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Alien Solar System Much Like Ours

MrGort writes "Wired News reports that British astronomers say they found the first sun-like star with a giant gas planet in an orbit similar to Jupiter's, which leaves plenty of room for worlds like Earth and Mars. This system is a quick 90 light years away. The similar solar system to ours means that this gas giant could attract most of the debris, allowing smaller planets closer to the sun to develop like ours did!"

130 comments

  1. 90 Million Light Years? by Markus+Registrada · · Score: 1, Funny
    Wow, what a great telescope! If I could see that well, I could spot a quark on Pluto from here without even squinting.

    Of course the article said 90 light years, which is way too far to walk (or drive) anyway. (We are 8 light minutes from the sun, and it would take your whole life and part of your kids' to drive that far.)

    1. Re:90 Million Light Years? by Anonymous Coward · · Score: 1, Funny

      If you were going fast enough it wouldn't be so long (for you anyway, nevermind earth people).

  2. 90 Million L.Y.? by Anonymous Coward · · Score: 0

    That's 50 time the distance to Andromeda. Methinks somebody misplaced a few zeros....

    1. Re:90 Million L.Y.? by trompete · · Score: 2, Insightful

      I think the article actually said 90 LY, which isn't that far at all, considering that our galaxy is 100,000 LY across.

    2. Re:90 Million L.Y.? by Anonymous Coward · · Score: 0

      no no. It is 90 Light years.. I agree.. It isnt Far in relative terms.. because every now and then we talk about planets, galaxies and so forth.. So many millions and on occasion billions of light years away....

      Maybe those aliens we have come from this solar system...

  3. patent by pyrrho · · Score: 4, Funny

    This other solar system, it does know that we've patented the planetary creation process... right?

    10 billion years of back license royalties... wehooo!

    --

    -pyrrho

    1. Re:patent by ChadN · · Score: 5, Interesting

      You know, this reminds me of the setup of a book by John Varley, called "The Ophiuchi Hotline". It starts off with us learning that humanity started receiving transmissions from space, in the direction of the Ophiuchus constellation. We started receiving it about 400 years prior, and have been decoding peices of it ever since. Of the amount that can be decoded and translated, we've learned about medicine, space travel, computers, etc. All kinds of amazing technology. No one knows who is sending it, or why.

      But a repeating message has appeared, taking up more and more of the transmission. Our hero is summoned to a meeting where he learns that some of this repeating message has ben translated.

      In summary, it reads: "Payment for service is overdue. Please remit immediately, or severe consequences will result."

      The book plays out from this premise.

      Let's hope we never have to deal with intergalactic IP issues.

      --
      "It's overkill, of course. But you can never have too much overkill." - Anonymous Slashdot Coward
    2. Re:patent by brusstoc · · Score: 1

      Yeah, but the intergalactic lawyers will tie up the proceedings in court for a few revolutions of the galaxy which will eat up all of the royalties. We'll never see any of it.

  4. This is not Star Trek by rudy_wayne · · Score: 4, Insightful

    >> This system is a quick 90 light years away.

    This is the problem with the whole "is there life elsewhere in the universe" debate. I call it the "Star Trek Syndrome". People have gotten so used to movies and TV shows where space ships go zooming all over the galaxy that they have lost any understanding of the enormous distances involved.

    There probably are planets out there with intelligent life -- maybe lots of them -- but they are so far away that it is impossible to have any contact with them. You can debate all you want about whether or not there's life out there, but you can't change the math.

    If we could build a spacecraft capable of a speed of 16 Million Miles per Hour (which we can't -- that speed is far, far beyond any technology we have or have even dreamed of) you could reach Pluto in a few days, but it would take 360 years to reach that system that is only "a quick 90 light years away". Even trying to communicate via radio -- we would send a message and it would be at least 180 years before we got a reply.

    1. Re:This is not Star Trek by Anonymous Coward · · Score: 2, Funny
      I think Mister Smarty-Pants here hasn't heard of wormholes.

      'Eddies,' he said, 'in the space time continuum.'

      'Ah. Is he? Is he?!

    2. Re:This is not Star Trek by Beryllium+Sphere(tm) · · Score: 4, Interesting

      >beyond any technology we have or have even dreamed of

      We've dreamed of some pretty impressive things. For example, the Alcubierre drive (http://www.wikipedia.org/wiki/Alcubierre_drive). It has some [facetious]minor engineering problems like requiring negative energy density and more total energy than exists in the universe[/facetious], but it's a warp drive that satisfies the equations of general relativity. Faster than light, and physically legal.

      Off topic, did the headline of this story strike anyone else as being like a headline from The Onion?

    3. Re:This is not Star Trek by burns210 · · Score: 1
      " There probably are planets out there with intelligent life -- maybe lots of them -- but they are so far away that it is impossible to have any contact with them."

      someone is sounding like a pessimist... tisk, tisk. 100 years ago, a couple guys were playing around with this idea of flight, that kinda took off didn't it? Space travael is a big step, give it time.

    4. Re:This is not Star Trek by Christopher+Thomas · · Score: 4, Insightful
      There probably are planets out there with intelligent life -- maybe lots of them -- but they are so far away that it is impossible to have any contact with them. You can debate all you want about whether or not there's life out there, but you can't change the math.

      "The math" also says two things:
      • We can most definitely contact systems within a few hundred light-years by radio. We'll need an array of phase-locked transceivers in space to do it, but it's not difficult or even horribly expensive to do. Contact by optical carrier depends on us building very large interferometric telescopes, which is a tougher engineering challenge but can also be done.

        Communication occurs at the speed of light, so round-trip time to 90 light-years is 180 years, and one-way time is 90 years.

      • This is useful because anyone who can hear our signals and generate signals for us to hear in return is almost certainly far more advanced than we are.

        Modern humans have existed for about 30,000 years. Human civilization has existed for on the order of 6000 years, depending on who you ask and what you call "civilization". If the lifespan of an alien technological race is longer than this - and it will be, especially once it decentralizes (makes colonies not on the same easily-bombed planet) - then, of the stretch of their civilization's existence where they can hear and respond to us, the segment where they are more advanced than us is much longer than the segment where they are less advanced than us. This makes it likely that _if_ we find someone to contact, they're in the "more advanced than us" stage.

        This makes communication, even with a multiple-lifetime time lag, worth it.


      This discussion overlooks the impact of any future technology that would confer either extreme longevity, or the ability to store and reconstruct a human mind-state/personality. In the first case, slower-than-light travel between the stars becomes feasible because we have the patience for it, and it doesn't take that large a chunk out of our lives. In the second case, we can be sent at the speed of light as data, with no subjective time elapsing en route, to be reconstructed at the other end.

      In conclusion, communication is both possible and worthwhile even without FTL travel or exotic technologies.
    5. Re: This is not Star Trek by menscher · · Score: 1
      Also, information can move faster then light in the right conditions. For instance, if we built a long stick to europa or whatever, we could tap out morse code before any light could arrive

      Incorrect. The tapping is basically a vibration. And that vibration will travel no faster than the speed of light.

    6. Re:This is not Star Trek by tiled_rainbows · · Score: 2, Informative

      Re. slower than light travel - if you get fast enough (i.e. a sizable fraction of c), then, even if it takes dacedes to get where you're going, time dilation will mean that far less time passes for the crew of a spacecraft - so, if you're going fast enough, a trip of 90 light-years, say, could be accomplished within the natural lifetime of the crew without FTL travel.

    7. Re: This is not Star Trek by amorsen · · Score: 1

      To be precise, the vibration travels at the speed of sound in that medium. (That is practically the definition of the speed of sound...) This will always be slower than the speed of light in vacuum, no matter which medium.

