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User: Conor

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Comments · 33

  1. Re:Not Surprising on Tethering Is Exhilarating (With the Nexus One) · · Score: 1

    No, I'm on O2 in Ireland, just turn it on in network preferences and voila! It doesn't even cost me any money unless I exceed my normal download limit for the month.

  2. Re:What's so great about trains? on Obama Proposes High-Speed Rail System For the US · · Score: 1

    Having lived in southern Germany (pretty much the geographical centre of Europe) for about five years, I travelled extensively by train. The rule of thumb is that it is basically impossible to fly anywhere in less than 5-6 hours, city centre to city centre, so any train ride under six hours is faster than flying. This should get you about 800 km, which was enough to reach 11 European Capital cities, including London, from where I lived.

    The price in Europe of train travel is usually pitched slightly below the standard airline fare, i.e. above that of Ryanair. The big advantage of trains is that you can spend six hours sitting at a table with your laptop turned on, no interruptions for security checkpoints, queues, take off and landing etc. On German trains you can usually plug in your laptop too, saving battery life.

  3. Re:also partially incorrect on 9 Laws of Physics That Don't Apply in Hollywood · · Score: 2, Informative

    You mean Cherenkov radiation? This is not due to ionisation, but instead is the optical equivalent of a sonic boom, caused by particles moving faster than the local speed of light. It causes the blue glow seen in containment ponds of nuclear power stations, but is also produced in air by cosmic rays.

  4. Not only biology! on Avoiding the Word "Evolution" · · Score: 2, Informative
    I am an astrophysicist, and I've heard stories of scientists being encouraged to avoid the term 'stellar evolution', which refers to the life cycle of stars, as this has attracted protests from religious fanatics in the USA. It seems any mention of the word 'evolution' in a scientific context is bound to attract unwanted attention.


      On the other hand, the religious nutters do have a point (if completely unwittingly), since it modern astrophysics contradicts the bible version of creation just has much as modern biology does!

  5. Re:Wonder what Mordehai Milgrom will be saying on Astronomers Make Important Dark Matter Discovery · · Score: 1

    Dark matter does not absorb all electromagnetic energy! It merely floats around without emitting much electromagnetic energy. There's a big difference. It does interact gravitationally however, which is how it was identified.

  6. Re:Unintended Consequences on Nanotube Paint Blocks Cell Phones on Demand · · Score: 1

    Don't worry, the nanotubes will explode in the heat and then you'll be able to use your cellphone just fine!

  7. Re:Not /. editors' fault... on Microsoft to Storm Linux Strongholds · · Score: 1

    On the subject, how should Bill Gates' eye (or God's for that matter) contain a moat? Isn't it more likely that it might contain a mote?

  8. Re:Turn in your Geek License on Free ASL Computer Technology Resources? · · Score: 1

    I don't know that tag , does that work a bit like ? ;-)

  9. Re:Buy a grammar primer on What Can You Do With $100? · · Score: 1

    I agree, everyone knows gift is an adjective!

  10. Re:DOE would have no interest in CF on DOE Report on Cold Fusion · · Score: 1

    Did you read the report? It clearly states that the composition of the review group included theoretical and experimental nuclear physicists, materials scientists and electrochemists. The accusation that these people were biased because 'they stand to lose a lot by CF's successes' is easily made and pretty damned insulting to someone's integrity, so you could at least try to get your facts right!

  11. Re:Shell of debris approaching on Origin of Cosmic Rays Revealed · · Score: 3, Informative

    First question, yes, it is possible to do that, especially for younger SNRs (up to a few hundred years maybe). For older ones, such as RXJ 1713 its harder as its more difficult to discern expansion.

    The second point refers to SN 1987a, which was observed to explode 17 years ago (hence the name).

  12. Re:Shell of debris approaching on Origin of Cosmic Rays Revealed · · Score: 3, Informative

    RXJ 1713-39, the SNR in question, is believed to about 1kiloparsec away, which corresponds to 3260 light years. When we say it is believed to be 1000 years old, that means it would have been seen at the earth 1000 years ago. It is actually possibly 4000 years old, but may be older. It is quite hard to determine the distance to these things unless one saw them explode.

    What we see now is 1000 years after it exploded, so we just call it 1000 years old for simplicity.

    The shell should be too old and dispersed to emit gamma rays by the time it reaches the earth.

  13. H.E.S.S. and cosmic rays on Origin of Cosmic Rays Revealed · · Score: 5, Informative

    Since I work for this experiment, I guess I should try to clear up a few points which have been discussed here.

    A Supernova remnant (SNR) is a very rapidly expanding bubble of hot gas, created by the explosion of a massive star. It is thought that the shock wave caused by these expanding bubbles in our galaxy accelerate surrounding hydrogen gas to very high energies, which then become the cosmic ray protons which we see at the earth today. Protons form the bulk of the cosmic ray flux between MeV and EeV energies, and at least up PeV energies they seem to be formed in our Galaxy, probably by SNRs.

    The SNRs are really light years across, the ones we see are generally in the local quadrant of our galaxy, thus are really not far away in the cosmic scale of things. Happily not close enough to fry us though! Cosmic redshift does not occur within our galaxy, by the way.

