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

[Slushcritter]

"Models of planet formation predict that no planet can form in such a close orbit..."

Maybe the models need tweaking. Maybe it's nto a planet.

[Chris Peterson]

"Models of planet formation predict that no planet can form in such a close orbit..."

Maybe the models need tweaking. Maybe it's nto a planet.

The formation models are still being refined. I think it's safe enough to say these are planets. My guess would be that we're simply seeing planets that formed in one orbit and moved to another, something we know can happen.

[FloridaMike]

....Models....are powerful tools....

True, just not to be confused with the final answer, lest we forget.

[Chris Peterson]

....Models....are powerful tools....

True, just not to be confused with the final answer, lest we forget.

I don't even know what a "final answer" is when we are talking about the nature of nature.

[Slushcritters]

"I don't even know what a "final answer" is when we are talking about the nature of nature."

Excellent answer, Chris, and one which should leave us all open to every idea, not matter how farfetched it seems.

[Chris Peterson]

"I don't even know what a "final answer" is when we are talking about the nature of nature."

Excellent answer, Chris, and one which should leave us all open to every idea, not matter how farfetched it seems.

I don't think my comment implies yours.

Ideas should be weighed by their quality, by how well they match theory and observation, by how well theories are tested. Yes, in a technical sense, skepticism requires being open to all ideas that haven't been proven wrong (and ideas most certainly can be proven wrong!) But "being open" should never be taken as "being equally open". Some ideas are much better than others, and it is a mistake not to recognize that. In actual practice, ideas range from highly speculative to well enough established that they can be functionally treated as facts.

[robgendler]

That is very well said Chris.....I couldn't agree with you more. I'm not against the research regarding the subject of today's APOD but the implications of the findings might belong to that state of having too much "open mindness" you are talking about. This new field of "Astrobiology" seems to consist of exclusively physical scientists. I haven't noticed any evolutionary biologists speaking at their conferences or collaborating with their projects. The reason is that folks who do biology for a living have a clear understanding that the idea of extraterrestrial civilizations or just complex life is at best a romatic one spawned by wishful thinking and with little knowledge of the complexity of evolutionary history on our own planet. The Drake equation is the best example of this type of silliness which passes as science.....an attempt by a non-biological scientist to explain in a simple equation what generations of brilliant evolutionary biologists have never been able to explain....the rise of complex life on this planet.

[Ron-Astro Pharmacist]

Not being a highly math-skilled person, non-the-less it would be interesting to try and comprehend the complexity and logic required to solve a solution such as determining orbits of faraway planets by the various methods. As in the December edition of Astronomy where it’s attempted to describe some of the more famous equations, I am curious if it would be possible to describe various calculations for those of us who will probably never know. Although done with computers those in the know still need to understand the equations, and their limitations, to write such programs.

Point is, I think it would be interesting if a particular program (and its math) could be rated in difficulty and complexity so we amateurs would know how hard it really was to do the math. Maybe they all are.

Talk about being a nerd.

[CygnusOB2]

Planets and planetary systems appear to be extremely diverse. Why does this surprise anyone ? I recently stated this fact in a post about the newly discovered KIC 11442793 system. Shall I post these words every time an announcement about a newly discovered planet is made. Tell your friends, your family, your neighbours. Tell everyone you meet : we are learning that planets and planetary systems are extremely diverse !

[Chris Peterson]

Not being a highly math-skilled person, non-the-less it would be interesting to try and comprehend the complexity and logic required to solve a solution such as determining orbits of faraway planets by the various methods. As in the December edition of Astronomy where it’s attempted to describe some of the more famous equations, I am curious if it would be possible to describe various calculations for those of us who will probably never know. Although done with computers those in the know still need to understand the equations, and their limitations, to write such programs.

Point is, I think it would be interesting if a particular program (and its math) could be rated in difficulty and complexity so we amateurs would know how hard it really was to do the math. Maybe they all are.

The methods used for determining orbits of bodies around much more massive centers are generally simple, based only on Newtonian and Keplerian formulas (you can read about orbits on Wikipedia). Understanding systems with more bodies is not really possible using any simple theory or any deterministic equation of motion. Such systems are modeled using various types of numerical simulation. Basically, the physical environment is simulated, with each particle's state being computed at a given time using (typically) Newtonian methods. These simulations are generally robust and testable, and physics-based (as opposed to empirical). This approach describes many areas of modern science, as we increasingly seek to understand complex systems. Such systems cannot be analyzed by any closed mathematical analysis. From a scientific standpoint, "theories" and "models" are basically the same thing, but "theories" usually describe low level or simple processes, and "models" describe complex processes that must be analyzed using more than one simple theory at the same time.