      --
      Finally! A year of moderation! Ready for 2019?
    8. Re: This is not Star Trek by HurlyBurlyMarley · · Score: 0, Troll

      You talking to me? The vibration doesn't have to happen on earth, it happens where the stick hits....If my stick is approximately 800,000,000 km long (long enough that it hits the target) and I move it an inch or so that it strikes Europa in a way that it makes a tone, all that matters is that it can be interpreted as dot-dot-dot, dash-dash-dash, dot-dot-dot. That's possible without the vibration going through the stick.

      I think you are misinterpreting me. I'm not saying use the stick as a telephone wire, in which case you are right, but I'm saying extend the equipments reach and bypass the slow link(electrons in this case). I hope this amuses you...

      Flash Gordon just ended :(

    9. Re:This is not Star Trek by turgid · · Score: 3, Informative

      I agree with you that we shouldn't be too pessimistic, however the Wright Brothers' flight was more of an engineering challenge than a scientific one. They required no novel physics to accomplish their feat, only the application of known physical laws. It will be possible for us to explore our own solar system using known physics by using nuclear propulsion (fission and some day fusion) and even solar sails. However, travel to other stars in less than a human life-time in our frame of reference will require super-luminal speeds. There is no physics known yet that will allow us to achieve this. So, interstellar travel will be a lot harder for us to achieve than the Wright Brothers' first powered flight.

    10. Re:This is not Star Trek by turgid · · Score: 1

      We've already been sending out artificial radio waves from Earth for around 100 years. If there was intelligent life there that had sensitive enough radio detectors they may already have detected us.

    11. Re:This is not Star Trek by sk0pe · · Score: 4, Insightful

      Yes, the Wright brothers managed to apply proven physical laws through engineering. However, in the 1600's, those laws of physics (specifically Bernoulli's principle) were not theorised, let alone proven. Peope did, however, dream of flying like the birds.

      The same applies to space flight now. We can dream it, but we can't figure out how to do it. Some day, a bunch of different people will come up with a bunch of theories on "super-luminal" travel, then set out to prove their theories. One of them will be proven.

      Soon after that, someone will apply that "proven" law of physics (as the Wright brothers did), and a short time later interstallar travel will be like catching a plane is now - nothing out of the ordinary.

      Unfortunately, it's not likely to be in our lifetime. (Oh, that it were!!)

      --
      Tempus fugit sub anesthesia.
    12. Re:This is not Star Trek by Gyl · · Score: 2, Informative

      True, there may eventually be laws that allow for faster than light travel (wormhole anyone?) But the Wright borthers had birds as examples that flight was possible. We don't have any physical evidence of super-luminal travel being possible.

    13. Re:This is not Star Trek by Gyl · · Score: 1

      It's true, 90 light years is quite a distance for us to travel or communicate. But, compared to the rest of the galaxy, or universe, 90 light years is quite close. If life is to be discovered within, say, 200 years it will likely be at that sort of range.

    14. Re:This is not Star Trek by turgid · · Score: 1
      Unfortunately, it's not likely to be in our lifetime. (Oh, that it were!!)

      Oh, that is were, indeed. We can console ourselves somewhat with things like SETI and the fact that with advanced nuclear technology we should be able to explore the Solar System. There must be so much there waiting to be discovered. I only wish those with the money and the brains would get on and do it!

    15. Re:This is not Star Trek by Zan+Zu+from+Eridu · · Score: 1
      Some day, a bunch of different people will come up with a bunch of theories on "super-luminal" travel, then set out to prove their theories. One of them will be proven.

      Assuming Einstein was right with his theories of relativity, super-luminous travel or even travel at the speed of light is a major no-go: travelling at the speed of light means instant displacement for the traveller; for the traveller it takes 0 (zero) seconds to move any distance at the speed of light.

      So Einsteins relativity doesn't keep you from travelling astronomical distances if you reach speeds close to c, it actually helps you to do so. The big problems are a) the wellknown fact that time for the starting point and the finishing point of the journey goes a whole lot quicker than it does for the traveller (or more accurate: time for the traveller goes slower the faster he moves); and b) the human body can only endure acceleration of about 1g for prelonged periods.

    16. Re:This is not Star Trek by Christopher+Thomas · · Score: 3, Informative

      Re. slower than light travel - if you get fast enough (i.e. a sizable fraction of c), then, even if it takes dacedes to get where you're going, time dilation will mean that far less time passes for the crew of a spacecraft - so, if you're going fast enough, a trip of 90 light-years, say, could be accomplished within the natural lifetime of the crew without FTL travel.

      There turn out to be practical problems with this. Any craft that carries its own fuel with it - including the more practical breeds of antimatter drive - will be limited to a crusing speed of about 0.1-0.2C by the specific impulse of their fuel. The only thing that could approach speeds at which time dilation would be significant is a beamed core antimatter drive (that uses the charged particle shower from an antiproton annihilation as the reaction mass), but that requires unrealistic amounts of antimatter (positrons are easy to make, but antiproton synthesis is very inefficient, and will remain so unless new physics is discovered).

      In principle, some kind of sailcraft driven by a stationary laser or maser array could reach relativistic speeds, but the array would be very expensive to build and very large (we need to focus on a planet-sized sail at a range of many light-years). It would also work wonderfully as a weapon capable of melting cities to slag at a range of hundreds of AU (or even light-years, depending on configuration), so I suspect non-proliferation agreements would prevent it from being built in the first place.

      In short, the only hope for relativistic travel at less than colossal cost is new physics.

    17. Re:This is not Star Trek by tiled_rainbows · · Score: 1

      "Any craft... will be limited to a crusing speed of about 0.1-0.2C by the specific impulse of their fuel"

      It's been far too long since I read a non-fiction book with spaceships in it, but can't you (in theory) propel a spaceship by shining a very powerful light out of the back, using the photons themselves as the reaction mass? Then could you get nearer to c?

    18. Re:This is not Star Trek by Christopher+Thomas · · Score: 3, Informative

      It's been far too long since I read a non-fiction book with spaceships in it, but can't you (in theory) propel a spaceship by shining a very powerful light out of the back, using the photons themselves as the reaction mass? Then could you get nearer to c?

      You can, but the problem is generating the light in the first place, and the fact that light has a lousy ratio of momentum to energy (it has to be very, very bright to generate significant thrust).

      Most light sources that are bright enough to move a ship at any reasonable acceleration (e.g. fusion bombs wrapped in other matter or just shining on a shield block that can tolerate gamma rays) waste matter - the energy to mass ratio of a fusion bomb is much worse than that of the photons you're driving the ship with. This means you'd be better off just using a magnetic bottle to deflect the plasma resulting from the fusion explosion, and you'd still end up with specific impulse too low for relativistic flight.

      A light source that doesn't ablate or otherwise lose mass has to be relatively dim (either a hot block of solid matter or a confined plasma ball), which means getting anywhere will take an extremely long time.

      The forms of light propulsion that I've seen considered involve generating the light somewhere else (e.g. a laser array) and just reflecting it off the craft's sail. You still have a drive that's horribly inefficient energy-wise, but the energy source doesn't have to travel with the craft.

      For reference, power to thrust is 3e8 W/N for a photon drive (energy to momentum ratio is C for photons).

    19. Re:This is not Star Trek by weston · · Score: 1

      a quick 90 light years away

      I'm going to guess that the submitter actually knew that 90 light years isn't quick by any sort of standards we have for travel here on earth, but rather said that as a mix of tongue-in-cheek-humor, and some somewhat well-deserved optimism. It really could have been much, much farther, as far away as 90 light years really is.

    20. Re:This is not Star Trek by resignator · · Score: 1

      i have seen at least one theory that didnt involve the speed you travel or distance. It relied on pulling space toward you kinda like folding a blanket using gravity. The problem was the amount of energy needed to create this affect. The idea that there are other ways to travel other than just accelerating from one point to another is not that unbelievable to me.

