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User: Yazeran

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Comments · 151

  1. Re:Hmm.. on Odyssey Arriving at Mars Tonight · · Score: 1
    A small correction here, while all closed orbits around an object can be classified as eleptical, not all trajectories arround an object are closed. For a fly-by only, the 'orbit' as seen from the center mass would be a hyperbole.

    Also a circular orbit, would not be classified as an eliptic orbit (Although mathematically it can be described as an elipsis with the small axis equal to the long axis).


    Yours Yazeran


    Plan: To go to Mars one day with a hammer.

  2. Sorry forgot to mention number of users on Too Many Asteroids To Keep Track Of? · · Score: 1
    Sorry i forgot to mention that the above calculation is based on one milion users..


    Yours Yazeran


    Plan: To go to Mars one day with a hammer.

  3. A seti@home style search isn't going to work on Too Many Asteroids To Keep Track Of? · · Score: 1
    Although the idea of a distribted search for NEA's sounds interesting, i do not think it is possible. My concern is primarily that the band-width of the internet is not large enough at present for a project like that.

    In order to find an astroid, you have to compare two images taken of the same piece of the sky some time apart and then look for 'moving stars' (This was the method used to find Uranus, Neptune and Pluto as well). Computers are good for this type of search, but each client must be able to know the orbits of the already known objects so it do not report duplicates. This can be overcome by allowing the client to report those, and then use a central computer to compare new results and discard already known ones.

    The problem comes when a lot of people have to download images and compare. These images must be of the highest resolution for the search to work.
    Analysing an image would not take as long as FFT-analysis of radio-telescope data, as it is basically a pixel for pixel comparison (although this is a bit of an oversimplification). Therefore a LOT of images have to be transmited across the internet.


    Lets make a rough estimate. a high resolution image would be something like 1200x1200 pixels (8 bit greyscale) this is 1.4 MB This can perhaps be compressed to somthing like 300KB. If each user analyses one set of images each day then each user has to download 600KB a day. This corresponds to the server having to transmit 55 megabit/s on average. This might not sound of much, but this is only the raw data, results have to be transmitted back and negotiations between server and client also have to be transmitted.

    I think that this calculation shows that unless some realy smart could be done (or the analysis of the images takes much longer than 1 day on average), a seti@home style distributed analysis would be impractical.


    Yours Yazeran


    Plan: to go to Mars one day with a hammer

  4. Re:How do you tell the difference? on Hello Io, From Galileo · · Score: 1
    I'm a geologist, that's why.. :-)


    Yazeran.

  5. How do you tell the difference? on Hello Io, From Galileo · · Score: 3, Interesting
    I just wonder how the scientists will be able to tell the difference.

    As i recall, if a body is magnetic (induced or otherwise) it will look the same from the outside. Perhaps that is why they want a close flyby to be able to monitor small changes near the surface.

    If anyone knows how you can distinguish between an intrinsic and an induced magnetic field, please step forward and explain.


    Yours Yazeran


    Plan: To go to Mars one day with a hammer.

  6. Re:lots of good stuff to learn on Global Storm on Mars · · Score: 3, Informative
    Well first of all, the atmospheric pressure on Mars is a lot lower than on Earth (as i recall 5 mBar opposed to 1000 mBar) this makes the wind force much lower even for high winds. This low pressure also reduces the size of the particles that can be suspended in the Mars atmosphere and only dust can be suspended for longer periods of time. The effect of this is that wind erosion on any surface on Mars will proceed much slower than on Earth.

    The aerobreaking will also not be influenced, as this takes place at the upper edge of the Mars atmosphere, where no dust particles would be. The breaking do not use a heat shield, so the effective density of the Mars atmosphere at the breaking altitude is small indeed. This is also why the breaking is scheduled to run over many orbital flybys, as a faster breaking would destroy the spacecraft.

