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Comment Re:The definition is fine (Score 1) 95

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.

Comment Re:The definition is fine (Score 2) 95

Saying pluto is a dwarf planet seems pretty good to me as it gives it a special place among planet like objects already.

If they had simply stopped there, that wouldn't have been a problem. The problem is that they didn't. They declared that dwarf planets aren't planets at all - which is nonsense. Mars has far more in common with Pluto than, say, Jupiter. If anything should have been separated out, it's the gas and ice giants from the rocky/icy planets.

Hydrostatic equilibrium is a very meaningful dividing line to split groupings on. If a body is in hydrostatic equilibrium, it's experienced dramatic geologic change in its history - differentiation, tectonics, internal heating, generally fluids (particularly liquid water), and on and on. It's the sort of place you go if you want to learn about planetary evolution or search for life. If a body is not in hydrostatic equilibrium, it's made of primordial materials, preserved largely intact. It's the sort of place you go to learn about the formation of our solar system and its building blocks.

It's rare that nature gives you such clear dividing lines, but when it comes to planets, it has. It's not perfect - you can (and do) have bodies that straddle the border and are only partially or slightly differentiated. But in general, nature has drawn an obvious line in the sand, and we should respect that.

if the object is really big and clear

Is Earth's orbit clear? No, we have a huge massive object co-orbiting with us. Is Neptune's orbit clear? No, it has Pluto in it. They try their hardest to pretend that the IAU actually chose a "gravitationally dominant" standard, but that's not what they actually put in the definition. The standard in the definition is "cleared the neighborhood".

And it's based on a false premise - that each planet cleared its own neighborhood. Which is just pseudoscience. All of our models show that Jupiter, and to a lesser extent Saturn, cleared most of the solar system, including the vast majority of the clearing around Mars, and a good fraction around Earth (lesser around Venus). Mars did not clear its own neighborhood. Nor is it gravitationally dominant in its neighborhood; the vast majority of asteroids are in orbital resonance with Jupiter and not Mars.

And I've heard some people try to sneak around this by saying "Okay, maybe it isn't gravitationally dominant / cleared its neighbood now, but it has enough of a Stern-Levison parameter that it would have been had Jupiter not existed". First off, that's changing the definition yet again (to "would have cleared its neighborhood if no other planets were there"). But beyond that, it's abuse of the Stern-Levison parameter. The Stern-Levison parameter is built around a body's ability to clear asteroids - bodies with the current size and orbital distribution of our asteroid belt. Not protoplanets. In the early solar system it was the ability to clear protoplanets that caused neighborhoods to be cleared. Jupiter got rid of some really massive things that were forming in and near the inner solar system. There's a reason why our planetary system has such an unusual size distribution: the inner planets start getting bigger, the stop getting bigger, then get small, then debris, then something huge. That "something huge" stripped the building blocks out of the inner solar system, preventing it from becoming dominated by super-Earths. Saturn appears to have been our savior - its (delayed) formation appears to have stopped Jupiter's inward migration.

And even just going with the Stern-Levison parameter - Neptune has a Pluto-sized body in its "neighborhood". Now, Pluto may be small compared to Neptune, but compared to Mars it wouldn't be - yet Mars has a much lower Stern-Levison parameter than Neptune. Again: the only reason Mars doesn't experience stuff like this is because Jupiter cleared its neighborhood for it.

Comment Re:Maybe (Score 1) 95

Clearly given that people like Stern have regularly given interviews decrying the decision, and going so far as to call it "bullshit" (can you say that at NASA?), it's clearly not the storm in a teacup that you want to present it as.

What the proponents did was take a term widely used by planetary geologists and have it mean something completely different - akin to dentists suddenly declaring to doctors that the heart is no longer an organ and to stop referring to it as one. And contrary to your presentation of why they did it ("to make it easier to write journal articles") without fail every last supporter I've seen interviewed about their vote has given some variant of the following reason for why they voted the way they did: "I don't want my daughter having to memorize the names of hundreds of planets." Which is so blatantly unscientific it's embarrassing that such a thing would influence their decision at all on a scientific matter.