      --
      "At first, we thought it was just another snake cult."
    21. Re:This is not Star Trek by barawn · · Score: 2, Insightful

      ... assuming that said craft does actually carry its own fuel (which you limited yourself to, but...)

      That's, of course, not the only kind of craft: ramscoop ideas have been around for a while, and while they're not exactly "production quality" ideas, there's nothing fundamentally killing them. We'd just have to figure out how to do fusion much better than we do now - which is not exactly new physics - it's new engineering. We'd also want to get the hell past the heliopause, to interstellar space. Ramscoops can easily build up to relativistic speeds, because, well, their fuel is free.

      Especially when you get to decent Lorentz factors things start to work in your favor: space is compressed, so the interstellar density becomes higher (drag isn't exactly an issue, because presumedly your ramscoop is strong enough to drag in material even at a decent spatial compression) and so you get more fuel as you go faster.

      It's not an issue of viability (because it is viable), it's simply scale. A ramscoop type ship would probably need to be large, and the "initial speed" required to start up the reaction is probably high as well, though this depends on exactly how good fusion technology becomes.

      Also, as a brief comment, antiproton synthesis is very difficult, but antiproton storage is much easier than positron storage, because they're charged and heavy, so once you cool them, you lose very few. So again, production of large quantities of antiprotons is not difficult at all - it just takes time.

      Your final conclusion, though, is definitely right. Relativistic travel = huge cost (in 2003 dollars! note that economies of scale and necessity can help here. Automated antiproton factories, etc.: thank god for that tremendously huge fusion generator sitting next door pumping ungodly amounts of energy out all around us.)

      So, finally, calling them "practical problems" may be a bit harsh on them. It's just that, as a species, we're not motivated enough to do it.

      Maybe, just maybe, if we ever find a planet which we have a good belief that we could live there, that'll be enough of a motivation for some country to do it.

    22. Re:This is not Star Trek by sbaker · · Score: 4, Insightful

      What's different about our society looking to develop super-luminal travel compared to people in the 1600's thinking about heavier-than-air flight is that whilst there were no known scientific laws that would enable a heavier-than-air craft to stay aloft, there were no laws to prohibit it either. They had birds, insects and bats flying around all over the place - all demonstrably heavier than air. They knew this was an achievable goal.

      With faster-than-light travel, we have a very different situation. He have actual scientific laws courtesy of that Einstein guy that show that you cannot accellerate an object up to the speed of light without consuming infinite energy . Those laws also indicate extreme difficulties with even the concept of something travelling FASTER than light (if you ever got going faster than light, it would take infinite energy to avoid travelling infinitely fast - and getting to a nearby star at infinite speed is MUCH harder than doing it at subluminal speeds.

      Then, we also have no examples of super-luminal objects to point at and say "Ha! Those laws must be wrong".

      That's an entirely different (and much more depressing) situation than the situation in the 1600's. They could look to a simple child's kite and imagine a hang-glider with a motor replacing the force provided by the kite-string. They could see birds doing that exact thing - taunting us with the ease of it all.

      We have no similar thing to look towards - and one of the greatest minds of the last century showed us clear mathematical proof that this isn't going to be an easy matter.

      --
      www.sjbaker.org
    23. Re:This is not Star Trek by Scott+Carnahan · · Score: 1

      ramscoop ideas have been around for a while, and while they're not exactly "production quality" ideas, there's nothing fundamentally killing them.

      Dialogues concerning the viability of ramscoops tend to follow a "death by a thousand cuts" pattern, mostly because whenever someone finds a reasonable obstruction to their practicality, someone else will propose a wildly unrealistic and ad hoc remedy, saying it could be plausible one day with future technology. Perhaps a better description of the situation would be that ramscoops are fundamentally dead, but that there are also many people who insist that the technology is merely ... pining for the fjords.

      It's not an issue of viability (because it is viable), it's simply scale.

      Scale tends to dictate viability of technologies. The article here describes several problems with the ramscoop design. One of them, involving radiation loss, looks like it would be overcome with a ramscoop about the size of the sun. This is not viable.

      As far as I can tell, practical interstellar travel requires "new physics" (read: don't hold your breath).

      --
      "Your notation sucks!" -- Serge Lang (1927-2005)
    24. Re:This is not Star Trek by Anonymous Coward · · Score: 0

      Does antiproton synthesis require new physics,
      I thought it was largely an engineering problem?

      Similarly inefficiencies in the production push
      up the economic cost, which makes it less
      practical, but by the time you come to address
      how to cross interstellar space from a
      practical perspective we'll presumably have
      mastered interplanetary travel, so power sources
      shouldn't be a major issue.

      As far as I know serious scientists are still
      contemplating 1g acceleration for flight duration
      making it practical to visit planets within a few
      dozen lightyears (if you are prepared to leave
      everyone you know behind in space and time -
      or take them with you).

      Several major assumptions go into assessing the
      feasibility of interstellar flight, one of the big unanswered
      ones being what is the galaxy made of. Until we
      can adequately explain what the bulk of the mass
      of the galaxy is, I suspect spectulating on
      whether we'll ever flip through it at a
      significant fraction of the speed of light is
      premature.

      I'm not sure I'd want to find the missing fifth
      essence by running into it at 0.2c!?

      Yes there are practical problems building the
      technology we need, but I don't believe there
      are any obvious show stopping physics.

      Indeed time dilation seems to almost too good to
      be true to the would be interstellar traveller.

      Strangely some of the major issues which I don't
      think will change, are related to human nature.

      Whilst some entrepid spirits will try to travel
      would many people really want to travel so fast
      and far that they would become an anachronism
      in their own life time?

      Of course last time travel to colonise a place
      was dangerous, and unpleasant we sent convicts,
      and/or religious extremists, and America and
      Australia didn't turn out too bad in the end.

    25. Re:This is not Star Trek by Christopher+Thomas · · Score: 1

      Does antiproton synthesis require new physics, I thought it was largely an engineering problem?

      Producing antiprotons efficiently requires new physics. Producing them _inefficiently_ is just a Small Matter of Engineering, and is already done on a semi-routine basis (though at quantities many orders of magnitude lower than would be needed for spacecraft fueling).

      The problem is that when you create particle/antiparticle pairs, you get far more light ones than heavy ones. The fact that protons and antiprotons are composite particles doesn't help either (there's no particular reason to get a proton instead of a neutron or a bunch of mesons at those energies).

      The numbers I've heard batted around for the best efficiency we can expect synthesizing antiprotons are in the 1e-4 to 1e-6 range. Considering that that's a factor of ten thousand to a million more than the vast rest energy stored in the antimatter in the first place, and you see why it gets expensive.

      New physics could help by giving some magical way of turning energy into proton/antiproton pairs at near-perfect efficiency (i.e. getting mostly protons and antiprotons, not other junk or energy lost by other means). The key word here is "magic", in that there is no feasible mechanism for this selection that I know of.

      Before anyone brings it up, yes, current antiproton generation proposals already consider tuning the source beam energy to the most favourable ranges for production.

      Similarly inefficiencies in the production push up the economic cost, which makes it less practical, but by the time you come to address how to cross interstellar space from a practical perspective we'll presumably have mastered interplanetary travel, so power sources shouldn't be a major issue.

      Power plants will never be free to build or maintain, which means that energy will never be free. Likewise, the antimatter production facilities will have a finite maintenance lifetime over which cost is to be amortized. Thus, I don't expect antimatter to ever be cheap, or the cost of an antimatter-powered probe's fuel supply to be anything less than "colossal". It may still get built, but it won't be cheap for the forseeable future.

      As far as I know serious scientists are still contemplating 1g acceleration for flight duration making it practical to visit planets within a few dozen lightyears

      As cruise velocities would be much lower than C, and travel times in the decades, there is no reason to boost at C. As lower-thrust engines are usually easier to design, they'd be favoured. The only high-acceleration proposals I've heard about were unmanned sailcraft (a maser driven craft, in this case).

