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Comment Re:Maybe (Score 1) 186

Indeed, on both counts. And in particular I like the word "rogue planet". Again you have an adjective imparting additional information about another object ("Rogue X"), "rogue" can be readily quantified ("Not in a stable orbit around any particular star or cluster of stars"), and it's a very evocative term. And rogue planets are absolutely expected according to our current models. They'll be incredibly difficult to find, but they're out there.

We're also coming to the realization that there's a lot of objects, potentially including large ones, that are only tenuously bound to our solar system. And it's likely that we readily exchange this mass with other nearby stars over cosmologic timescales; parts of our solar system (primarily distant ones) likely formed by other stars, and things that condensed during the formation of our star system are likely now orbiting other stars.

Comment Re:C strikes again (Score 1) 48

and ASM

Would the ASM have been bug-free?

Would any other language, with ANY amount of safe-guards been physically incapable of producing an off-by-one in it's output code?


This is quite literally "Ragel took a definition, and then compiled it to bad machine code". Whether that was via an intermediary language or not, that's possible with ANY compiler for ANY language. If Java had a bug in it that resulted in incorrect machine code being generated for the "safe" Java code it was asked to execute, the same would have happened.

Bad, buggy compiler. The fact that it used an intermediate language which you disagree with is neither here nor there (and Ragel could output asm direct, so it wasn't "C-specific"). No different to a JVM-compiler bug.

Comment Re:Not Science, Medicine (Score 1) 263

Uh, no. This is where a good scientist keeps digging into it in order to expand our level of knowledge.

In which case your original premise that "causation is frequently so complex that it can not be deciphered with our current level of knowledge" is not correct. You cannot have it both ways: either the causation is understandable - with hard work and insight - or it is not. If it is understandable then this is what a scientist will go after because understanding is their goal. For a medical researcher establishing causation is enough which is very susceptible to random statistical flukes.

Comment Re:scare mongering getting old (Score 1) 77

We froze both of our credit files after the identity theft. It's useful when stores try to pressure you to "save 5% now if you just sign up for our card." Nope. No can do. My credit's frozen due to identity theft. That shuts them up real quick. On the down side, though, we gave up on refinancing our mortgage a couple of years ago even though we could have saved money. It was too much of a headache to thaw our credit, get the mortgage quotes, and try to get everything signed before the freeze took effect again.

Comment Re:Fake science/sloppy science (Score 1) 263

You have that wrong, I think. Sure, the Scientific Method is not about building a consensus, however, the Advancement of Science (as in expanding our understanding of the universe), has to be about consensus. Without consensus on what is true (or likely to be true), Science would perennially be stuck at what a single scientist could accomplish in one lifetime. At some point, you have to accept that other scientists have already researched and discovered things. At that point, the scientific consensus will help you find areas for your own research that haven't already been exhaustively studied.

Of course, there is nothing stopping someone for challenging the consensus on any scientific topic, but if you do want to challenge the consensus, then you better have a good alternate theory and the evidence to back it up.

Comment Re:Not Science, Medicine (Score 1) 263

No, they focus on correlation because causation is frequently so complex that it can not be deciphered with our current level of knowledge.

Exactly but if they were a scientist then this is when they would stop and go and look at a different problem that they can decipher with our current level of knowledge. That is part of being a good scientist: you have to tackle things which you can ultimately understand because it is that understanding which is the goal of science. In medicine the correlation is enough: if substance X or activity Y cures ailment Z that's good medicine, why and how is of secondary importance.

Comment Re: s/drug trials/climate change/g (Score 3, Informative) 263

Record high temps, record low temps. record rain, record drought.

That's actually what you'd expect with a chaotic system built of multiple random variables. It would be unnatural for weather to always be the same.

Actually it's not. It's a simple fact that in a stable system, as time goes on, there are fewer and fewer "record" events because each new record needs to be more extreme than all previously recorded events. Over time, record-breaking events decline significantly. So, an increase in record events is, by itself, evidence that the system is undergoing change.

Comment Re:Maybe (Score 1) 186

The short of it, Jupiter moves things around; it's very good at scattering other bodies, even large ones. First it dragged outer populations into the inner solar system, then scattered inner solar system material out, and then on its retreat pulled outer solar system material back in. It's actually a very big deal that it did that, as it brought ice into the inner solar system.

Comment Re:Maybe (Score 1) 186

1. "Adjective nouns" need to have similarity to "noun" but aren't necessarily a subset. Gummy bears aren't a subset of bears either.