    We detect gamma rays at very high energies by looking at their interactions with the upper atmosphere. The gamma rays themselves do not generally penetrate to the ground, we measure the Cherenkov light emitted by the shower of charged paticles which stem from the gamma ray interaction.

    One reason gamma rays are interesting is that they , like other photons, travel directly to us from their source, so we can use them to make pictures of what the source looks like. We believe in this case that the gamma rays are produced in the supernova remnant by interactions of the accelerated protons, and thus are a tracer which proves the existence of the comsic rays at the SNR, and thus that SNRs generate cosmic rays.

    The particles which pass through us every day are mostly muons, which are by-products of the interaction of cosmic ray protons with the atmosphere.

    More information can be found at:

    http://www.mpi-hd.mpg.de/hfm/HESS/HESS.html

  14. Sony T610 and Linux on Best Bluetooth Capable Cell Phone? · · Score: 2, Interesting

    Can anyone recommend good software to use with Linux and this phone? Something like Gnokii would be great, I used it with my old Nokia 6210 and found it very useful.

  15. Re:How to find out the location of a jammer? on How to Jam a Worldwide Satellite TV Broadcast · · Score: 5, Informative

    According to company website they use radio interferometry. To do this they need another (relatively) nearby satellite with a similar transponder, which also sees some interference. Then they measure the arrival time difference between the signals bounced from the two satellites, using this they can then triangulate the position to within a few miles.

    If you pay them lots of money they'll send out helicopter
    (assuming its not in Cuba!) to find the exact antenna causing the problem.

  16. Re:Parasites... on Why Alien Species Thrive · · Score: 1

    Is this what allowed the invading alien culture to almost wipe out the indigenous people? The fact that they weren't constrained by such parasites as law enforcement and a sense of ethics?

  17. DVD regions in France on DVD Region Encoding on Verge of Collapse? · · Score: 1

    A friend of mine bought a DVD player last year in France from a major high street retailer, who offered a handy de-regionalising service to their customers. You left it in to the customer service desk, they charged you 30 euros and you got it back a few days later fixed. Seemingly this is perfectly legal in France. Does this happen elsewhere?

  18. Re:more non-spoilers on The Lone Gunmen Are Dead · · Score: 1

    Sorry, at least two of these are wrong. Anyone spot them?

  19. Re:Are these really near misses? on Stealth Asteroid Misses Earth · · Score: 1

    It might make it clearer if you compare the Earth to the central bullseye on dartboard, which is roughly 1 cm across. In that case this asteroid would be a dart that missed by 36cm, ie it didn't even get close to hitting the board!

    It is quite valid to neglect the effect of the Earth's gravity on the asteroid, as it is moving far too fast to be deflected enough to hit the earth.

  20. Re:Attack the cause. on First International Mine Detector Robots Competition · · Score: 2, Informative
    There is an international treaty banning the use of Land mines.For details see www.icbl.org . Here is and extract:

    Each State Party undertakes never under any circumstances:

    To use anti-personnel mines;

    To develop, produce, otherwise acquire, stockpile, retain or transfer to anyone, directly or indirectly, anti-personnel mines;

    To assist, encourage or induce, in any way, anyone to engage in any activity prohibited to a State Party under this Convention.

    Each State Party undertakes to destroy or ensure the destruction of all anti-personnel mines in accordance with the provisions of this Convention. There are 50 countries in the World who have not signed this treaty, they include:

    Afghanistan

    China

    Cuba

    Iran

    Iraq

    North Korea

    Libya

    Myanmar (Burma)

    Vietnam

    Yugoslavia

    The United states of America

    The USA is also one of the World's biggest producers and exporters of Landmines.

    So if you really want to do something to get rid of these terrible weapons, which mostly kill and maim innocent people, then write to your Congressman!

  21. Re:Temperature Inversions on Salt Lake City from LandSat · · Score: 3, Informative

    A temperature inversion occurs when a layer of cold air is trapped below a layer of warmer air. Thus the air temperature increases with altitude, which is not usually the case. This is often due to a high pressure region in the winter, which traps the air close to the ground. Since the cold air is less bouyant than the warm air above, the normal convection process stops working and a build-up of pollutants occurs. A strong horizontal wind is needed to clear out the cold, dirty air from the city.

  22. Re:English is the language of business on English, The Global Internet Language? · · Score: 1

    I'm an Irish astrophysicist working in France on a French /German project. The language of the collaboration is English, so all major meetings are in English. Here in France we all speak French at local meetings, even if there's a majority of native English speakers present. In Germany they speak English if there is even one native English speaker there. Cultural differences, I guess.

  23. Electrons and wave functions on Electron Fission · · Score: 1

    The electron is the wave function. They are one and the same thing. It means nothing to describe the electron as a point charge in space, if you split the wave function you split the electron also. This is the very basis of quantum mechanics, wave - particle duality.

  24. Re:Slow and huge.. on Netscape 6, PR 3 Released · · Score: 1

    Troll. Pathetic too. Ignore

  25. Re:This is Pud just playing around on F*ckedCompany.com For Sale - On eBay · · Score: 1

    >$9,000,000 (and rising) is a lot of traffic! I'd say he'll go through with it...