      Several major assumptions go into assessing the feasibility of interstellar flight, one of the big unanswered ones being what is the galaxy made of. Until we can adequately explain what the bulk of the mass of the galaxy is, I suspect spectulating on whether we'll ever flip through it at a significant fraction of the speed of light is premature.

      The "missing mass" doesn't seem to interact with things via the electromagnetic force. If it did, it would be opaque (in at least some bands) and be much easier to detect. As far as anyone can tell, dark matter would not impede spacecraft in any way except gravitationally (and that only on a galactic scale).

      Yes there are practical problems building the technology we need, but I don't believe there are any obvious show stopping physics.

      The show-stopping physics is the fact that the specific impulse required for relativistic flight is too high to attain with anything but a beamed-core antimatter drive. Anything else is limited to about 0.2c or lower if it carries its fuel with it. Beam-powered craft are another issue, as described in my previous message.

      A beamed-core antimatter drive has a show-stopping cost issue, for reasons described above.

      Whilst some entrepid spirits will try to travel would many peop

    26. Re:This is not Star Trek by Christopher+Thomas · · Score: 2, Informative

      That's, of course, not the only kind of craft: ramscoop ideas have been around for a while, and while they're not exactly "production quality" ideas, there's nothing fundamentally killing them. We'd just have to figure out how to do fusion much better than we do now - which is not exactly new physics - it's new engineering.

      Ramscoops are fundamentally killed by drag.

      Consider a ramscoop to be a special case of a magnetic bottle. In a conventional magnetic bottle, matter leaks through "loss cones" at the pinch points of the mirrors. The tighter the constriction (i.e., the greater the field increase compared to the field in the middle of the bottle), the narrower the loss cone and the less material leaks out.

      A ramscoop, on the other hand, works by passing material through the pinch point, hopefully with enough compression to fuse in the process. The problem is that, given the fact that the field is much larger than the coils used to generate it, the pinch point is very narrow indeed, and very little material gets through the loss cone (most is just deflected). So, you get lots of deflection and very little fusion to provide thrust. Bye bye dreams of ramjets.

      Making the throat of the ramjet wider means less compression, and lack of fusion.

      Using an active compression scheme (pulsed conical field coil, for instance) requires coils the size of the field - either heavy enough to make the ramscoop useless, or small enough to capture almost no fuel.

      In summary, ramjets in practice don't seem to work very well.

      Any relativistic craft launched would be sailcraft or other beam-driven craft of some kind, as that's the only way to provide enough energy to the craft.

      Relativistic travel = huge cost (in 2003 dollars! note that economies of scale and necessity can help here. Automated antiproton factories, etc.: thank god for that tremendously huge fusion generator sitting next door pumping ungodly amounts of energy out all around us.)

      Neither solar collectors nor antiproton factories are free, which means that the cost will always be significant. In practice, it will be colossally expensive to produce antiprotons for the forseeable future, for reasons outlined in detail in another post.

      A phase-locked maser array would probably be the cheapest method for driving a relativistic craft, but has political problems outlined in my previous message.

    27. Re:This is not Star Trek by Mycroft_VIII · · Score: 1

      Unfortunately 'folding space' dosen't help. the problem isn't with the acceleration per-se. But rather with getting from point a to point b in less time than light in a vacum could make the same trip through normal space/time. How you get there isn't as important as when. Naturally there is a lot more to it than that, and any language other than math pretty much gaurantees a bad explantion, but the gist of it pretty much holds.
      fair warning IANAP just a fairly well read interested spectator.

      Mycroft

      --
      https://signup.leagueoflegends.com/?ref=4c3ed6600b6ea
    28. Re:This is not Star Trek by JoeRobe · · Score: 2, Insightful

      They required no novel physics to accomplish their feat, only the application of known physical laws.

      However, travel to other stars in less than a human life-time in our frame of reference will require super-luminal speeds. There is no physics known yet that will allow us to achieve this.

      True, but it should be pointed out that for decades after that, most scientists thought it was physically impossible to break the speed of sound in an aircraft. There was no physics that allowed > Mach 1 speeds to be achieved. With time, that theory was also proven wrong.

      --
      The best way to predict the future is to invent it.
    29. Re:This is not Star Trek by smallpaul · · Score: 1

      I find it disturbing that futurists tend to presume that the benefits of communication outweigh the risks. Okay, an Independence Day scenario is not likely. But how unlikely? 1 in 10 chance? 1 in 100? 1 in 1000? 1 in 10000? What is an acceptable risk? (we do, after all, have at least one potentially valuable commodity down here: a world with flora and fauna that will be alien and novel to them) And what would we get from them? Technology? I'm not against technology but it isn't the be-all and end-all. I think that we should consider carefully before we encourage them to investigate us.

    30. Re:This is not Star Trek by Suppafly · · Score: 1

      This is useful because anyone who can hear our signals and generate signals for us to hear in return is almost certainly far more advanced than we are.

      There is no proof of that. The whole hoping aliens are smarter than us is a bad assumption. If it took so long for life to evolve here, it would probably take just as long if not longer in other conditions.

    31. Re:This is not Star Trek by turgid · · Score: 2, Insightful

      There was no physics that allowed > Mach 1 speeds to be achieved
      Not true. Newtonian physics allows Mach 1 to be broken. Einsteinian physics does not allow c to be broken (or to be achieved with rest mass).

    32. Re:This is not Star Trek by cellocgw · · Score: 1

      True, but it should be pointed out that for decades after that, most scientists thought it was physically impossible to break the speed of sound in an aircraft. There was no physics that allowed > Mach 1 speeds to be achieved. With time, that theory was also proven wrong.

      Can you document this? I'm aware of engineering studies showing what the difficulties would be in exceeding Mach1, and the valid concern that vibrations from the shock wave could damage improperly designed craft, but have never read an accepted (for its time) study that said Mach1+ was impossible.
      My guess would be that this is similar to the incorrect claim that scientists "proved" bumblebees can't fly, when what was proved was that they couldn't fly if their wings were rigid (and they are not rigid).

      --
      https://app.box.com/WitthoftResume Code: https://github.com/cellocgw
    33. Re:This is not Star Trek by cellocgw · · Score: 1

      So far as the question of fuel capacity vs terminal velocity, two words: "Tau Zero", by Poul Anderson.

      --
      https://app.box.com/WitthoftResume Code: https://github.com/cellocgw
    34. Re:This is not Star Trek by calyxa · · Score: 1
      b) the human body can only endure acceleration of about 1g for prelonged periods.

      uh, I hate to break this to you, but you're experiencing an acceleration of 1g right now, and you have been most of your life...

      -calyxa

      --
      Decay! Decay! Decay! -Helium
    35. Re:This is not Star Trek by resignator · · Score: 1

      what i was basically trying to point out was that there are many theories that await to be discovered. If you would have asked someone 200 years ago how to get to the moon I am sure you would have just got a confused look. Admittedly, the "folding space" theory wasn't the best example but just becasue we cannot conceive of a way to travel to far off galaxies now does not mean it cannot happen.

      --
      "At first, we thought it was just another snake cult."
    36. Re:This is not Star Trek by Zan+Zu+from+Eridu · · Score: 1
      uh, I hate to break this to you, but you're experiencing an acceleration of 1g right now, and you have been most of your life...

      Exactly, the human body was "built" for 1g; you can't put humans in a spaceship and accelerate with 2g for 25 years or you'll arrive with a dead crew. Even if we had the technology to reach relativistic speeds; we can't accelerate human bodies a lot, so manned interstellar travel would still take generations (for the crews).

    37. Re:This is not Star Trek by Anonymous Coward · · Score: 0

      Actually we have the knowledge of photons which obviously travel at the speed of light, so we know light speed travel is possible, we just don't know how to do it with our available technology. And as for superluminal speeds the Alcubierre Warp Drive and hypothesized Wormholes provide the ability to travel at FTL speeds. So FTL travel will come in time.