    For manned trips to Mars you would use a far lower point of entry for your breaking maneuver, so that the breaking could be achieved in a few flyby's. In that case, however, the spacecraft would have an ablative heat shield as the Apollo modules, or ceramic tiles as the Space Shuttle and even then, the breaking altitude would be far higher than the highest dust particles would reach in a storm.


    Yours Yazeran


    Plan: To go to Mars one day with a hammer.

  7. Solid state manipulation of B-E Condensate on One Step Closer To Quantum Computers · · Score: 3, Interesting
    Well if they can reproduce this, then i belive that we will see proactial applications of this within 5 years. I don't know what these will be, but the fact that they managed to manipulate a Bose-Einstein condensate on a solid state device (well a foil and two gold leads to be sure) makes it more well controlled.


    I wonder what would happen if two such clouds were brought near each other, i suspect that they would repell each other, but would anyone who knows more quantum-physics than me care to explain.


    Yours Yazeran


    Plan: To go to Mars one day with a hammer.

  8. Re:Probes beat a manned mission anyday on NASA Plans On Bringing Back Martian Rocks · · Score: 2
    In some respects you'r right. If the goal for a manned mission was primarily to analyse a few random rocks on Mars, then yes, unmanned probes do this better.

    On the other hand, if your goal with a manned Mars mission is to determine if life ever exsisted on Mars, then nothing beats sending a group of trained geologist up there to walk arround and choose which rocks might be good prospects for finding life. It is the same for terrestial exploration for gold and other minerals, you just cannot be sure if it is there by only using remote sensing or relying on natives to hand you a few rocks form the area. In order to evaluate if there is anything, you gotta have a geologist on site to investigate.

    Similarly for a mission to mars, if you want to find exstinct life or mineral deposits, you gotta have a person with geological knowledge (either a true geologist (best option) or a geologically trained astronaut). Thay did both during the moon landings (several astronauts were trrained in geology, and one real geologist went up there in Apollo 17 a i recall).


    Yours Yazeran


    Plan: To go to Mars one day with a hammer.

  9. Re: Doesn't sound easy... on Putting the Odyssey Spacecraft in Martian Orbit · · Score: 2
    Also the 'scale height' on Mars is larger than it is on earth (by a factor of two i belive). The 'scale factor' is the altitude increase you have to do in order to lower the atmospheric pressure to half as what it was. On earth, this is arround 8 km i think. and on mars it is somewhat larger.

    The implication of this, is that you have a larger 'window' to hit where tha density of the atmosphere is as you want. Not to say that it makes it so much easier considering the time-lag in comunications, but at least it allows for larger uncertainty (I bet the folks at NASA can use all the benefits they can get..).


    Anyways. Cheers for the NASA for their continued effort to put humans into space where we belongs, for even speaking geologically, the earth isn't going to last, and even the sun dies eventually. so if we can awoid blowing each other up, we will have to go to the stars eventually, why not start by going to Mars??


    Yours Yazeran.


    Plan: To go to Mars one day with a hammer.

  10. Danger in energy with no price on British Researchers Say Fusion Is Close · · Score: 2
    Well actually there is some danger in your model. The Soviet Union had such a system (of couse using inefficient coal and nuclear plants). This basic idear of free electricity was the main reason for the technological advantages the US finally got. Research in the US was forced into thinking in terms of saving energy, as you could make money that way. Thus less energy consuming devices like the transistor and other microelectrinic devices was invented, even though a device already exsisted that could do the same (i'm speaking of the vaccum tubes used in old radios and in the first computers (and in the MIG 29 i believe as it makes it capable of operateing during a nuclear war; the soveits thought of that!!, the US didn't untill thay got their hands on one of them.)).

    As the Soviet society had free energy. no incentive was there to develop energy-saving equipment and thus all the consumer-goods and high-end technological devices we use today (like cell phones and portable computers). This is also the main reason that the Soviet Union finally collapsed. The Soviet people also wanted the goods the western world had. Had the situation been the opposite, the Soviet Union would be the worlds only superpower today.

