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Comment Re:"Denali" = anagram for "Denial" (Score 1) 362

I don't have a very clean way - I usually do egrep "^......$" /usr/share/dict/words (with the number of dots matching the length of the word) and then pipe it into a series of other greps - for example for two "r"s I'd do egrep -i "r.*r" while for one d I'd just use grep -i "d". There's probably a better way.

Comment Re:For me, it will always remain the mountain... (Score 4, Interesting) 362

I can't remember who it was... it might have been Halldór Laxnes... who said that a piece of nature isn't really a piece of nature unless it doesn't have a name. That is, the first thing people do once they start interacting with an object or place is to give it a name, and so once something is named it starts to become about the history of people rather than the history of the land itself. And that if you want to establish a real connection with nature, you don't go sit on top of that well-known named peak that people climb... you go to that little nameless stream or that remote nameless cliff or whatnot - places which tell only their own story.

Comment Re:Tradeoffs (Score 1) 43

More to the point, the James Webb telescope is supposed to be launched in late 2018; this flyby isn't until 2019. With seven times the light collecting area as Hubble, it could be a nice addition to the arsenal for finding bodies along Pluto's projected route (especially now that we know better what that route is going to be :) ) Though it operates in mid-IR to low-frequency visible, while Hubble operates primarily in visible/UV... I'm not sure how that would affect the ability to find solid objects. I know that far-IR is very good for it, but James Webb doesn't go down that far.

Comment Re:"clearing the neighborhood" (Score 1) 43

It's even worse than that. Compare Neptune's Stern-Levison parameter to Mars's. Neptune has at least two bodies that are each around 2-3% the mass of Mars in its "neighborhood" (quite possibly even larger ones), yet it has 290 times greater ability to "clear its neighborhood" than Mars. The concept that planets like Mars cleared their own neighborhood of bodies this size is not only unsupported by the research, but blatantly silly on the face of it. The IAU is attributing Jupiter's work at clearing the inner solar system to the inner planets in order to force their definition. And this isn't exactly news - pretty much all orbital dynamics simulations for a long time have been showing this.

Comment Re:While we're on the topic... (Score 1) 43

Mars is more than capable of clearing its neighborhood on its own, as seen by measures like the Stern-Levison parameter and others that have been derived from dynamics and simulation scalings. It isn't even close to being marginal.

Jupiter's Stern-Levison parameter is 1,38 million times larger than Mars's. No, Mars would not have "cleared its neighborhood"; it's well recognized in the literature that the majority of "neighborhood clearing" in our solar system was done by Jupiter and Saturn. There's lots of niggling over the exact details (here's one scenario), but there's no reputable peer-reviewed source involving orbital dynamics simulations arguing that Mars did the majority of work to clear its neighborhood. Heck, Neptune has a Stern-Levison parameter 290 times higher than Mars and it still has at least two bodies with around 1/50th the mass of Mars each in its neighborhood (and possibly even larger ones). If a 290 times greater ability to clear its neighborhood couldn't do it, why do you think Mars stands a chance on its own?

The whole "cleared the neighborhood" concept for planets is built on a bare falsehood: that the majority of them are actually responsible for clearing their own neighborhoods. The science says exactly the opposite: that the gas giants cleared the majority of bodies from our solar system.

Because some people care more about the dynamics of the planets and their orbits than what is on/in the planets. Even in geology on Earth, there are classifications for what makes up a mineral, and classifications for structures and locations they are found in.

Are you seriously trying to claim that, say, stilbite will be classified as a different mineral based on whether it occurs in Iceland or the United States? Minerals are what they are. The individual structures minerals are found in may have names (for example, the "Bakken Shale"), but those are just names. You know, like "Kuiper Belt".

Some geologists don't care where it came from as long as the make up is similar, others very much care if samples come from near the same location, even if they are very different minerals.

What on Earth are you talking about? If you're trying to say "Some scientists want to study the variety of objects in the Kuiper Belt and compare them to each other", then you already have a word for that: KBO.

You can go on and on about how dissimilar you think Jupiter and Earth are, but that doesn't change that there are metrics where they are much more similar than other rocky planets are to Earth.

You can't be serious.

Comment Re:A-10 for the Win (Score 2) 414

You realize that in that evaluation, the F-35 being tested was AF-2, a flight science model, right? It had:

  * No situational awareness software
  * No advanced weapons targeting software
  * No stealth coating

It was not designed to be a combat evaluation of the full system, rather just an attempt to stress the system with visual combat maneuvers.