    38. Re:This is not Star Trek by The+Unabageler · · Score: 2, Insightful
      have actual scientific laws courtesy of that Einstein guy
      last I checked it's still the General Theory of Relativity.
      --
      perl -e '$_="\007/4`\cp%2,".chr(127);s/./"\"\\c$&\""/gees; print'
    39. Re:This is not Star Trek by JoeRobe · · Score: 1

      I'm aware of the limits of Newtonian and Einsteinian physics. Back in the day, however, it was believed (or so I hear - someone else wants documentation, which I'm currently looking for) that you could not accelerate an object past the speed of sound in the medium that the object is in. That doesn't mean >Mach 1 speeds were believed to be impossible, because they were aware of speeds of meteorites as they entered our atmoshere. The belief was supposedly that you couldn't accelerate a body past the speed of sound on earth in our atmosphere. For airflight, that meant mach 1 at the time.

      --
      The best way to predict the future is to invent it.
    40. Re:This is not Star Trek by balaam's+ass · · Score: 2, Interesting

      Photons have no rest mass. You do. Figure out how to get rid of your rest mass, and you can travel at the speed of light...

      The limitation on faster than light travel can be thought of as a requirement to preserve causality, if all reference frames (freely-falling ones, if you like) are regarded as equally good. Thus FTL travel would violate causality in the standard picture of relativity. But perhaps someone will show that a preferred frame exists. Even so, all alternative models I'm aware of which allow for a preferred frame (e.g. bimetric gravity) require causal behavior to stay within the "light cone."

      It's true that Alcubierre's warp drive spacetime doesn't have any causality violation or other funny business going on locally (which is all relativity refers to), however, as has already been noted above, the warp drive requires matter with a negative energy density. Such matter can be defined mathematically but is physically meaningless. FYI, Alcubierre himself regards the solution as an interesting toy but not something to be taken seriously from a physical standpoint.

      Wormholes also require negative energy. See above. Various people keep working to push the requirements so you need less negative-energy-matter. I say if you need any at all, the whole thing makes no sense.

    41. Re:This is not Star Trek by Squiffy · · Score: 1

      >>>This system is a quick 90 light years away.

      >>This is the problem with the whole "is there
      >>life elsewhere in the universe" debate. I call
      >>it the "Star Trek Syndrome". People have gotten
      >>so used to movies and TV shows where space
      >>ships go zooming all over the galaxy that they
      >>have lost any understanding of the enormous
      >>distances involved.

      >It's true, 90 light years is quite a distance
      >for us to travel or communicate. But, compared
      >to the rest of the galaxy, or universe, 90 light
      >years is quite close. If life is to be
      >discovered within, say, 200 years it will likely
      >be at that sort of range.

      I agree that this must be what the original submitter had in mind. The statement, "90 light years is quite close," could even be considered an understatement. If you compare a 90 light year distance to the size of our galaxy (which is itself of negligible size compared to the observable universe) you'll see what I mean. It's like a flea on a dinner plate.

    42. Re:This is not Star Trek by Christopher+Thomas · · Score: 1

      So far as the question of fuel capacity vs terminal velocity, two words: "Tau Zero", by Poul Anderson.

      This craft used a Bussard ramscoop. There have been multiple messages in this thread explaining why they turn out not to work. For practical field configurations, drag greatly overwhelms fusion-produced thrust.

    43. Re:This is not Star Trek by Christopher+Thomas · · Score: 1

      This is useful because anyone who can hear our signals and generate signals for us to hear in return is almost certainly far more advanced than we are.

      There is no proof of that. The whole hoping aliens are smarter than us is a bad assumption. If it took so long for life to evolve here, it would probably take just as long if not longer in other conditions.

      If anyone responds to us, then life has already evolved, so that issue is not relevant. The relevant question is, "given that someone is there who _can_ respond, how advanced are they likely to be compared to us". For reasons outlined in my previous message, the answer is "much more advanced", as less advanced or non-existant people wouldn't be responding in the first place.

      Your arguments instead influence the question of how likely it is that we get a response at all, but that was not under debate (different issue).

    44. Re:This is not Star Trek by Christopher+Thomas · · Score: 1

      I find it disturbing that futurists tend to presume that the benefits of communication outweigh the risks. Okay, an Independence Day scenario is not likely. But how unlikely? 1 in 10 chance? 1 in 100? 1 in 1000? 1 in 10000? What is an acceptable risk?

      We are already broadcasting more than enough radio noise to be easily seen by any hypothetical aliens who are hunting down and destroying other races, so attempting contact does not substantially increase the risk of this scenario.

      Furthermore, due to the vast resources needed to cross between the stars, a campaign of interstellar conquest is fundamentally useless. Anything you could possibly hope to gain would be much more easily obtained by devoting the same resources to producing it in your own system.

      In summary, attempting to commmunicate with aliens does not substantially increase the risk of conquest, which is for practical purposes zero in the first place.

    45. Re:This is not Star Trek by cellocgw · · Score: 1

      Yes, no argument about the limitations of Bussard. I just wanted to slide in a ref. to a pretty cool (given its publication date) sci fi yarn.
      Sorry for the misdirection.

      --
      https://app.box.com/WitthoftResume Code: https://github.com/cellocgw
    46. Re:This is not Star Trek by bc8o8 · · Score: 1

      SURE we can reach them!! All we need to do is construct an infinite improbability drive and plug in the improbability of M$ on day writing a secure, reliable operating system and we can go anywhere we want...

    47. Re:This is not Star Trek by p3d0 · · Score: 1
      Settle down. He was being ironic.

      Besides, considering the size of the galaxy, 90 light years is very, very close. I think it's clear that's all he was saying. He wasn't implying that we could drop by for a visit.

      --
      Patrick Doyle
      I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
    48. Re:This is not Star Trek by p3d0 · · Score: 1

      Have a close look at the sentence you quoted, and you'll see that the amount of time it takes for life to evolve is not relevant. Hint: only aliens with radios are under consideration.

      --
      Patrick Doyle
      I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
    49. Re:This is not Star Trek by 1u3hr · · Score: 1
      True, but it should be pointed out that for decades after that, most scientists thought it was physically impossible to break the speed of sound in an aircraft. There was no physics that allowed > Mach 1 speeds to be achieved. With time, that theory was also proven wrong.

      I doubt that. In fact I doubt it so much that I challenge you for a citation.

    50. Re:This is not Star Trek by Suppafly · · Score: 1

      Hint: only aliens with radios are under consideration.

      Having radios doesn't mean they are more advanced than us. We've had radios for a long long time.. What we are doing in regards to space exploration now could have been easily accomplished 20-30 years ago had space exploration been as big of a concern as say military weapons development.

      Look at it another way.. Had we received transmissions from aliens 50 years ago, we probably could have replied, and I'm sure you'd agree that we are somewhat more advanced now than 50 years ago.

    51. Re:This is not Star Trek by Anonymous Coward · · Score: 0

      If we can build an interstellar spacecraft, chances are good that the technology might also exist to freeze humans for the trip. I have never tested this myself, but I am sure a person in suspended animation can withstand more acceleration than a normal person could. Cryogenics also solves the problem of the crew members being massively bored during the trip, or excessively old on the arrival to the destination.

      Some sort of gravitational point source near the front of the craft may also solve the acceleration problem. If the source is variable, then it is possible for the crew to not experience any acceleration forces at all. Also when the craft turns around and fires the engine(s) to slow down, this same gravitational point source would keep the crew from having trouble during negative acceleration. Obviously, I have no idea how this magical gravitational point source might be generated, but that isn't really my point.

    52. Re:This is not Star Trek by DG · · Score: 1

      Ahhh, no.

      The issue with "breaking the sound barrier" was largely an engineering problem, not a theoretical one.