The IAU vote was narrow, at a conference only attended at all by a fraction of its membership, on the last day when a lot of the people opposed to the definition they passed had already left because it had looked up to that point like there was either not going to be a vote at all , or one on a hydrostatic equilibrium definition - all options that they were fine with. Only 10% of the people who attended were still around.

I have a lot of issues with the last vote, and that's just the start. Here's my full list:

1. Nomenclature: An "adjective-noun" should always be a subset of "noun". A "dwarf planet" should be no less seen as a type of planet than a "dwarf star" is seen as a type of star by the IAU.

2. Erroneous foundation: Current research agrees that most planets did not clear their own neighborhoods, and even that their neighborhoods may not always have been where they are. Jupiter, and Saturn to a lesser extent, have cleared most neighborhoods. Mars has 1/300th the Stern-Levison parameter as Neptune, and Neptune has multiple bodies a couple percent of Mars's mass (possibly even larger, we've only detected an estimated 1% of large KBOs) in its "neighborhood". Mars's neighborhood would in no way would be clear if Jupiter did not exist - even Earth's might not be. Should we demote the terrestrial planets as well?

Note that the Stern-Levison parameter does not go against this, as it's built around the ability of a planet to scatter a mass distribution similar to our current asteroid belt, not large protoplanets.

3. Comparative inconsistency: Earth is far more like Ceres and Pluto than it is like Jupiter, yet these very dissimilar groups - gas giants and terrestrial planets - are lumped together as "planets" while dwarfs are excluded.

4. Poor choice of dividing line: While defining objects inherently requires drawing lines between groups, the chosen line has been poorly selected. Achieving a rough hydrostatic equilibrium is a very meaningful dividing line - it means differentiation, mineralization processes, alteration of primordial materials, and so forth. It's also often associated with internal heat and, increasingly as we're realizing, a common association with subsurface fluids. In short, a body in a category of "not having achieved hydrostatic equilibrium" describes a body which one would study to learn about the origins of our solar system, while a body in a category of "having achieved hydrostatic equilibrium" describes a body one would study, for example, to learn more about tectonics, geochemistry, (potentially) biology, etc. By contrast, a dividing line of "clearing its neighborhood" - which doesn't even meet standard #2 - says little about the body itself.

5. Mutability: Under the IA definition, what an object is declared as can be altered without any of the properties of the object changing simply by its "neighborhood" changing in any of countless ways.

6. Situational inconsistency: (Related) An exact copy of Earth (what the vast majority of people would consider the prototype for what a planet should be), identical down to all of the life on its surface, would not be considered a planet if orbiting in the habitable zone of a significantly larger star (harder to clear zone), or a young star (insufficient time to clear), a star without a Jupiter equivalent (no assistance in clearing), or so forth.

7. Ambiguous definition: There is still no consensus on what defines having "cleared the neighborhood" - in particular, what the "neighborhood" is.

8. Lack of terminology: Exoplanets - indeed, including any potential Earthlike planets - are arbitrarily declared to not be planets. Meaning that exoplanets are not actually planets according to the IAU. Ironically, the IAU has an exoplanets working group called "Executive Committee Working Group Public Naming of Planets and Planetary Satellites"... tasked with naming things that it doesn't consider planets.

9. Inability to describe exoplanets even if not ruled out: There is no way that even if exoplanets hadn't been arbitrarily ruled out that one could ascertain whether a body has met a "cleared the neighborhood" via observations from Earth. A definition based on hydrostatic equilibrium would be far easier to ascertain.

