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Comment Re:/. editors: why do you maintain this shit hole? (Score 2) 734

Donald Trump broke this place.

Not really, no. /. used to be mostly liberal/libertarian with a large slice of middle-of-the-road. Rightwing nutjobs, facists, and Nazis-in-all-but-name used to be downmodded into oblivion within minutes of posting.

Then Gamergate happened.

Within a few months, /. culture was almost completely inverted - and the rightwing nutjobs, facists, and Nazis-in-all-but-name gained ascendance. Things have only gotten worse since then.

Comment Re:And you should learn to read before replying. (Score 1) 135

I guess you missed where he clearly stated that it was the post office (specifically, Deutsche Post) which was responsible for the manner in which the packages were taped together, not the sendor *or* the recipient.

I guess you missed the part where the sender did a crappy job of packaging - and the Deutsche Post had to do the best they could with the pile of shit he dropped on their counter.

Comment Re: Fake News (Score 1) 270

1. That was just an old theory, and not a widely accepted one.

2. Given what we've just seen, it demonstrably isn't.

That doesn't mean that there aren't compounds formed at great pressure that can remain stable at moderate pressures and represent very dense energy sources - there surely are. Metastability is a very real thing. But apparently not in the case of metallic hydrogen at ~STP.

Assuming that this actually even was metallic hydrogen; even that is somewhat in dispute.

Comment Re:Maybe (Score 1) 204

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: 2nd (Score 1) 126

In what way is giving away some "freedoms" you never really needed anyway for the good of the community a bad thing? Society is more important than individuals, we Europeans know that.

A society that doesn't protect "unnecessary" individual freedom is not one worth living in. There are two things to note here. First, it's easy to define any sort of freedom as unnecessary. North Korea has done so, for example. Similarly, the idea of primacy of society has justified all sorts of abuses against people by powerful parties who can convenient align the interests of society to fulfill their own interests.

Second, it is better to black list proven harmful action and behavior (I would go for a much more stringent sort of harm, substantial harm against innocent parties who aren't "coming to the nuisance" or otherwise engaging in behavior that deliberately and expectedly exposes themselves to the harm by choice) rather than white list proven harmless or necessary action and behavior. I shouldn't have to prove to society or government that my desired actions are necessary to me. It simply shouldn't be the business of society or government to make that determination, particular since neither has ever shown any competence or impartiality in doing so.

Submission + - SPAM: SNES Game Preservation Project Revived After Package Located

Xenographic writes: Byuu's SNES Game preservation project has been revived after social media attention led to the discovery of the $10,000 package of SNES games at an Atlanta, GA mail recovery center. As you may remember from Slashdot's previous coverage, byuu was working to preserve PAL format SNES games when 100 titles that were lent to him vanished in the mail. It turns out that the shipping label became separated from the package, causing it to fail to be delivered and only through special effort on the part of USPS were they able to locate the package and return it.
Link to Original Source

Submission + - AZ Bill Would Make Students in Grades 4-12 Participate Once In An Hour of Code

theodp writes: Christopher Silavong of Cronkite News reports: "A bill, introduced by [Arizona State] Sen. John Kavanagh, R-Fountain Hills, would mandate that public and charter schools provide one hour of coding instruction once between grades 4 to 12. Kavanagh said it’s critical for students to learn the language – even if it’s only one session – so they can better compete for jobs in today’s world. However, some legislators don’t believe a state mandate is the right approach. Senate Bill 1136 has passed the Senate, and it’s headed to the House of Representatives. Kavanagh said he was skeptical about coding and its role in the future. But he changed his mind after learning that major technology companies were having trouble finding domestic coders and talking with his son, who works at a tech company." According to the Bill, the instruction can "be offered by either a nationally recognized nonprofit organization [an accompanying Fact Sheet mentions tech-backed] that is devoted to expanding access to computer science or by an entity with expertise in providing instruction to pupils on interactive computer instruction that is aligned to the academic standards."

Comment Re:First amendment ? WTH ? (Score 1) 114

The problem with their logic is, of course, that the police aren't forcing anyone to buy an Alexa device.

o.0 That's not a problem with their logic - that's something utterly irrelevant that you've pulled out of thin air.

If I choose to purchase a device that, by design, records everything I say, then I've voluntarily sacrificed my right to privacy in exchange for the benefits afforded by the device.

That's an assertion on your part, not a fact.

It's not the police's fault that I've done so, and they're entirely within their rights to seek a warrant for the information that I've served up on a platter.

Yes... and no. The police certainly are within their rights to seek a warrant to obtain information so long as is it relative to the case. They may not however use warrants to conduct fishing expeditions on the off-chance that information might be found that might be relevant to the case. Though they phrase it in First Amendment terms, that's the heart of Amazon's argument - they police have not established that the recordings are material to the case, and thus have no legal right to make a blanket request for private information.

Comment Re:Maybe (Score 1) 204

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 2) 204

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 Re:TL;DR something you claim is cogent...? (Score 5, Informative) 204

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) 204

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 5, Insightful) 204

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.

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