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User: RockDoctor

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  1. Re:Lazy Westerners on Colombian Airline Wants To Make Passengers Stand (yahoo.com) · · Score: 1

    your [load] shift in one direction and the whole balance of the aircraft is thrown out of whack.

    The word you're looking for is "trim". The trim of any mobile structure is something that needs to be considered under both intended and unintended conditions, whether that's an airplane in the air, a ship at sea (see for example, the Herald of Free Enterprise (~190 dead) or the Ocean Ranger (87 dead, IIRC), or a vehicle on the road (every driver who loses their license for driving with an insecure load).

  2. Re: That's nothing! on Colombian Airline Wants To Make Passengers Stand (yahoo.com) · · Score: 1

    Doesn't America have lunatic asylums for idiots like the GP? Or are those the Canadian and Mexican borders I'm thinking of?

  3. Re: Memories... on 23 Years Of The Open Source 'FreeDOS' Project (linuxjournal.com) · · Score: 1

    So did my PDP-11. Which I got rid of to another enthusiast 20-some years ago.

  4. Re:Same age as ReactOS on 23 Years Of The Open Source 'FreeDOS' Project (linuxjournal.com) · · Score: 1

    ReactOS, however, has always been on a moving target [...] Thus they're always behind and will never be able to achieve a complete stable product.

    That's exactly what I expect from the name "React[to the changes in the target you're trying to track]OS".

    Which is no denigration of the system - I've not actually got round to dropping a spare HDD into a machine to try it - but simply tells me that they know and accept that they're going to always be playing catch-up.

  5. Re: Not to state the obvious, but on Ask Slashdot: Is Logging Long Hours a Recipe For Burnout or the Only Way To Get Ahead? (bloomberg.com) · · Score: 1

    Henry Ford and others that are not in any way suspect of wanting to do good for their workers.

    Not that I'm a fan, in any way, shape or form, of the loathsome system of exploitation called capitalism, but Ford did do some things for his workers which were relatively good. But they were designed to rebound to his eventual benefit. I'm thinking specifically of his paying them a relatively good wage without requiring fully-apprenticed skills from them. That meant that medium-skilled people could het to earning a reasonably good wage.

    But Ford's self-serving cut from this seeming generosity was that it made it possible for his workers to afford to buy their product, and for Ford's marketing department to use this cohort of blue-collar workers buying cars to present it as a new "normal".

  6. Re: Not to state the obvious, but on Ask Slashdot: Is Logging Long Hours a Recipe For Burnout or the Only Way To Get Ahead? (bloomberg.com) · · Score: 1

    So that's the last posting ever by Anonymous Coward (deceased)?

  7. Re:Closed source security software on Should Kaspersky Lab Show Its Source Code To The US Government? (gizmodo.com) · · Score: 1

    I honestly agree with this. I think they should be demanding the source to all security relevant products

    The word "security" is superfluous in this sentence. Where does "security" start? Or stop?

  8. Re:Doesn't belong here on Seeking YouTube Fame, A Teenager Kills Her Boyfriend (arstechnica.com) · · Score: 1

    Leo Tolstoy wrote War and Peace which was certainly quite a fatter book.

    I'm slightly surprised that it has got this far without someone suggesting a single volume edition of George Martin's "Game of Thrown's" quad-pent-oct-ology, or however many books it's up to at the moment. That should stop some serious shit.

  9. Re:I grew up in a hole in the ground in the desert on Iranian City Soars To Record 129F Degrees: Near Hottest On Earth in Modern Measurements (washingtonpost.com) · · Score: 1

    but if it costs money you can bet it wasn't met.

    Proper weather stations require maintenance, which requires money. If nothing else, the calibrations on the instruments must be checked regularly - does the dry thermometer read the same as a suite of check thermometers? Has a rat eaten the mesh off the wet bulb (or, for that matter, shat on it)? Is there a boot-shaped ding in the rain gauge?