      Bullets, for example, had been supersonic for quite some time.

      The trick was learning to design an _airfoil_ that could provide sufficiant lift at speed ranges that would allow subsonic takeoff/landing but yet still allow controlled supersonic flight.

      It's all about the behaviour of air at high speeds - its material properties, if you will. But there was very little physics going on.

      This is vastly different from the FTLiaV problem, where it appears the very nature of the universe conspires against you.

      DG

      --
      Want to learn about race cars? Read my Book
    53. Re:This is not Star Trek by p3d0 · · Score: 1
      Having radios doesn't mean they are more advanced than us. We've had radios for a long long time..
      Are you seriously suggesting that a couple of centuries is a long time? Good grief man. I'm speechless.

      Anyway, my point still stands that none of this has anything to do with how long it takes for life to evolve.

      Had we received transmissions from aliens 50 years ago, we probably could have replied, and I'm sure you'd agree that we are somewhat more advanced now than 50 years ago.
      So you are concluding that there is a good chance the aliens are technologically behind us? That's a hell of a leap.

      A race with radio must be no more than a couple of centuries behind us, but could be thousands or millions of years ahead of us. Think about it.

      --
      Patrick Doyle
      I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
    54. Re:This is not Star Trek by Suppafly · · Score: 1

      A race with radio must be no more than a couple of centuries behind us, but could be thousands or millions of years ahead of us. Think about it.


      Statements like that just show an ignorance of statistics. The odds of there being aliens more advanced than us is the same as there being aliens that are less advanced than us. Not to mention that you are using human intelligence as the metric for all intelligence. It is also just as likely that a civilization would have radio technology far better than our own, but would be horribly behind in other areas.

    55. Re:This is not Star Trek by Anonymous Coward · · Score: 0

      well seeing how fast technology develops here id imagine by the time I die or hope to die that we will have significantly fast spacecraft of some sort.
      I don't want to lean too far into "science fiction" but just because science fiction portrays scary aliens coming to our planet to crap long sticks up peoples asses id have to say that there is no doubt alreadly another civilization out there with the power to travel quite far. I know this will get some stubborn resposnes like thats immpossible but yeas. maybe ti us. We don't know of anything else right? of course.im sure before the end of the next few centuries or maybe millenium there will be a better way to send people into space than blasting them off in a rocket. Look at magnetism. We know[ Reply to what it is but does anyone know Why it is or truly understand it completely . Nope

    56. Re:This is not Star Trek by p3d0 · · Score: 1
      Not to mention that you are using human intelligence as the metric for all intelligence.
      Ok, I think I see where you are coming from. I am equating how advanced a civilization is with time elapsed since the invention of radio. Granted, there are many other ways to measure "advancement".

      Do you agree that an alien race with radio is likely to have possessed it for longer than we have?

      I only wish you had expressed yourself more clearly in the first place instead of resorting to calling me ignorant.

      --
      Patrick Doyle
      I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
    57. Re:This is not Star Trek by Suppafly · · Score: 1

      Do you agree that an alien race with radio is likely to have possessed it for longer than we have?

      No, I wouldn't even agree to that..there is nothing that would lead me to believe that an alien race within communication range of earth has had radio technology longer than we have. As I said, statistically, the odds of there being aliens more advanced than us are the same as there being aliens less advanced than us in regards to radio communication and otherwise.

      It's one thing to assume there is intelligent life out there, it's another to make assumptions about it trying to use the evolution of intelligent life on earth to measure it.

      The only way I'd even consider that intelligent aliens have had radio technology longer than us is if they got in touch with us before we got in touch with them.. We've been trying to contact intelligent alien life for a long time and haven't gotten any answers.. using your assumption that aliens would be similar to us, it would stand that if aliens have had radio technology longer than us, they'd make first contact, not us.

    58. Re:This is not Star Trek by Zan+Zu+from+Eridu · · Score: 1
      Some sort of gravitational point source near the front of the craft may also solve the acceleration problem. If the source is variable, then it is possible for the crew to not experience any acceleration forces at all.

      Yeah, but if we'ld have variable gravitation, we could use that as propulsion too: build two identical spaceships with such a gravity source. Starting with the two ships orbiting eachother, when one ship goes in the direction you want to travel, make it heavier (and the other ship lighter) so the lighter ship accelerates in the right direction. Now repeat the process with the ships roles reversed, ad infinitum.

      (Also assuming we ever get this magical gravitational point source ;-)

    59. Re:This is not Star Trek by p3d0 · · Score: 1
      As I said, statistically, the odds of there being aliens more advanced than us are the same as there being aliens less advanced than us in regards to radio communication and otherwise.
      What are these "statistics" you keep referring to? There are no statistics on alien races because we haven't yet even encountered a single one. What statistics are you talking about?
      there is nothing that would lead me to believe that an alien race within communication range of earth has had radio technology longer than we have.
      You are telling me you would expect that half of all radio-possessing races discovered radio in the last 200 years, and the other half discovered it before that. Given that the universe is something like 10 billion years old, that means that the rate of radio discovery, among races that currently possess it, has been 50 million times more rapid in the last 200 years than in the previous 10 billion years.

      Do you have some explanation for this extraordinary explosion of recent activity?

      The only explanations I can think of are:

      • Coincidence. I find this highly unlikely.
      • There is some common element among all alien races that they all required the same amount of time to discover radio. I find this level of uniformity highly unlikely, given the variations among creatures even on our own planet.
      • Races that discover radio tend to destroy themselves after possessing radio for an average of less than 400 years. Obviously we have no evidence either way on this one.
      • ??
      To me, it seems overwhelmingly likely that most radio-possessing alien races would have had it longer than we have.
      --
      Patrick Doyle
      I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
    60. Re:This is not Star Trek by Suppafly · · Score: 1

      What are these "statistics" you keep referring to?

      Statistics is a branch of mathematics, if you go to college you generally get a decent introduction to statistics. As I pointed out before, your statements show an obvious ignorance of statistics.

    61. Re:This is not Star Trek by p3d0 · · Score: 1
      What are these "statistics" you keep referring to?
      Statistics is a branch of mathematics, if you go to college you generally get a decent introduction to statistics. As I pointed out before, your statements show an obvious ignorance of statistics.
      No, numbnuts, I mean what are the numbers that you're using? How did you decide that "statistically, the odds of there being aliens more advanced than us are the same as there being aliens less advanced than us"?

      You're making it very hard for me to believe you're not trolling me. I can't imagine you actually think I don't know what statistics are.

      Listen. I think your claim is that any given alien race is equally likely to be more or less advanced than we are. I agree with that statement. I'm making a different statement. Read carefully: I'm saying that any given alien race with radio technology probably has had it longer than we have. You keep referring to "statistics" which is absurd because we don't have any statistics on alien races. We haven't found one yet.

      So put up or shut up. Stop waving your hands and make your point or I'll be forced to conclude you don't have one.

      --
      Patrick Doyle
      I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
    62. Re:This is not Star Trek by schlyne · · Score: 1

      All we need is the infinite improbablity drive. Who says we need wormholes?

      --
      I love deadlines. I like the "whoosh" sound they make as they fly by. -- Douglas Adams
    63. Re:This is not Star Trek by Suppafly · · Score: 1

      Read carefully: I'm saying that any given alien race with radio technology probably has had it longer than we have.

      No sir, it is you who is trolling me.

    64. Re:This is not Star Trek by Anonymous Coward · · Score: 0

      Hardly.

      Accelerating at a constant 1g for 354.3 days would get you close to the speed of light. Flip around at the midpoint, decelerate for another 354.3 days and you arrive at your destination. That would get you to the nearest stars in what, 5 or 6 years absolute time, maybe 3 years subjective. There are thousands of stars we could reach in under 20 years subjective travel time.

      Of course there's lots of pesky issues like your acceleration per second being in subjective time, so I'm sure my math is off, but it's probably not bad.