That said, the F-35 is not designed to be a visual dogfighter. It has dogfighting capabilities, but its main design principle is high situational awareness enabling kills from far away - seeing the enemy from long before it itself is seen.

Comment Re:While we're on the topic... (Score 1) 43

1. Is just a nomenclature problem. The key issue was whether Pluto belongs in the same category as Mercury through Neptune.

First off, the problem category was called "nomenclature". Secondly, you act like mercury has bloody anything at all in common with Jupiter and Saturn. It's far, far more like Pluto. It's not an "edge case" issue, it's a fundamental misgrouping issue.

2. If a planet changes its orbit, one of two things will happen:

It clears its new neighborhood
It gets cleared out by a new neighbor or falls into a resonance with it

As was mentioned, this is not correct. Mars-sized planets don't clear their own neighborhoods. Mars did not clear its neighborhood - Jupiter did. Your "two things" are simply not accurate. It's a false supposition that's the entire foundation of this definition.

More to the point, extrasolar planets show how ridiculous this definition is even more. There are extrasolar planets larger than Earth which orbit their star closer to each other at times than the Earth is to the moon. They don't "clear" each other at all. It's just a ridiculous, completely false premise.

3. and 4. In geological terms yes, but I think the IAU was correct in preferring to define planets through orbital characteristics over geological ones.

Why? Why should we define what something is based on where it is rather than what it is? The answer is basically given in the question itself. When you say, "X is a planet", you're making a statement about what it is. That's the meaning of the word is. If you want single words to talk about orbits, we already have terms for that - that's what "asteroid", "KBO", etc are.

And really, you completely avoided these points. Pluto and Earth are far more like each other than either are like Jupiter. So grouping Earth with Jupiter and not Pluto is a complete absurdity. Hydrostatic equilibrium is a meaningful distinction - it has all sorts of consequences for the body. The nobody-can-agree-upon "neighborhood" definition has little to no bearing on what you're going to find there.

5. The neighborhood of a planet cannot be simply changed without significant consequences. If through some freak incident a formerly solitary planet ends up suddenly having a neighbor of significantly higher mass, that planet will not remain a planet for very long. Its "mutability" is then not even restricted to definition games, it will quite be literally destroyed or thrown away into deep space.

These are anything but the only two options. They can change orbits, migrate inward, migrate outward, get locked into new resonances, etc. A planet can be moved into for example a more out-of-plane orbit by an intruder and still receive the same insolation, and thus be exactly the same on the surface, but no longer be a planet. It's an absurdity.

6. An Earth-copy that hasn't cleared its neighborhood yet won't be an Earth-copy due to frequent crust destroying meteorite impacts

That's not true. For one example among many, the Earth copy and the other bodies in its neighborhood could both be in orbital resonance with a larger body.

. Such a child solar system will probably not be described well by our current terminology but these systems are also very rare because that phase of life only lasts for a very short time.

Yet another unsupported statement.

7. There will clearly eventually be edge cases, but Pluto isn't. There is an object with 10000 times its mass within its perihel and apohel. Its orbital period is not independantly "chosen" but defined by Neptune

And if Earth were located where Pluto is now, its orbital period would also not either be indepdently "chosen" but defined by Neptune.

Should I even bother mentioning that one of the leading theories to explain Sedna's orbit is that there is a roughly Earth-sized body out there? WISE isn't capable of spotting such small objects.

8. - 10. Those are all things that we are just now starting to discover.

No, they're not. We've known about exoplanets and binaries long before the IAU definition.

They might eventually change up the definition of the word planet again

They refuse to revisit the issue.

such as when we do find the first binary pair of planets with similar mass in the same orbit.

We already have one, Pluto-Charon. They refuse to acknowledge it. And binaries don't just affect planets - there are even binary asteroids.

11+ are mostly political points where you can have an opinion either way.

Dismissing points as "political" is a nice way to not have to actually address their substance.

But scientifically the question is: Are Pluto, Ceres, Eris and the 100+ other yet to be discovered KBOs really similar enough to the big eight to be in the same category.

Given that they're far more similar to Earth than Earth is to Jupiter? YES. Unambigulously yes. If you want to take them out of the category, you also need to say that either the terrestrial planets aren't planets, or the gas giants and ice giants aren't planets. And the ice giants really shouldn't be grouped with the gas giants anyway. Or we can just stop all of this nonsense and accept the practical definition that hydrostatic equilibrium is a really meaningful bound, and then subdivide "planet" into planet categories from there - dwarf, terrestrial, gas giant, ice giant, and all of the strange new types we're discovering in other star systems.

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