    This is also the main reason that european people uses only half as much energy per capita as in the US. In the US, energy (especially petrol) is much cheaper than in Europe allowing americans to drive in their crappy old chevy's etc. (although they do look cool i must admit).

    Thus as long as there is an incentive to do research into energy-saving technologies, research into those areas will likely be able to spawn lots of consumer-products never thought of before.


    My point is, there should be a price on energy and all other resources, otherwise a catastrophical amount of waste of resources is bound to happen and reaserch might not result in new high-tech consumer products that we all might benefit from.


    Yours Yazeran


    Plan: To go to Mars one day with a hammer

  11. Re:Light sources and heat sinks. on Lighting Technologies For Space Farming · · Score: 4, Informative
    well on the Moon or on Mars you would use sunlight as far as ever possible, as it is cheap and renewable (a term which is as much relevant in space engineering as is is on earth). However, on the Moon (on the surface that is) the 'night' is 2 weeks long! Not that many plants can survive 2 weeks without sunlight.


    On a spaceship or space station other factors have to be considered. In order to use sunlight as light-source, you have to have large windows (if you plan to grow more than a fwe pretty plants that is). Space engineers usually dont like windows for two reasons: One: they are difficult to make so thay are durable and second, they are heavy! The last factor is the most important, as ewry kg of matter sent into space requires at least 100 kg of launch-vechicle (rocket + fuel).


    The last reason for not using sunlight for growing crops in a space station is that spacecraft usually rotate in order to maintain a constant bearing and in order to equalize the heat recieved from the sun. In order to maintain sunshine through the small window you would have to have an elaborate mirror-arrangement outside to direct the sunlight through the window. Such things are expensive to make, and second they also weight something and have to be sent up. Electricity is not so sparce in space, as solar pannels produce electricity. With the new lamps, the power-consumption by the growth lamps is lowered enough, so heat is nolonger a problem.

    All this makes the new lamps worth something.


    Yours Yazeran


    Plan: To go to Mars one day with a hammer.

  12. Re:Glad we have a magnetosphere on Flare Sends A Gigaton Of Solar Detritus Toward Earth · · Score: 5, Interesting
    Actually Venus do not have any magentic field shielding it from the suns particle bombardment. This gives rise to some interesting interactions in the upper atmosphere of Venus.


    The reason for the absence of a magnetic field in Venus is first that it rotates soo slowly (actually it rotates 'backwards' as the orbital angular speed is greater than the rotational angular speed. The second reason for absence of magnetic fields is that the surface temperature is above the Curie tempeature for most magnetic minerals, thus any remanent magnetic field that might have been preserved from Venus earlier life is erased.


    The remanent magnetisation in some ferrous minerals is also the reason for the Moons small magnetic field, evidenting, that the moon had a planetary magnetic field like earth in it's earlier life when the lavalakes (the mares) were emplaced.


    Yours Yazeran


    Plan: To go to Mars one day with a hammer.

  13. Re:should hit sometime in the next couple of days? on Flare Sends A Gigaton Of Solar Detritus Toward Earth · · Score: 5, Interesting
    In theory yes, but remember that this plasma is charged particles and such interact with magnetic fields. The inner solar system is a mess of magnetic fields. Most of these are made by the sun itself, and as such it is not a homogenious field! The sun has no fixed magnetic poles like earth or a bar magnet, thus the solar magnetic field is in a constant state of flux. This insteady magnetic environment will affect the speed and direction of the plasmas ejected from the sun, giving rise to large uncertainties in the arival time.


    Yours Yazeran


    Plan: to go to Mars one day with a hammer.

  14. Re:Black holes are cool on More Evidence On A Milky-Way Black Hole · · Score: 2
    Second, why would the black hole need to be so strong that it distorts the shape of the galaxy?