      And we have no idea how to build a drive that can accelerate a ship at 1g for 2 years, or a ship that can survive the radiation and small debris problems of travelling close to the speed of light, but those are engineering problems, not ones that require new physics.

    65. Re:This is not Star Trek by p3d0 · · Score: 1
      No sir, it is you who is trolling me.
      On the off chance that you actually believe this, I'd just like to point out that I have made an effort to explain myself very thoroughly, while you have merely asserted repeatedly that some miraculous yet undisclosed statistics indicate that you are correct.

      I hate to make enemies, but if you refuse to discuss this in a rational manner, without glib one-sentence replies or appeals to the authority of your magic statistics, I see no alternative.

      --
      Patrick Doyle
      I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
    66. Re:This is not Star Trek by Suppafly · · Score: 1

      just let it go.. you failed to understand my point, and you've failed to make one of your own. it's over.. get on with your life.

    67. Re:This is not Star Trek by p3d0 · · Score: 1
      Do you agree that an alien race with radio is likely to have possessed it for longer than we have?
      No, I wouldn't even agree to that..there is nothing that would lead me to believe that an alien race within communication range of earth has had radio technology longer than we have.
      You keep changing the subject. I'm not talking about all alien races within communication range of earth. I'm talking about alien races with radio technology.

      Suppose I just turned 17, and I have had my driver's license for 1 month. Is it safe to say that a typical person with a driver's license has probably had it longer than I have? Answer: yes, because of all the people out there with licenses, only a small fraction obtained them in the last month. I'm not talking about all people, or all people within driving distance of my home. Only those with driver's licenses.

      Likewise, I'm not talking about all alien races, or all alien races within communication distance of earth; only aliens who already have radio. How many of them obtained it in the last 200 years, rather than in the 10 billion years before that? Unless you have reason to believe otherwise, it seems overwhelmingly likely to me that the fraction would be very small.

      --
      Patrick Doyle
      I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
    68. Re:This is not Star Trek by Anonymous Coward · · Score: 0

      Thank you, this is the explaination that he needed (and hopefully learned from. And thanks again for saving me the time to think up something to clear up this misguided soul.

      -Tim the AC Poster Child

    69. Re:This is not Star Trek by Anonymous Coward · · Score: 0

      He also keeps saying we've had radio for "a long time". He doesn't understand just how short a time we've even been here as a species, much less had radio.

      -Tim the AC Poster Child

    70. Re:This is not Star Trek by Anonymous Coward · · Score: 0

      Yup, Troll.

      In more ways than one too. It's obvious Suppafly doesn't actually understand this strange new thing called statistics he learned last semester. Maybe he can ask his professors about this example next fall.

      -Tim the AC Poster Child

    71. Re:This is not Star Trek by Anonymous Coward · · Score: 0

      No, it's not.

      In order to develop radio, a certain amount of classical Electricity and Magnetism must be known. This presupposes a certain knowledge of mathematics and other basic sciences. It would also not be a large assumption to say that their particular world has similar natural resources as ours, and thus has as much easy experimentation with metals, etc. This is due to the way planets are formed from old stars which only create certain elements, and the fact that if we're talking about inhabitants of something like a gas giant where metal might be very hard to get, they likely won't have radio and are thus out of the set of aliens we are discussing.

      In short, it's fine to assume that aliens with radio have a certain amount of other knowledge, and that they will be able to develop far beyond radio (at least as far as we will be able to).

      -Tim the AC Poster Child

    72. Re:This is not Star Trek by tompaulco · · Score: 1

      While I tend to agree that faster than light travel is impossible with currently known laws, I have to play Devil's Advocate for a moment. How do we really know there aren't things out there going faster than the speed of light? Would we even be able to see an object going faster than the speed of light?

      --
      If you are not allowed to question your government then the government has answered your question.
    73. Re:This is not Star Trek by vlad30 · · Score: 1

      thats right and when you consider there are 250,000 stars within 250 light years of earth makes our chance of other life out there even more likely

      for scale see here http://www.anzwers.org/free/universe/250lys.html

      and zoom out

      --
      Your'e all thinking it, I just said it for you
    74. Re:This is not Star Trek by barawn · · Score: 1

      That's a ramjet, not a ramscoop, which is what I'm proposing. Though it's not really a ramscoop, more just a particle collector. The benefit of space is that, well, there's virtually no drag, and so you can coast when you run out of fuel until you get enough. This means that you have a speed limit for short distances, but there are no short distances in space.

      If it's fundamentally impossible to get it to fuse in flight, then it's always possible to contain the material, store it, process it, and fuse it later, and increase your speed. Why not? It hasn't cost you anything, or if it did, very little.

      So long as you can pick up any material, your speed isn't limited at all. Drag in the ISM is pretty much nonexistent, except at high Lorentz factors. It's only 1 particle/cubic centimeter, after all, and the specific impulse that you get from every particle you pick up is orders of magnitude larger than the cost of ramming into it, so you can coast for a long time before worrying about slowing down too much between the periodic "bursts" of acceleration.

      At that point, all you need to worry about is how you power the craft continuously, but that would most likely be solved by better fusion as well - the same that provides the periodic propulsion.

      Disclaimer: I haven't actually worked out specific math on this proposal (I doubt anyone would - it's dumb, from a human point of view. It would probably take a long time to get to relativistic speeds - a very long time. But it would get there) but it was just worth pointing out that while there are of course fundamental limits to crafts that carry fuel along with them, there are always options. Nature wasn't -that- cruel to us.

      The other point regarding the cost of antiproton factories and solar collectors is naive. An antiproton factory needs (virtually) only energy (and coolants, etc., but a closed enough system can keep those losses down), and solar collectors provide that energy. After that, the quantity of antiprotons you get is just a function of how long you wait. They're luckily easier to store than positrons, so again, it's just a matter of time. So if you want an "unrealistic amount of antiprotons", you need only pay the initial cost, and wait an unrealistic amount of time. Yes, this is naive as well, assuming maintenance costs are zero. However, for this kind of a setup, I highly doubt that after several years, maintenance costs would be significant, and in addition, there are many real uses of antiprotons in medicine and other fields, and one could easily recoup the maintenance costs by selling off a small fraction of the production.

  5. Cosmic Wonders! by Anonymous Coward · · Score: 5, Funny
    Whatever they find there, it just ain't gonna compare to the cosmic goatse.cx.

    Don't worry, kids, it's a NASA site!

    1. Re:Cosmic Wonders! by Anonymous Coward · · Score: 0

      ROTFL! I wonder those who haven't seen the orginal goatse can be talked it to seeing the shape in it.

  6. we might be able to find intelligent life. by McAddress · · Score: 3, Funny
    All we have to do now is make a craft that can go 90 light years within a reasonable amount of time. minor detail.

    And one other detail, we have been mostly unsuccessful at finding intelligent life on earth, what makes us think we can find it somewhere else?

    1. Re:we might be able to find intelligent life. by Xilman · · Score: 4, Insightful
      All we have to do now is make a craft that can go 90 light years within a reasonable amount of time. minor detail.

      We already have the technology that could get us there in around a couple of thousand years --- and only 1000 if you were happy with a fly-by mission. The 1970s Daedalus study by the BIS showed us how it could be done using only technology known at that time or reasonably expected to be available by the turn of the millenium. To this extent, it is indeed a minor detail.

      There are two major details, IMO. The first is cultural: we no longer seem to want to embark on projects that are expected to have payback times measured in centuries, as the builders of the Egyptian pyramids and the European mediaeval cathedrals did. The other is economic: even if we wanted to do something like this, the cost would be enormous. OTOH, perhaps the cost might be no greater in societal terms than the price to the Egyptian economy almost 5000 years ago of building the great pyramids.