Gummy bears are not a scientific term. Besides, the IAU itself already uses the word dwarf in this manner. Dwarf stars, dwarf galaxies... but carved out an inexplicable exception for dwarf planets.

I'd like to see a citation on this. I highly doubt that you can simulate the formation of a solar system where multiple Mars analogues can coexist in the same orbit

False equivalency. There's a difference between "two Mars sized planets existing in the same orbit" and "Mars' orbit having been cleared". And more to the point, the biggest problem with the concept of Mars clearing its orbit is that its orbit was already largely cleared when it formed. According to our best models, Jupiter reached all the way in to around where Mars' orbit is today, and had cleared almost everything to around 1 AU. Earth and Venus accreted from planetesimals between each other. Mars accreted from planetary embryos ejected to the space in-between Earth and Jupiter. Without Jupiter's migration, simulations produce an Earth-sized Mars and several planetary embryos in the asteroid belt on eccentric / high inclination orbits, something akin to the situation between Neptune and Pluto - except with the embryos nearly Mars-sized.

3. In a geological sense yes. But the current definition of planets is based on orbital mechanics, after which Earth is a lot closer to Jupiter than to Ceres/Pluto.

Huh? By what aspect of orbital mechanics? By semimajor axis and velocity, Earth is much closer to Ceres than Jupiter. Are you talking inclination and eccentricity? Then we should boot Mars in favour of low inclination / eccentricity asteroids.

4. Hydro-static equilibrium as a dividing line is way worse. There are roughly 100 TNOs where we don't really know whether they are elliptical.

Hydrostatic equilibrium can be very easily estimated based on mass, which can be approximately deduced within a range of feasible albedos and densities, and very accurately deduced if the body has a moon. By contrast, it's almost impossible to estimate neighborhood clearing to any distance beyond Neptune, or at all in the case of extrasolar planets. Which, to reiterate, the IAU definition says aren't planets, even though they have an extrasolar planet working group.

We'd have to visit each and every one of them with a probe just to put them in the proper category.

This is utter nonsense.

Meanwhile, it's completely clear which bodies qualify for the "clearing its orbit" rule.

No, it's not. We have virtually no clue what lies in the outer reach of our solar system. As we speak there's a search for a new planet that could be as big as an ice giant. It's a huge open question as to whether it would have cleared its neighborhood, and it will be very difficult to ascertain.

All currently qualifying planets have roughly 99% or more of the mass in their orbit in themselves. Ceres has 30%.

You seem to have some weird concept going on that "semimajor axis = orbit". Ceres has nothing of significance in its orbit. The asteroids are not all in the same orbit. They're certainly more likely to cross each others orbits, but that's not the same thing.

And again, since you apparently missed it: the reason that the inner solar system is largely cleared except for the asteroid belt (and the reason that the latter exists) is Jupiter. Mars did not clear its own neighborhood.

5. The definition should be mutable. Why should a planet that gets ejected keep counting as a planet?

You seriously have to ask why something that hasn't changed but is in a different location shouldn't suddenly be declared to be something entirely different? If you take a rabbit to Canada does it suddenly become a dwarf rabbit?

6. I highly doubt life could form in a non-cleared orbit.

Once again, you're stuck on this misconception that the only orbital parameter that exists is the semimajor axis. And also apparently a notion that stable orbital resonances don't exist.

Orbits can come in a wide range of forms. If you want to see how crazy they get, check out Epimetheus and Janus ;)

As for a life bearing celestial in orbit around another (gas giant) planet: I don't think anybody feels bad about calling that one a moon? As in "Yavin 4".

The funny point with your example being, that whenever you illustrate a large round (hydrostatic equilibrium) moon in sci-fi - Star Wars, Star Trek, Avatar, whatever - people invariably keep calling it a planet and having to correct themselves. We inherently recognize "large, round object with relevant gravity = planet", and have to shoehorn our minds into not using that term.

7. "Within each other's periapsis and apoapsis" seems like a reasonable enough definition that neither Ceres nor Pluto qualify for.

Once again, you ignore most orbital elements (seriously, stop right now and go read the Wikipedia article on orbital elements). We don't live in a 2D solar system. And your notion is oversimplified even for 2D.

All of this, let alone other aspects such as mass ratios, resonance, metastability, etc. And it gets even more complicated when you view the solar system not as a 2-body problem but a multi-body problem. Then things like horseshoe orbits, Lagrangian points, etc come into play.