[Ron-Astro Pharmacist]

I suspect you are right. To rate the difficulty of a calculation one would need to also rate the ability to understand. A general description such as lines of code in a program or program run time would probably really not tell much about the true complexity of a calculation or richness of the information it spewed as cosmologic simulations may demonstrate. (Very cool but the math behind it maybe not as complex)

Additionally I’ll rate your answer a 10 and my ability to comprehend those calculations less than or equal to “one hands” worth.

As always thanks for your thoughts and comments. Ron

[Anthony Barreiro]

It would have been helpful to have distance from earth in this description. How far away is it?

I agree, but it looks like we don't know. I checked the Extrasolar Planet Database online and the distance to Kepler 78 is not given.

Who says that our planetary origin and planetary evolution models are correct. They're just models based on our observations to date. Twenty years from now they won't resemble what the are today.

Science is not a book of answers; it's a process of learning. Of course, 20 years from now we'll know more about how our planet was created and how it evolved, but we are extremely unlikely to find out something so astounding that it blows away our current theories in the way you suggest. Scientific understanding increases incrementally, not through explosive revelation.

Rob

On the 50th anniversary of the publication of Thomas Kuhn's Structure of Scientific Revolutions, I beg to differ. Normal scientific understanding increases incrementally, until internal inconsistencies lead some bright mind to propose a pardigm shift, a new way of looking at existing data. This is usually experienced as an explosive revelation. The transition from the Ptolemaic to Copernican models is the prime example of such a scientific revolution, and revolutions have continued in every discipline ever since. My layperson's hunch is that our current models of dark matter and dark energy may be ripe for a new and explosive revelation. But what do I know?

By the way, I can't find dkidroske's original comment to which Rob responded. I assume it was expunged for violating Starship Asterisk's version of scientific orthodoxy, leaving the thread looking like an airbrushed photo of the Soviet Politburo.

[owlice]

Thanks, Anthony, for characterizing the work of the volunteers who clean up the messes from people who violate the Asterisk rules as "looking like an airbrushed photo of the Soviet Politburo." That's very kind of you.

[geckzilla]

I want to note that removing just that post was an experiment by me. It was clearly written with anti-science undertones but the following conversation was still interesting and informative. Often I am left with the decision to either cut everything out or to leave it all. This time I tried a hybrid approach, which I thought might work because then instead of having the comment on its own, it is read with rebuttals by others. As one of the first comments, as it was, there was a good chance it would have been only read by itself with subsequent replies ignored. The problem is, of course, that the more regular and attentive readers notice this. Anyway, It's very hard for me to tell what the right thing to do sometimes. If you ever have any problems or concerns with moderation, I would appreciate it if you PM'ed me about it. It would be insightful to me to have an opinion from any of the regular users here.

[Chris Peterson]

On the 50th anniversary of the publication of Thomas Kuhn's Structure of Scientific Revolutions, I beg to differ. Normal scientific understanding increases incrementally, until internal inconsistencies lead some bright mind to propose a pardigm shift, a new way of looking at existing data.

As somebody very interested in both the history of science and the philosophy of science, I'd say that Kuhn's ideas are increasingly irrelevant to how science works. The model was good when we didn't know much. That's when new knowledge genuinely led to paradigm shifts. But shifts in major areas haven't happened for a long time, and small scale shifts are rather trivial.

The thing is, we sort of know everything now... at least, to a first approximation. We don't seem to have any major knowledge areas where we know virtually nothing, or where our fundamentals are likely to be wrong. At this point, the advancement of knowledge really is incremental; we don't see wholesale shifts in theory, or scientific revolutions. I can't think of any non-trivial area of science where I think there is a likelihood of a Kuhn-style paradigm shift occurring.

(And no, this isn't some sort of "everything has been invented" assertion. There's a lot we still don't know, but most of it is detail around existing theories that are probably broadly accurate representations of nature.)

[Nitpicker]

On the 50th anniversary of the publication of Thomas Kuhn's Structure of Scientific Revolutions, I beg to differ. Normal scientific understanding increases incrementally, until internal inconsistencies lead some bright mind to propose a pardigm shift, a new way of looking at existing data. This is usually experienced as an explosive revelation. The transition from the Ptolemaic to Copernican models is the prime example of such a scientific revolution, and revolutions have continued in every discipline ever since. My layperson's hunch is that our current models of dark matter and dark energy may be ripe for a new and explosive revelation. But what do I know?

Hi Anthony,

To counter your counter argument, I feel compelled to refer to another famous tome: On the Shoulders Of Giants, edited by Stephen Hawking.

See the following link for details of the book:
http://www.amazon.com/On-The-Shoulders- ... 076241698X

Hawking has compiled a collection to demonstrate how one discovery, however limited, led to another. As such, I would characterise each new discovery as a correction, enhancement or refinement, rather than a paradigmatic shift.

The transition from Ptolemaic to Copernican models, was a biggie, to be sure, but it was arguably more revolutionary for the human psyche and social structure, than it was to astronomy. It still amazes me that epicyclic models do as well as they do in predicting the motion of the planets.

