law. [However,] astrophysicist Alan Boss states that it is just a coincidence, and the planetary science journal Icarus no longer accepts papers attempting to provide improved versions of the law.

Dubrulle and Graner have shown that power-law distance rules can be a consequence of collapsing-cloud models of planetary systems possessing two symmetries: rotational invariance (the cloud and its contents are axially symmetric) and scale invariance (the cloud and its contents look the same on all scales), the latter being a feature of many phenomena considered to play a role in planetary formation, such as turbulence.

The four big satellites of Jupiter and the biggest inner satellite, Amalthea, cling to a regular, but non-Bode, spacing with the four innermost locked into orbital periods that are each twice that of the next inner satellite. The big moons of Uranus have a regular, but non-Bode, spacing. However, according to Martin Harwit, "a slight new phrasing of this law permits us to include not only planetary orbits around the Sun, but also the orbits of moons around their parent planets." The new phrasing is known as Dermott's law.>>

<<Dermott's law is an empirical formula for the orbital period of major satellites orbiting planets in the Solar System. It was identified by the celestial mechanics researcher Stanley Dermott in the 1960s and takes the form:

for n = 1, 2, 3, 4...

Where T(n) is the orbital period of the nth satellite, T(0) is of the order of days and C is a constant of the satellite system in question.
Specific values are:

• Jovian system: T(0) = 0.444 d, C = 2.03
  Saturnian system: T(0) = 0.462 d, C = 1.59
  Uranian system: T(0) = 0.488 d, C = 2.24

Such power-laws may be a consequence of collapsing-cloud models of planetary and satellite systems possessing various symmetries. They may also reflect the effect of resonance-driven commensurabilities in the various systems.>>

[Nitpicker]

I may have been unfair to Titius and Bode. Not really numerological, just not analytical.

As for Copernicus and his sub-editor, I have mis-remembered this story slightly. From:
http://en.wikipedia.org/wiki/Osiander

"In 1543 [shortly before the death of Copernicus], Osiander [a Lutheran theologian and friend of Copernicus] oversaw the publication of the book De revolutionibus orbium coelestium (On the revolution of the celestial spheres) by Copernicus. He added a preface suggesting that the model described in the book was not necessarily true, or even probable, but was useful for computational purposes. This was certainly not the opinion of Copernicus, who was probably unaware of the addition. As a result, many readers, unaware that Osiander was the author of the preface, believed that Copernicus himself had not believed that his hypothesis was actually true. Osiander also did not sign the preface added to Copernicus' book, therefore many readers at the time assumed that this is what Copernicus had actually thought himself."

[BMAONE23]

I understand that some humans consider (or considered) some observations to provide evidence for the existence of, for instance, god(s). This implies to me that all evidence has a quality, good or bad. As such, I think what separates science from many other pursuits of knowledge, meaning and understanding, is the judgement of the evidence, not the evidence itself. Good judges can be hard to find. Not to mention that you first have to define "good".

In science, judgment of evidence is a product of consensus. Consensus is critically important to science, but is one of its most misunderstood (sometimes deliberately) aspects.

Wouldn't it be better stated that "Judgement of evidence (through science) is a product of confirmation"? It seems to me that support or rejection of theory is better handled through confirmation of findings rather than consensus of arguement. Or am I misinterpreting your usage?

[Chris Peterson]

Chris wrote:
But given how quickly life formed on Earth, and how unremarkable our planet appears to be

I realize that this is getting old now, but that statement of yours keeps bothering me, Chris. How can we be so sure that our planet is unremarkable?

I say that because I can't identify anything remarkable. That doesn't mean "common", of course.

We orbit a star of a common type. We observe similar stars with rocky planets, and we have well developed dynamical theories about why that should be. We have three planets in just our own system that had conditions apparently suitable for life to develop, and one where we know for sure it did. All had plate tectonics, all had magnetic fields. But there's really no reason to think either are necessary in order for life to develop. All the evidence-solid observational evidence, argues that our system and planet are unremarkable, that there is nothing unique about them at all.

Again, I'm making no claim about anything beyond simple life. Not animals, and certainly not technological civilizations.

[Chris Peterson]

Wouldn't it be better stated that "Judgement of evidence (through science) is a product of confirmation"? It seems to me that support or rejection of theory is better handled through confirmation of findings rather than consensus of arguement. Or am I misinterpreting your usage?

Of course, confirmation is critical. It's part of what creates consensus. But it's a different thing than what I'm talking about. The degree of consensus among experts about any theory correlates closely with the likely truth of that theory.