10. Failure to address binary objects. Self-explanatory.

11. Unscientific motivation: The primary reason cited by everyone interviewed thusfar for choosing an exclusive standard over an inclusive standard is along the lines of, "It would be too hard for schoolchildren to memorize the names of all of them". This is such a blatantly unscientific standard that it doesn't even bear going into, and leads to absurd consequences when applied to other fields, such as the AMA declaring that there's only 8 bones in the human body and all others are "dwarf bones" that aren't real bones, or the USGS declaring that there's only 8 rivers in the world and all others are "dwarf rivers" that aren't real rivers, all for the purpose of making things easier for students to memorize.

12. Resistance to accept the diversity of reality: In every scientific field, the universe continually presents those making discoveries with a wide range of diversity. This is almost universally accepted in an inclusive manner, subdividing groups into subgroups, and subdividing those further. We will continue to find new types of planetary bodies in a wide range of diversity - large terrestrial planets, dwarf-scale planets, gas giants, ice giants, hot jupiters, super-earths, water worlds, supercomets, extremely large bodies orbiting as moons, planets without parent stars, and so forth. Rather than trying to hide diversity, science is supposed to embrace it.

13. Discouragement of exploration among the public: The term "planet" has a deep and meaningful place in the public mind, as a body worthy of exploration, perhaps even eventually colonization. "Small solar system body" does not. Public support for scientific exploration to these diverse and fascinating worlds should not be discouraged by poorly chosen names. Quite to the contrary, it would be worthwhile if fascinating worlds the diameter of Mercury, like Ganymede and Titan, were given the same level of attention with a label such as "planetary moons" (note again: an "adjective-noun" is a subcategory of "noun").

14. Distrust of the scientific population among the public: Images of discontent scientists sniping at each other and divisive voting on controversial "truths" have a profoundly negative consequence on the public's view of the scientific community. Anyone who spends any time looking at any of the internet commentary on the dwarf planet decision will find them full of comments along the lines of "Scientists can't even agree about whether Pluto is a planet, why should we trust them about global warming?" I wish this were hyperbole, but I've seen it far too often to ignore it.

15. Poor voting statistical representation: While 4% of the IAU would make up a statistically significant sample if chosen at random, the people involved were not "chosen at random". The people present were "those who could take a trip to Prague and didn't have to leave before the closing ceremony", which leads to numerous potential biases. As Owen Gingerich noted, "There were 2,700 astronomers in Prague during that 10-day period. But only 10% of them voted this afternoon. Those who disagreed and were determined to block the other resolution showed up in larger numbers than those who felt 'oh well, this is just one of those things the IAU is working on'." In this day in age where electronic balloting is simple to implement, that the IAU would be willing to make charged decisions on a 60% vote of a non-random 4% of the membership is highly inappropriate.

16. Wrong people making the decision: Only a small percentage of the IAU are planetary scientists, who are the actual people who should be the ones making decisions about what makes up a planet. Letting people who study stars decide what counts as a planet is akin to letting dermatologists decide how to treat a heart condition - hey, a doctor's a doctor, right? Just like when meteorologists or chemists make claims that global warming isn't real - a scientist is a scientist, right?

17. Making the decision before gathering the data: For most of the history of humankind's knowledge of Ceres and Pluto, we have not had any missions underway to explore them. They were just poorly resolved points of light. But at the time of the IAU vote, at long last, we had launched New Horizons to Pluto and were preparing Dawn for launch to Ceres. Yet it was at this narrow interval, between actually launching craft to gather data about the bodies, but not having them arrive, that the IAU decided to make their declaration. Making scientific declarations about objects that you know little about when vast amounts of data are coming in the pipeline - data that could influence members making the decision - is profoundly unscientific.

18. Not following through on its own declarations: The IAU decision declared that it would continue to name new dwarf planets as new data comes in. Yet there's not been a new declaration since 2006. We have far better data than we had to make declarations of dwarf planets in 2006, and there's a long list of them awaiting declaration - where's the IAU? For example, Quaoar's diameter is known to a mere ±5 km and is significantly larger than Ceres. Even the lower bound of 2007 OR10 is larger than Quaoar. Why aren't they and countless others on the list? It increasingly looks like the IAU just wanted to make its declaration purely for demotion purposes rather than for its stated purpose of categorization.