I certainly do hope that science gains a better insight into dark matter and dark energy in my lifetime. But whenever it happens, I am confident it will bear some similarity to the current understanding.

[Anthony Barreiro]

I certainly do hope that science gains a better insight into dark matter and dark energy in my lifetime. But whenever it happens, I am confident it will bear some similarity to the current understanding.

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.

[Nitpicker]

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).

[Ann]

When it comes to dark matter and dark energy, we are observing something. We can repeat the same observations over and over again and get the same results. Admittedly we don't know if our interpretations of our observations are correct.

But when it comes to life elsewhere in the universe we are observing nothing, unless the discovery of many exoplanets inside the habitable zones of stars should count as an observation of life. But to me that seems like a gross misunderstanding of what a reasonable interpretation of an observation is. And if we conclude that a certain fraction of planets inside the habitable zones of stars equals technological civilizations, then we are really taking things on faith.

Of course we don't really have the technology that we need to actually discover life many light-years away from the Earth, but the planets in our own solar system are not beyond us. If there has ever been life on Mars, and certainly if Martian life forms are still there, it would not be beyond our capabilities to detect them. If we find clear signs of past or present life on Mars that is clearly non-terrestrial in origin, then that would boost our confidence enormously that life is common in the universe. But as long as Mars hasn't yielded any signs of life, how can we be so sure that the rest of the universe is teeming with life, let alone intelligent life?

Ann

[rstevenson]

By the way, I can't find dkidroske's original comment to which Rob responded.

I talk to ghosts -- but only if I've scientifically determined that they are real ghosts, of course.

Rob

[FloridaMike]

I am loving this discussion, everyone is making good points. Keep it going!!!

[Nitpicker]

Neufer recently explained why he believes that there are at least 265,000 stars with planets hosting intelligent life forms in the universe. Unfortunately his post didn't make much sense to me. Since I am a complete amateur it is no wonder if I don't understand the reasoning of professional astronomers, and it is of course impossible for me to make any sort of guess at how many planets with indigenous intelligent life forms there might be. Neufer's estimate may be perfectly correct for all I know, but what I don't understand is how he can be so sure.

I'm not sure that the "de facto professional" neufer is so sure of his estimate. An estimate is sometimes not much more than an educated guess, in the absence of enough information to be properly analytical, or even probabilistic about the problem.

I'm also not sure why neufer took the square root of Sagan's number in his estimate. Sounds spurious to this "de facto intelligent" life form.

[neufer]

Neufer recently explained why he believes that there are at least 265,000 stars with planets hosting intelligent life forms in the universe. Unfortunately his post didn't make much sense to me. Since I am a complete amateur it is no wonder if I don't understand the reasoning of professional astronomers, and it is of course impossible for me to make any sort of guess at how many planets with indigenous intelligent life forms there might be. Neufer's estimate may be perfectly correct for all I know, but what I don't understand is how he can be so sure.

I'm not sure that the "de facto professional" neufer is so sure of his estimate. An estimate is sometimes not much more than an educated guess, in the absence of enough information to be properly analytical, or even probabilistic about the problem.

I'm also not sure why neufer took the square root of Sagan's number in his estimate. Sounds spurious to this "de facto intelligent" life form.

The square root of Sagan's number is geometrically half way between:

• 1) The maximum number of star systems that might generate intelligent life (i.e., Sagan's number) &
  2) The minimum number of star systems that have generated intelligent life (i.e., one: us).

13,700 years is probably an underestimated of the lifespan of intelligent life
especially considering that we haven't blown ourselves up yet.

[Nitpicker]

The square root of Sagan's number is geometrically half way between:

1) The maximum number of star systems that might generate intelligent life (i.e., Sagan's number) &
2) The minimum number of star systems that have generated intelligent life (i.e., one: us).

Yep, Ann, that's about as spurious as picking the arithmetic halfway point. In other words, astronomically spurious. (And without mentioning the assumptions regarding coinciding life spans.) But it is possibly as good as any other estimate.

How did we get talking about intelligent life on other planets anyway? This APOD concerns an uninhabitable planet which should not exist (and soon may not).

[Chris Peterson]

I certainly do hope that science gains a better insight into dark matter and dark energy in my lifetime. But whenever it happens, I am confident it will bear some similarity to the current understanding.

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.

No faith is required. We already have a good understanding of how dark matter fits into cosmology, and some very plausible ideas of where it is in the Standard Model. We also have a nice model of dark energy as a component of our best cosmological model, even in the absence of any real understanding of its fundamental nature. Indeed, we can understand many things quite well while knowing nothing about their true natures (if that's even a meaningful question). Our understanding is largely satisfied if we have a predictive theory that is consistent with observation. Right now, the evidence supports the supposition that as we learn more about both dark matter and dark energy, our basic cosmological model isn't going to change radically.