    The reason for the beformentioned effect is that if a massive object at the center of the galaxy was responsible for the gravitational pull in the stars orbiting it (e.g. the rest of the galaxy) then the stars orbiting close to the center would have to have a orbital path-speed much higher than the stars further out. This combined with the much shorter orbit would result in the inner stars 'overtaking' the outer ones, thus destroying any radial structure in the galaxy. We know such exsist (e.g. the spiral arms) and thus no single big object can account for the gravitational pull.


    If you look at the formulas for celestrial motion (Keplers laws) then this would become obvious. They can be derived from the general gravitational formula: F = G * m1 * m2 / r^2. Where G is the gravitational constant F is the force between the objects (with mass m1 and m2) and r is the distance between them.


    Yours Yazeran


    Plan: to go to Mars one day with a hammer.

  15. Re:U-238 Shells Not an Environmental Hazard on NATO Developing Environment Friendly Weapons · · Score: 2
    You are absolutely right!!.


    Uranium is a common element and can be found in many sources (including concrete, granite and black shales (like those sometimes used as roof material)).

    Remember that this is natural uranium which is MUCH more radiactive due to the decay-products formed during the last 100 milion years since deposition. Depleted uranium is also not realy poisinious as some belive.. You can actually eat it, and the only ill effect would probably be a bad case of digestion (and problems passing metal detectors in airports untill it has passed through.. :-)


    Ordinary lead projectiles are much more poisinous, as lead is soluble (and hence mobile) in acidic water, whereas uranium is not (as long as the water is not too reducing).


    Yours Yazeran


    Plan: to go to Mars one day with a hammer.

  16. Old news.. on The Rise and Fall of Los Angeles · · Score: 2
    Well the fact that Los Angles rises and flalls with the seasons due to changes in the ground water table is not surprising. Mexico city has as far as I recall subcided more than 8 meters during the last 100 years due to excessive water pumping, which has lowered the ground water table quite considerable. Similar for the city of Venice (Italy) where the entire bay has subsided for the same reason (alhtough they seem to have learnt the lesson and have cut down on the water pumping).


    Yours Yazeran


    Plan: To go to Mars one day with a hammmer

  17. Educational use on Magnetic Fluid Art · · Score: 3, Interesting
    Apart from the pretty pictures and funny shapes, fluid like this can be used in education. Children can play with the shapes and at the same time learn something about magnetism (and not only electromagnets will create these shapes), ordinary permanent magnets works just as good. In some instances better, as you cna make multipolar permanent magnets, which makes for some pretty interesting shapes in such fluid.


    Yours Yazeran


    Plan: to go to mars one day with a hammer.

  18. Re:Environmentall Freindly Anti-freeze on Antifreeze Protein Synthesised · · Score: 1
    Well that depends on what sort of anti-freze you talk about. If it is the one used in sprinkler-fluid, then it is ordinary ethanol (at least in Europe.. and biodegradable: Hell Yes :-)


    If you are talking about substitutes for fuel or lubricant oil, then i dont know though, but i would suspect, that ordinary oil would not freexe at normal temperatures (except in the extreme arctic or antarctic environments) and similarly with kerosene or petrol, they are liquid below 0C centigrade as they is, and the additives in those is not for antifreeze, bur rathre for engine performance and durability.


    Yours Yazeran


    Plan: to go to Mars one day with a hammer.

  19. Re:freaky on Radiation Storm Lets You Listen Long-Distance · · Score: 1
    Well this reminded me about when i build an amplifyer myself once. It had a coil-microphone atached, and if i turned the apmplifyer all the way up, i could hear radio-chatter faint in the background. I guess the coil in the mic. acted as an antenna.

    My guess it would be similar phenomena responisble for your acidental pickup of the radio. The only reason for it not happening before is prob. that no station near by transmit at the particular frequency that your amp. aparently is tuned to. (a circuit-board might act as an antenna, and the amplifyer handles the rest, or poor screening of the cable from your guitar allows it to act as an antenna tuned to a specific frequency determined by the capacitance and inductance of the whole system).