    Then the reading techniques need to be checked. For day-shift and night shift observers. So you've already guaranteed that your calibration checker has spent a day on site, excluding travel costs. That'll be the thick end of a kilobuck for wages, transport and accommodation already. Yearly.

    I just did a mental count of the airfields in the county with sufficient "general aviation" to probably need a weather station, and got 22. 3/4 of them on the mainland, and no problem to get to by road. The remaining quarter are in outlying island groups (including 2 airfields with a scheduled mile-and-a-bit route between them) and would take around half of the effort for a calibration cycle. I wouldn't do that job for less than £30,000, which is whatever kilobucks.

    Short version : weather stations cost money to build, equip, and maintain.

  10. Re:Eddies on Something Big Is Warping Our Outer Solar System (futurity.org) · · Score: 1

    You always wind up with eddies in a hydrodynamic simulations

    Yes. Also in reality.

    and it is a bad assumption that the origins of the solar system was non-chaotic.

    Why do you believe that planetary origin modellers don't include chaos in their models. After all, they do used thousands of processor years of computer time to do exactly that. Can you give me an Arxiv (i.e. open) link to these hydrodynamic papers that don't include chaos. You do realise that they run ensembles of these models precisely to search for chaotic effects and to understand the limits of that chaos.

    How much mass, and how tightly spiked a mass-distribution function are you proposing? And what is the dynamic lifetime of that distribution of particles before they're either dispersed by orbital noise or collapse into a single body? (I'll give you a hint : it's been tried ; such accumulations disperse over periods of a few hundreds of orbits, or they collapse. They don't persist for significant fractions of the age of the Solar system. People have done, uhh, hydrodynamical simulations.)

  11. Re:Black Hole? on Something Big Is Warping Our Outer Solar System (futurity.org) · · Score: 1
    There is no such thing an a "full-scale black hole" (and it's implied "half-scale" and "double scale" black holes. If there is enough mass in a small enough volume that the escape velocity is greater than the speed of light in a vacuum, then it's a black hole. It's binary condition - black-hole or not-black-hole ; no intemediates (and as far as we know, no superlatives).

    Maybe some time in the distant past, this system had two stars. Singular star systems are supposedly less common than binaries.

    If it was a star, then it had nuclear fusion, and we'd have seen it while trying to figure out how to crawl out of the oceans and breathe air. If it was too small to have nuclear fusion, then ... well, that's when it gets pretty tricky, because all sorts of complicated effects like cloud formation complicate the loss of heat from such a "brown dwarf", or "planet". some theorists are arguing over whether such an object could be seen in near--IR or far-IR, or what instrument designs might see it ; while others are searching with existing technology instead of trying to decide which new technologies might be needed to observe it.

    In the realm of stars, mass is everything. If it's smaller than the Sun, it'll have a lower temperature and use it's fuel more slowly, living longer. The brightness (and fuel-use, and lifetime) depends quite steeply on the mass. If it's larger than the Sun, it'll be brighter than the Sun ; it's not brighter than the Sun, therefore it's smaller than the Sun. Considerably smaller.

    Or some other lesser stellar remnant that's burnt out,

    Considering the lifetime issues just discussed, that could not be an object that was born at the same time as the Sun. Which means it must have been captured into orbit around the Sun, after the formation of the Sun and it's co-existing planets. It's is very hard to do that at all, and models of the capture process eject pretty much all of the planets. We're here ; therefore that didn't happen. (A much smaller object than a star - a planet like Neptune, for example - might be captured, but even so it's hard to see how that could have happened without throwing everything smaller than Saturn out of the Solar System. We're here; that almost certainly didn't happen.)

    The universe is, at this scale, simple than you think. Simpler than Hollywood likes, that's for certain. Simpler than Discovery Channel producers like too.

  12. Re:Black Hole? on Something Big Is Warping Our Outer Solar System (futurity.org) · · Score: 1

    Second power of distance.