8. Yes that's silly but that'll probably be changed easily enough and has no effect on Pluto.

1) It's over a decade later. Where's the fix?
2) It's just a symptom of how horribly hasty and ill-thought-out their action was.

9. How are you planning to ascertain hydro-static equilibrium for an exoplanet if we can't even do it for Varuna.

What are you talking about? Varuna is the size of Ceres. The fact that it hasn't been declared a dwarf planet by the IAU is again a symptom of the IAU's dysfunction on this issue. See #18. By contrast, we'd have no snowball's chance in hell of identifying all potential orbit crossers for it.

The fact that you bring up Varuna makes me think that you feel it shouldn't be a planet because it's an oblate spheroid. If so, that just reveals yet another problem with your understanding: you need to go look up the definition of hydrostatic equilibrium. Hint: if Varuna wasn't an oblate spheroid, then it wouldn't be in hydrostatic equilibrium.

Comment Not Science, Medicine (Score 5, Interesting) 263

This is medical research, not science. Medicine uses science because often the best way to cure something is to understand it but, very importantly, it has a very different motivation to science. Finding a "magic" pill which cures disease X without side effects but whose mechanism is completely unknown is great medicine but appalling science. Science is all about understanding how things work, medicine is all about treating human ailments.

This leads to a different approach using the tools of science. Medical researchers tend to focus far more on correlation over causation because that is what is most important to this. Unfortunately this approach leaves them open to random statistical effects which require a very good understanding of statistics to avoid and even then it can still be very easy to fool yourself e.g. the Monty Hall effect.

So lets call this problem what it is: a problem with medical research.

Comment Re:TL;DR something you claim is cogent...? (Score 5, Informative) 186

The IAU spend months in total hashing out this issue and three days talking in meetings before the vote

That's just the issue: that's not what happened. The IAU discussion was a disaster. Here's the timeline:

2005: The IAU appoints a committee to investigate the issue and generate a proposal. The committee investigated the issue for a year.

The IAU meeting is scheduled from 14-25 August 2006.

16 August: The committee recommends a definition based on hydrostatic equilibrium. No "cleared the neighborhood" nonsense. They publish their draft proposal.

18 August: The IAU division of planetary sciences (aka, the people who actually deal with planets) endorses the proposal.

Also 18 August: A subgroup of the IAU formed which opposed the proposal. An astronomer in the group (aka, someone who studies stars, not planets) - Julio Ángel Fernández - made up his own "cleared the neighborhood" definition. While most of the membership starts to trickle away over the next week, they remain determined to change the definition.

22 August: The original, hydrostatic equilibrium draft continued to be the basis for discussion. There were some tweaks made (some name changes and adjusting the double-planet definition), but it remained largely the same.

Late on 22 August: Fernández's group manages to get to just over half of the attendance at the (open) drafting meeting, leading to a very "heated" debate between the two sides.

22 to 24 August: The drafting group begins to meet and negotiate in secret. The last that the general attendance of the conference knew, they'll either end up with a vote on a purely hydrostatic definition, or (more likely) no vote at all due to the chaos. Attendence continues to dwindle, particularly among those who are okay with either a hydrostatic definition or none at all.

24 August: The current "cleared the neighborhood" definition is suddenly proposed and voted on on the same day. Only 10% of the conference attendance (4-5% of the IAU membership) is still present, mainly those who had been hanging on trying to get their definition through. They pass the new definition.

It's not generally laypeople who are upset about how it went down, it's IAU members. Many have complained bitterly about it to the press. The IAU's own committee of experts was ignored, in favour of a definition written in secret meetings and voted on by a small, very much nonrandom fraction of people, the vast majority of whom do not study planets.

If there's one thing I hate, it's people who pretend that anyone who opposes the IAU definition does so because they're ignorant morons overcome by some emotional attachment to Pluto, when in reality it's been planetary scientists themselves who have been the definition's harshest critics, because it's an internally self-inconsistent, linguistically flawed, false-premise-based definition that leads to all sorts of absurd results and contradicts terminology that was already in widespread use in the scientific literature.

Comment Re:The definition is fine (Score 1) 186

Exactly. I think Stern's always been on the right side of this. The original paper that the Stern-Levison parameter comes from has a great system laid out, where you have a bunch of adjectives that you can apply to different bodies based on their varying physical (composition, size) and orbital parameters, and you can use any combination of them as needed. Which seems to me to be so obviously the right solution.

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