    The solar activity mearly resulted in longer range of this station so that you could pick it up. :-)

    Yours Yazeran

    Plan: To go to Mars one day with a hammer

  20. Re:Passing through the plume is important on Geographic Update From Io · · Score: 1
    The plume's density is probably not enough to slow down the spacecraft noticably during its short pass through. Galileo is a large object, and the densities we are talking about here are very low, nanobars of pressure or lower.
    Even though, remember that this amall speed-decrease will be integrated over long time (saying that Gallileo will be slightly behind schedule in the future), probably enough so that it would be possible to calculate the density og the cloud.
    as to the other, you may be right, as i don't know enough about the spectrometers on board to object.

    Yours Yazeran

    Plan: to go to Mars one day with a hammer

  21. Passing through the plume is important on Geographic Update From Io · · Score: 2
    Even though the Gallileo space craft is not designed to directly measure the composition of a gas cloud it passes through, then much can be learned from this pass through the volcanic plume. First of all we will learn the density of the plume (by analysing how much it slows down the space craft).
    Secondly, the composition will be more clearly determined by the spectrometers on board, as more 'close up' measurements of the gasses is possible.
    These data can then be used to calculate the gas emmision from the volcano, and thus we gain more insight on the volcanic porcesses on IO.

    Yours Yazeran

    Plan: to go to Mars one day with a hammer.

  22. Re:unstable on High-temp Superconductors of Silver and Fluorine? · · Score: 2
    Well they do claim that the material has been synthesized, byt so far it has been too unstable to properly investigate. (mainly that you cannot make solids out of them as they disintegrate uppon heating, thus ecxluding sintering as a means of processing). Once they figure out a way to make larger pieces of this, we will know if it is superconducting.

    Yours Yazeran

    Plan: To go to Mars one day with a hammer.

  23. Large detective work ahead on 200GeV Collisions at RHIC · · Score: 3
    It's going to be interesting to see if they can sort out all those sub-atomic particles created by a gold-gold collision. Remember that we are talking of a colision involving approx 500 nucelons (portons and neutrons) here. I'm amazed that they use such heavy atoms, as so many particles are involved. I would guess that if they were looking after the Higgs particle, they would have one hell of a detective work ahead of them.

    But then again, they have those Linux'es to handle that, so i guess they'll manage. One doesn't start something like this unless you are quite sure you'll learn something.

    Yours Yazeran

    Plan: To go to Mars one day with a hammer.

  24. Global torms on mars common on Mars The Dusty · · Score: 4
    Actually dust storms that cover the intire planet of Mars is not uncommon, as the first american probe orbited mars, they at first couldn't get any images of the surface, as a large storm covered the surface. Only the volcanic peaks (olympos mons and the three other volcanoes on the 'Tharis ridge' vas visible due to their huge height. That storm lasted several months if i recall correctly.

    This storm is just a large one. It'll most likely be over in 2 months anyway.

    As to the melting point of CO2, one has to remeember that CO2 doesent melt, it sublimates, as the pressure on mars (and earth) is lower than the critical pressure for liquid CO2. Heating the mars atmosphrere do vaporise more CO2, but it is doubtfull if much more than usual during the southern summer is vaporized.
    atmospheric pressure on mars rises during the summer on the southern hemisphere, as most of the CO2 is bound here and sublimation of CO2 increases the pressure. Similarly in southeren winter, the CO2 precipitates out.

    Yours Yazeran

    Plan: To go to Mars one day with a hammer.

  25. Re:What about the planets? on Stellar Apocalypse Shows Water · · Score: 1
    Except that the stellar winds that boil away the comets would first have hit the planetary system Much closer (and hence hotter) to the star, in efect char-grilling them. Big planaet like Jupiter might survive due to their large mass, but planets like earth would be stripped of any volatile components like atmosphere and vater.

    Planets in other star systems do also not get the benefit of this vapour cloud, as it would be too dispersed before it enters nearby star-systems.

    Yours Yazeran

    Plan: To go to Mars one day with a hammer.