  13. Re:How do they do this? on Something Big Is Warping Our Outer Solar System (futurity.org) · · Score: 1

    (I recall that the outer planets were detected before they were known this way)

    Neptune was found this way, but that was likely coincidence. The early estimates of Uranus's mass (and the other planets, principally Jupiter's) were off by a few percent, which made Le Verrier's estimate for the location of Neptune essentially unjustifiable. But he got lucky, and Galle found the planet at the predicted position. Repeating Le Verrier's calculation with the revised Solar System geometry after the transits of Venus in the 1870s and 1880s just did not work - Neptune was again in the "wrong place". So ... there must be another perturbing planet out there, and off went Percival Lowell on his planet-hunt, which culminated in Clive Tombaugh's 1930 discovery of Pluto.

    Come the space age, and actually putting objects of known mass through the solar system (the Mariner series, the Pioneers, the Voyagers) and we got direct measurements of the masses of the major planets, and that's when the initial errors in Uranus's position reduced to within observational uncertainty, and Neptune's too. Pluto, frankly, doesn't matter. The currently proposed PlantNine (Brown-Batygin2016) doesn't matter for Neptune and inwards ; neither does the Mars-ish proposed planet. Too small, too far away.

    Intuitively the angles involved must be far smaller than typical mechanical tools could measure so how do they do it?

    Well ... I'll give you a hint : they don't go down to the hardware store and buy a protractor. It's custom builds all the way, for professional "astrometry" work. There was a book on my shopping list for some years, which I never found time to buy or read, called "Dividing the Circle" ... here it is, of you've got the thick end of £100 and a couple of weeks of reading time to devote to it.

    What do you consider "typical tools"? I work with steering oil wells, and for 30+ years people have been making their direction and inclination measurements to an accuracy of 0.1 degrees of arc (6 minutes of arc) ; we have to correct for how much a steel pipe 200mm outside and 75mm inside sags when suspended horizontally between two supported points 20m apart (the approximate size of the tools ; smaller tools, lower accuracy). This is utterly routine. For amateur telescope work, you get to within a half-degree (of arc) or so of your desired object, then start to "zoom in" using the patterns of relative star positions from your "finder chart". (Compiling those stellar atlases is a different kettle of fish ; Google for the technical publications on how the Hipparcos and Gaia satellites work for state-of-the art.) You measure positions on the sky relative to other stars ... and have to check for ones with known relative ("proper") motions compared to other stars. And every few decades, you have to buy a new set of star atlases. The standard (to amateur level ; professionals only work from online databases) work is Uranometria 2000 ; the "2000" part of the publication's name is the "epoch" to which the atlas was drawn ; the previous edition was done in 1950, the previous in 1900 ... it is literally never-ending. Until you use the databases, which can produce a star map accurate for your date and time of observing.

  14. Re:Pluto? on Something Big Is Warping Our Outer Solar System (futurity.org) · · Score: 1

    Wasnt Pluto reinstated as a planet not long ago (again)?

    No. Alan Stern and some others from his team have made the argument again, and been soundly ignored by the rest of the planetary science community.

    He's a respected worker (PI on New Horizons, for instance), so he'll get peer reviewed and published, but that doesn't mean that he'll carry the consensus with him.

    I'm not a planetary scientist myself, but I do follow the field quite closely. When @plutokiller (Mike Brown, Caltech) killed Pluto, I was personally more in favour of a mechanics-based criterion (is it round, +/-10%?). But that would have made Uranus P6, Ceres P7, Neptune P8, Vesta P9, Pallas P10, Pluto P11, Chiron P12, and then the KBO discovery-factory started up with a couple of dozen more "planets" since then. If you think that's a preferable situation, then you too can make that argument.

    Since then, I've read and digested Hal Levison's arguments, summarised at https://www.boulder.swri.edu/~... ; they make sense and I've decided to accept the IAU and accretion/ ejection (~="clearing) argument. Pluto is not a planet, it's a "dwarf planet", or a "small body" (there's still some argument over terminology.

    Alan Stern, respected though he is, wants to have the topic of his career's study, Pluto, classified as a planet, along with the rest of the "big boys". Sorry, Alan ; no can do. Pluto has been pushed around all it's life, and will be pushed around for the rest of it's life, until the heat death of the universe.

