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User: barakn

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  1. Re:Optical illusion? on A Symmetrical Cosmic Red Square · · Score: 4, Interesting
    First of all, I'd suggest looking at this higher resolution image, available from this page with other fascinating graphics. I would agree that the more-or-less horizontal component of the central X (the sides of the hour glass) is in the same direction as the two "horizontal" components of the stars' hexagonal rays (by coincidence, I presume). However the vertical part of the central X does not point in the same direction as any of the hexagonal rays. This may be a simple demonstration of how an hourglass doesn' have hexagonal symmetry, but more importantly it suggests the hourglass isn't produced by the same process as the hexagonal spikes.


    Having said that, there are some faint hexagonal spikes created by the central object, but they are much fainter than the hour glass shape..


    I wouldn't use the term "quasar-like" because the word quasar is an acronym for "quasi-stellar radio source" and i don't think this object is the source of many radio waves

  2. Re:Optical illusion? on A Symmetrical Cosmic Red Square · · Score: 5, Informative

    There are some artifacts in the image. Notice the stars with 6 rays. The rays are created by support structures holding the secondary mirror of the telescope in front of the primary mirror. The fact that the square doesn't have hexagonal symmetry argues for its existence as a real object.

  3. Dupe on Bad Math Causes Explosion at CERN Collider · · Score: 1

    The reason that "[t]his story might seem strangely familiar to you" is that both stories refer to the same event.

  4. Re:Coand effect on Combined Hovercraft and Helicopter · · Score: 4, Interesting

    It's interesting that you bring that first link up. The second link, Coanda Effect: Understanding Why Wings Work, is from no less than Jef Raskin, the father of the Mac. It contains a fallacious argument on why the Bernoulli effect can't explain the lift generated by a wing, which he claims he first derived as a child. It contains some child-like assumptions, the most grievous being the assumption that the ratio of the chord lengths (distance over the wing versus under the wing) is the same ratio as the speed of the air over the wing versus under. This implies that two air molecules that separate at the front of the wing, one going over and one going under, will meet at the back edge of the wing, as if joined by some invisible rubber band. In reality the ratio of the speeds is larger than the ratio of the chords, and the top molecule reaches the back long before the bottom one does. This link to a different page on the same website as the first Coanda fallacy link, shows the airflow using smoke pulses and does a great job of describing what is going on.

  5. Re:caves a good spot to land on Large Caves Found on the Surface of Mars · · Score: 1

    this discovery could allow humans to colonize mars
    Yes, because it would be impossible to create an artificial cave.
  6. Re:kinda funny, really... on Serious Magnet Failure at CERN's New Accelerator · · Score: 1

    I was referring to the kinetic energy (Earth frame of reference) of the cosmic ray just before it enters the top of the atmosphere, therefore I was not only referring to the energy of the most energetic particle, I was referring to the energy of the only particle. I'm not sure what point you were trying to make. Perhaps you got confused and thought I was referring to after the cosmic ray hits something and generates an enormous shower of particles. If we were going to count those there would be a lot more but of lower energy.

    Typical anonymous coward, going off half-cocked.

  7. Re:kinda funny, really... on Serious Magnet Failure at CERN's New Accelerator · · Score: 4, Informative
    Such chicken-little-the-sky-is-falling hysteria is unwarranted. The collision energies in the LHC are expected to be 14 TeV when using protons. The flux of cosmic rays of energy greater than 1 TeV is 100 per year per square meter of the Earth's surface. That works out to about 1.6 billion such cosmic rays per second around the globe. The collision energies in the LHC are expected to be 1,150 TeV for lead. The flux of cosmic rays of energy greater than 100,000 TeV is one per century per square kilometer of the Earth's surface. With a surface area of ~500,000,000 km^2, that's 5 million cosmic rays per year with energies at least a hundred times greater than the LHC collision energy.

    Nature has been performing experiments in our atmosphere for 4.55 billion years at energies much higher than we could hope to attain in a collider. If it was possible for a black hole spawned in one of these event to swallow the Earth (or whatever other nightmare scenario you've envisioned), it would have already happened and you wouldn't be around to discuss it.

    Reference 1
    Reference 2

  8. Re:The greying of slashdot on Organism Survives 100 Million Years Without Sex · · Score: 1

    The geek age range has been relatively constant throughout the ages. It's just that previous generation of geeks was more comfortable with calculators than computers, and the generation before that more comfortable with slide rules than calculators.

  9. Re:The shape bothers me... on Possible Large Impact Crater In Nevada · · Score: 2, Interesting

    The Sudbury crater is over 1.8 billion years old, and thus has had plenty of time for tectonic forces to deform its shape. According to this site the crater "was affected by orogenic deformation that led to shortening of the Structure by large-scale thrusting and folding." It was probably circular when first formed. The thing about low-angle impactors is that they have to pass through more atmosphere than a impactor on a vertical trajectory, and are thus more likely to be destoyed in an airburst, like the Tunguska event in Siberia, or skip off the atmosphere, like the event over the western U.S. in 1972. Of course the Black Rock crater, if it exists, may also have started circular but stretched into an ellipse by normal faulting in the area.