19. Disagreement with the IAU is so intense that those who disagree are simply ignoring it - a process that began in the literature almost immediately (example: http://arxiv.org/abs/0712.2198), let alone in conversations with the public (example: any press conference with the New Horizons team). This not only renders the definition meaningless but serves to undercut the IAU's authority in other issues (such as naming).

20. Beyond the major points I could go into a bunch of nitpicks about the poor wording the IAU put forth in general. Such as how Jupiter doesn't actually meet their definition because the sun and Jupiter orbit a point (the sun-Jupiter barycentre) that spends most of its time outside the sun. It's often mentioned how Neptune doesn't meet their definition because of their use of the term "cleared the neighborhood" (implying removing all other large objects) rather than being gravitationally dominant / forcing other bodies into resonance. But because of that, even the Earth doesn't meet that definition because Earth's moon - which orbits the sun as much as the Earth does, despite also orbiting the Earth - is not cleared. Indeed, the IAU definition accepts that a body can both "orbit the sun" and be "a satellite" (see rule #2), yet they don't mention the satellite exclusion in rule #1, thus making Earth fail section (c) of #1. Using a "gravitationally dominant" definition rather than a "cleared the neighborhood" definition would have fixed this problem, but they didn't. Even if one chooses to ignore this, Earth's moon (despite being larger than most dwarf planets) gets classed not as a dwarf planet or even as a moon, but a "small solar system body", because - as they observe in #2 that objects can be both satellites and orbit the sun as well - it fails the conditions in #1 and #2 but meets the orbital condition in #3, thus is a "small solar system body". If you choose not to ignore that they choose the wording "cleared the neighborhood" rather than "gravitationally dominant" in #1, then Earth too is a "small solar system body". These are, of course, nitpicks, and are more ambiguous than the previous points; they're presented simply to show how hastily the current definition was come up with and how poorly thought out it is.

Comment Counter-example (Score 1) 159

Owning a Cat Does Not Lead To Mental Illness, Study Finds

The people who did this study never met the lady who lives on the end of my block. She's completely cuckoo and owns like a hundred cats. Sometimes they wander over to my yard just to get away from the old bat. I'll bet if I walk outside right now, there'll be one sitting on the cushion on one of my deck chairs. He likes to hang out with me when I sit outside at night and watch the basketball game. Wait, does that mean I own a cat? Holy shit. I better get myself checked out.

Submission + - Microsoft Research's DeepCoder AI may put programmers out of a job

jmcbain writes: Are you a software programmer who voted in a recent Slashdot poll that a robot/AI would never take your job? Unfortunately, you're wrong. Microsoft, in collaboration with the University of Cambridge, is developing such an AI. This software "can turn your descriptions into working code in seconds. Called DeepCoder, the software can take requirements by the developer, search through a massive database of code snippets and deliver working code in seconds, a significant advance in the state of the art in program synthesis." Another article describes program synthesis as "creating new programs by piecing together lines of code taken from existing software — just like a programmer might. Given a list of inputs and outputs for each code fragment, DeepCoder learned which pieces of code were needed to achieve the desired result overall." The original research paper can be read online.

Submission + - Obama's Feds Tried to Hack Indiana's Election System While Pence Was Governor

EmmaStarc writes: Department of Homeland Security (DHS) officials tried to hack Indiana’s state electoral system with at least 14,800 “scans” or hits between Nov. 1, 2016, to Dec. 16, 2016, The Daily Caller News Foundation Investigative Group has learned.

The attacks are the second confirmed IT scanning assault by DHS officials against states that resisted then-President Barack Obama’s attempt to increase federal involvement in state and local election systems by designating them as “critical infrastructure” for national security. .Source

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