  15. Re:Mars mass object inside 100 AU? on Something Big Is Warping Our Outer Solar System (futurity.org) · · Score: 1
    Whether it remained on an eccentric orbit depends very much on when it happened, and therefore on how many other objects there were for it to interact with. When there are a lot of objects with a range of masses, there is a statistical tendency to sow down the larger objects, and to circularise their orbits.

    I agree that an extra-Solar origin would be considerably more unlikely than a within-Solar origin, but it's hard to rule out an extra-Solar origin.

  16. Re:Mars mass object inside 100 AU? on Something Big Is Warping Our Outer Solar System (futurity.org) · · Score: 1

    If its a kuiper belt object, then it must be huge to have that much mass, because of its low density.

    As the mass goes up, the material near the core gets compressed. Which is why, despite very similar compositions, Earth has a density of 5.51 (g/cc or tonnes/cu.m) and Mars (1/10 Earth mass) is 3.93 (same units) while the Moon (1/82 Earth mass) is 3.34.

    Triton and Pluto and Charon are the furthest out bodies for which I have figures (I've really got to put some more of the KBOs into my data base) : Triton Mass = 1/279 MassEarth, density 2.06 ; Pluto 1/455 and 1.83 ; Charon 1/3927 and 1.65. So ... for a Mars-mass KBO, I'd estimate density at around 2.5 (I don't have an EquationOfState calculator for water-ices either. If someone asks a question like this several more times, I'll have to make one.) Which would give a radius of (3* mass/ (density* 4* pi))^ (1/3) = 3943 km compared to 3396 km radius for Mars and 1160 km radius for Pluto. So, it should be about 10 times as bright as Pluto at Pluto's range, and at 100AU (2.5x Pluto's semi-major axis) approaching twice the brightness of Pluto. So, why hasn't it been seen before?

    Or it could be a rocky object, like Vesta or Mercury, but then its hard to explain how it got to be so far from the sun.

    If it were rocky, then it would have about the same radius as Mars, and so the same reflective area, and again, it would have a comparable brightness to Pluto.

    OK, I'll grant that those estimates are pretty dependent on my guesstimate for the EquationOfState for water-ice, and so the bulk density for the putative planet. But that density isn't going to be lower than Triton, and it's not going to be higher than for Mars (which would imply "rocky"), and the constraints still leave it being comparable in brightness to Pluto, within a factor of the variable albedos of known KBOs. (Hell, just look at the brightness variation imaged on Pluto and Charon!)

    I don't see a problem with scattering (say) a Mars-mass rocky oligarchic core from the inner Solar System out to the Kuiper belt. Stopping it once it gets there ... a bit harder (PlantNine as envisaged by Brown-Batygin 2016 might help here!). Dynamic friction could even out it's orbit after a few billion years. I don't see this being a show-stopper.

  17. Re:Not again! on Something Big Is Warping Our Outer Solar System (futurity.org) · · Score: 2
    Strange, but I was swapping messages with Konstantin just yesterday and he's of the opinion that the evidence is moderately stronger than this time last year. Which is how I read Friday's (or was it Thursday?) paper on the subject too. Planet Nine (sense : Batygin-Brown 2016) is still pretty firm. 3 to 4 sigma.

    Regardless of which , with this proposed "planet" being around 1xMars mass, it's also around 0.1xEarth mass and 0.01xP9(BB2016). Literally, it and it's effects would fit in the error bars of the P9(BB2016) parameters. Both could be correct simultaneously.

    But, if this newly proposed planet were to exist with the described parameters, then we've already found plenty of considerably dimmer dwarf planets in comparable orbital parameters, which raises the question of why it hasn't been seen yet.

    Ethan StartsWithABang knows his science perfectly well, and seems to have found a balance between advertising revenue from clickbait and keeping his sanity and dignity. Since I loathe the interface of Medium, and it never works with advertising and scripts disabled, I don't know this particular page, but if I were you, I'd read it at least three times to check what he actually says, rather than what you want to hear said.