  10. The "Magic Box" Demonstration on Humans Hardwired to Believe in Supernatural Deity? · · Score: 4, Insightful

    I find the "Magic Box" demonstration uncompelling. Scott Atran, the perpetrator of the demonstration seems unwilling to think outside of the box, so to speak. Perhaps the individuals harboring "negative sentiments toward religion" are reluctant to place personal possessions or body parts into the box not because they secretly believe the superstitious claptrap they've just been told, but because they now suspect the crazy person who just told them that nonsense to have boobytrapped the box. The answer to the article's question "If they don't believe in God, what exactly are they afraid of?" is that they are afraid of Scott Atran.

  11. That's not the Fermi Paradox on Fermi Paradox Predicting Humankind's Future? · · Score: 1

    Fermi never said anything about civilizations colonizing the entire galaxy. Story submitter should have read the wiki article he/she included as a link.

  12. Not so informative on Cheap, Safe, Patentless Cancer Drug Discovered · · Score: 1

    DCA is used to increase the metabolic rate of mitochondria, not lower it. The whole point is that cancer uses an alternate metabolic pathway that doesn't use mitochondria.

  13. Re:Dogma shoots the US in the foot...again on Cheap, Safe, Patentless Cancer Drug Discovered · · Score: 1

    Perhaps you're forgetting that your employer is footing most of the insurance bill.

  14. Ostrisized? on Viva Piñata Apparently 'For Girls' · · Score: 1

    Ostrisize, v. - to stretch to the height of an ostrich. Ostrisize, adj. - as tall as an ostrich. And thus ostriches join the pantheon of familiar objects used as describe the dimensions of unfamiliar objects, e.g. VW Beetles used as a unit of volume.

  15. The most convenient form of id on Maine Rejects Federally Mandated ID Cards · · Score: 2, Interesting

    ...would be some sort of RFID chip injected under the skin, or maybe something lower tech.. perhaps a serial number tattooed on the arm. We should make one of those standard.

  16. Re:Kurt Vonnegut Jr. on The Sierras of Titan · · Score: 1
    I am quite interested to see if there is a way to engineer bacteria to break methane down into oxygen or some other gas that we could potentially exploit to make oxygen.
    I'd be very interested to see if there's a way to engineer bacteria to perform nuclear reactions too, but it's not going to happen.
  17. Re:Lots of water on Ancient Crash, Epic Wave · · Score: 1

    Oceanic crust recycles itself much faster than continental crust. You'd have a hard if not impossible time finding ocean crust older than 200 million years, but there are areas of continents over 3 billion years old. Thus one should expect to find less than 3/4 of all impacts in the oceans.

  18. Re:I thought it sounded familiar on Ancient Crash, Epic Wave · · Score: 1

    Perhaps they didn't like the fact that your journal entry said "no reg required" when, in fact, registration is required.

  19. Re:Astroids.. pew pew pew on NASA Proposes Manned Asteroid Mission · · Score: 1

    Some might argue that asteroid miners would be in danger of being fried by solar storms without the advance warning provided by 3d solar imagers. In fact, since asteroid miners might be on an asteroid on the opposite side of the sun from the Earth, there currently isn't enough coverage of the sun's far side. Even with the STEREO mission, 1/6 of the sun's surface will not be visible. I suspect at some point there will be a solar observatory in a halo orbit around L3.

  20. Re:you'll get answers on Global Warming Debunked? · · Score: 1
    If you think about it, this seems to imply that the Greenland had just been warmer than it currently is, and that it was starting to freeze up again when Eric discovered it.

    Only if you are going to ignore the rate of precipitation. Perhaps it has been warming, and the warmer air with its increased moisture capacity has been dumping more snow, hence glacial advance. Colder = more ice is a little naive.

  21. They clean themselves on Mars Rover Reaches Victoria Crater · · Score: 2, Interesting

    Various mechanisms involving dust, wind, steep slopes, etc. have been proposed, see this article.

  22. Disregarding the privacy issue on Google to Use PC Microphones to Listen In? · · Score: 2, Interesting

    there's still the fact that this alleged Google software would be eating up a lot of CPU cycles and some network bandwidth. There's too many negatives from the consumer's point of view, and I think Google is too smart to try this.

  23. Re:What about extra heating needed? on The Light Bulb That Can Change the World · · Score: 1

    Americans use as much if not more electricity for cooling than heating, and even in areas where heating is necessary it's not necessary all year long. Since lights are usually at or above eye level more of the heat is wasted on the empty space over everyone's head. Plus electricity is more expensive to heat with than other energy sources.

  24. Re:Reeves is not all he's cracked up to be on Another New Tomb in the Valley of the Kings? · · Score: 4, Interesting
    FTFA, with the part you omitted highlighted in bold:
    Reeves was falsely accused of involvement in antiquities smuggling and his permit was revoked. In August 2005, he was officially cleared of any wrongdoing by Egypt's Supreme Council of Antiquities (SCA), though not allowed to return to his work in the Valley.
    Perhaps they just didn't have enough evidence.
  25. Re:Even the name admits it's hoax?!? on One Year Until Phoenix Mars Mission Launch · · Score: 1

    Yes, which is why whenever you start talking about the number 6 and Unix your Bolivian friend thinks you're saying "Yes, I am going to Uyuni."