  18. Re:I grew up in a hole in the ground in the desert on Iranian City Soars To Record 129F Degrees: Near Hottest On Earth in Modern Measurements (washingtonpost.com) · · Score: 1

    there are no official weather stations there. All the official measurements were taken miles away in Odessa or other shit-hole towns they happened to put weather stations in or around.

    Many "official" weather stations are (or were) on airfields, because the requirements (for temperature and wind speed measurements in particular) require soil not asphalt, plans, not bare soil, and a certain distance from buildings or relief or trees greater than X m tall ... which doesn't dictate an airfield, but if you fulfil those conditions, there's a good chance that your site would make a good airfield.

    Were there any (temporary) airfields established in your area as the Germans invaded, or as the Soviets pushed them back? That would be a good place to try to site an "official" weather station.

  19. Re:Past the boiling point of water? on Iranian City Soars To Record 129F Degrees: Near Hottest On Earth in Modern Measurements (washingtonpost.com) · · Score: 1

    Rock Off!

  20. Re:Past the boiling point of water? on Iranian City Soars To Record 129F Degrees: Near Hottest On Earth in Modern Measurements (washingtonpost.com) · · Score: 1

    And don't even start me on pints, ounces, fluid ounces....

    "Pint" is a measure for beer ; ounces are what you buy your cannabis in ; outside American recipes, I've never seen fluid ounces used. Ever. So, from context, you know what unit the measurement is in.

    I had a American once recite a ditty taught him by his father, that "a pint [is] a pound / the world around". When of course, a pint is a pound and a quarter. Because a gallon weighs ten pounds.

  21. Re:Past the boiling point of water? on Iranian City Soars To Record 129F Degrees: Near Hottest On Earth in Modern Measurements (washingtonpost.com) · · Score: 1

    Catering to the most local audience - where many of the ads are most relevant to - makes sense.

    Slashdot has adverts? I've literally never seen one, and I've only been using an ad-blocker for the most-recent three or four years of my usage.

  22. You can survive well if you can sweat, but if humidity approaches 100%, you're dead.

    If you'd been on the Gulf coast (Persian, not the one around Cuba) when the tail end of the monsoon swept in and took the humidity from the low 20s to the high 40s over a matter of hours, you'd know this from personal experience.

  23. "Squirrels" taking down large sections of town on a regular basis is pretty pathetic.

    It's actually a piece of creative marketing. The "squirrels of outage" are almost certainly human-chosen reductions in preventative maintenance, so that when a circuit-breaker trips because a squirrel is frying, the equipment doesn't successfully reset once the squirrel is atomised. Or the control room 200 miles away has it's ability to manually re-set the breaker still sitting in the accountant's department, filed under "insufficient ROI".

  24. Re: They're still going to want more money on There Is a Point At Which It Will Make Economical Sense To Defect From the Electrical Grid (qz.com) · · Score: 1

    in Texas... the grid is needed to provide enough electricity to run A/C units and well pumps, which isn't really doable via solar.

    What is it about those two consumers of electrical power that make it intrinsically un-doable with solar?

    If the power requirements are very high, then you might need to have both rooftop and front-lawn solar panels, but that is not un-doable.

  25. Re:Israeli Immigration on Short of IT Workers At Home, Israeli Startups Recruit Elsewhere (reuters.com) · · Score: 1
    Regardless of the translation, your first claim was that "veterans of the IDF can carry a gun", but then both translations make it that it's "veterans discharged at [NCO or officer] rank" who can carry. I don't know the details of the IDF structure, but I doubt that the second category is 1-in-5 of the IDF, and may be as low as 1-in-10.

    Which is not that far different from American statistics - although there's an average of about 1 gun per person, the actual number of gun owners is somewhere between 1 in 5 and 1 in 10, averaged over the whole country.

    Neither is particularly encouraging. I come from a country with an annual murder count comparable with New York City, with around 10 times the population. But I've only seen a real gun on three occasions outside the airport.