      Paul

      --
      Lasciate ogne speranza, voi ch'intrate
    2. Re:we might be able to find intelligent life. by kramer2718 · · Score: 1

      I really wish that I could mod you up for such an insightful comment, but the Slashdot gods have not awarded any lately, so I'll reply:

      Perhaps you are right that humans have become too short-sighted to embark on any projects to further our species (look at the vast majority of government policies anywhere), but I don't think that we need build such a huge space ship just yet.

      I think it will happen, but only after we have developed the technology to conquer our own galaxy. Then when we arive at the next star system, we can actually perhaps make it livable.

    3. Re:we might be able to find intelligent life. by Humpinate · · Score: 1

      But, on the third hand (Larry Niven) we also might want to contemplate the Republican side and use the metals-extraction technology and null-gravity refinment technology to make oodles of bucks, thereby stair-stepping the building of this radio/emitter to contact this other similar system.

    4. Re:we might be able to find intelligent life. by gadfium · · Score: 1

      I remember the Daedalus study, I subscribed to the Journal of the BIS at the time.

      One "problem" with the proposal was that if we sent such a probe, it might report back in 1000 years, but if we waited another century, we could send a probe that would get there in half the time, so we'd get the information in only 600 years.

      Of course, in two centuries we'd be able to send a probe that could get there more quickly still, and maybe have the data less than 500 years from now. Of course there is a limit to this converging sequence.

      The figures I've given above are just to illustrate the point. I no longer remember what the actual figures were. I seem to recall that Barnard's Star (about 6 light years away) was the nominal target at the time.

    5. Re:we might be able to find intelligent life. by Noofus · · Score: 1

      I do remember a ST:TNG episode where they found a probe sent by earth at around our current time. I think it would be foolish if we dont try at least. Because although we may be able to build a probe thats significantly faster every 100 years or so, there is also no garantee we will ever be able to surpass the fastest (at some point in time).

      So I think it would at least be important to try to send probes, even though we hope that we could soon build faster ones.

  7. "planetary system" by Anonymous Coward · · Score: 1, Informative

    Hate to be pedantic, but using the proper terms aids clarity and, of course, helps one to sound credible, so let me offer this helpful advice:

    There is only one "Solar System," and that's the system of bodies orbiting our star, Sol.

    The generic term for any other collection of planetary bodies orbiting some random other star is "planetary system." The planets therein are referred to as "extrasolar."

    Read the original press release and paper. You will see this usage reflected there.

    1. Re:"planetary system" by CheshireCatCO · · Score: 1

      Speaking as an actual planetary scientist, we often use "solar system" for planetary systems outside out ours. And we refer to their stars as "suns" rather often, too. As long as you capitalize the proper noun version and not the general term, it's pretty obvious what you mean.

      (For that matter, we talk about Jupiter's "moons" a lot. Given that there is only one "the Moon", that shouldn't be, either. But it is, so just get used to it.)

  8. It's impossible to use a stick like that. by Carthag · · Score: 1

    As the grandparent mentioned, it's a "vibration."

    See this e2node and the ones below it for a thorough debunking of the theory.

    1. Re:It's impossible to use a stick like that. by tiled_rainbows · · Score: 1

      Firstly, didn't they just measure the speed of gravity and find it to be equal to c?


      Secondly, the faster something moves, the shorter it gets, due to relativistic effects. It's really tiny, like, the Apollo rockets got something like 0.0000001 mm shorter (haven't got the figures, you get the point) at maximum velocity, but this means as you move the stick the stick gets shorter, precise shrinkige a function of the speed you move it and the length of the stick.<br>
      So, it could well be (er, someone do the math for me, please) that the stick shrinks by the same amount you move it, meaning that the corresponding movement at the other end is delayed.<br>Maybe?

    2. Re:It's impossible to use a stick like that. by HurlyBurlyMarley · · Score: 0

      Good Point. But the stick is only moving an inch or so and not very fast (my guess would be 1 m/s). I would be pushing it, so the theory of relativity imho wouldn't make the stick much shorter.

    3. Re:It's impossible to use a stick like that. by Anonymous Coward · · Score: 4, Informative

      (a) Most physicists think gravity is transmitted at light speed. Very few (and none who believe in General Relativity) think gravity is instantaneous.

      (b) (I Am A materials scientist) "Solid" matter is composed of atoms bound together by electromagnetism. When you "push" a solid object, displacement waves (essentially sound waves), travelling from atom to atom inform the material that you are pushing it. For sufficiently fast pushes and short timescales, even a block of carbon steel looks like a wobbly jelly. This is important in impact engineering, for example, and mechanical engineers and materials scientists deal with stress waves in solids all the time (plastic torsion waves are the most "fun"). Nothing is perfectly solid.

      Your "stick to europa" would have to have unphysical infinite rigidity for instantaneous transmission. In real life, assuming you could make a stick to europa (not in itself unphysical, just extremely unlikely), a wave train would travel down the stick when you displaced one end, displacing the material of the stick. This would happen at the speed of sound in the stick, which is always significantly lower than light speed (since it is determined by interatomic interactions, themselves subject to light speed) So yes, conceivably, the drum would make a sound, but the sound would come some time after you pushed the other end of the stick, since the stick would be acting like a wobbly jelly on such a scale, as all atomic matter must.

      You can even see this in action - surely you've seen the high-speed movies of bullets hitting apples, with deformation waves crisscrossing the surface? All solids behave that way, it's just the waves travel very quickly (but not nearly as fast as light...) in some solids such as hardened metals.

    4. Re:It's impossible to use a stick like that. by tiled_rainbows · · Score: 1

      But the stick is only moving an inch or so and not very fast...

      no, it's not moving very fast, but it is rather long, and the shrinkage is a fraction of the total length. Someone reading this must know enough about relativity to do the math? Please??
      I mean, reading other comments, I can get the whole speed-of-sound waveform thing, but wouldn't the relativistic-shrinking thing have some effect?

    5. Re:It's impossible to use a stick like that. by HurlyBurlyMarley · · Score: 0

      Thanks for the response. One question if you don't mind....I have seen pictures of electron microscopes showing atoms that have been moved around to spell words, like IBM, there seem to be a ton of space, is there a way to arrange the atoms so there is little or no displacement wave? (or is this the unphysical infinite rigidity you mentioned, sorry more then one question)

    6. Re:It's impossible to use a stick like that. by turgid · · Score: 2, Interesting

      There is no such thing as a perfectly rigid body. Everything else follows from this.

    7. Re:It's impossible to use a stick like that. by Anonymous Coward · · Score: 0

      No, you can't. Atoms aren't little hard spheres, they're smeared out in space themselves, and can't be infinitely close together. Even a neutron star, essentially a huge gravitationally confined atomic nucleus, would have sound waves (though they would in fact go at a significant fraction of light speed.)

    8. Re:It's impossible to use a stick like that. by tiled_rainbows · · Score: 1

      There is no such thing as a perfectly rigid body.

      huhuhuhuhuhu...
      Shut up, Butthead! I said Shut up!

    9. Re:It's impossible to use a stick like that. by turgid · · Score: 1

      Beavis, come here wile I kick your ass...

    10. Re:It's impossible to use a stick like that. by Guignol · · Score: 1

      That's not the problem it's still an information propagation through the body that happens realy.
      There is no such thing as a rigi body the way you see it (that is, all its part move together 'instantly')
      A rigid body is made of atoms tied up together by binding forces.
      you apply a force at the start of the queue to move the stick, and you accelerate (imagining the stick is a just a long chain of atoms) the first atom toward the second, etc.. it's a "pushing chain" that propagate at about the speed of light, but not faster, so i guess that would effectively define a theoretic maximum length for any 'solid body'.
      Since beyond that length, atoms aren't 'suficently' moving together (there's too much of a delay to watch the global movement as a whole thing, and all elements aren't moving together at the same speed, whi is the requirement for it to be considered solid)
      Anyway, you're out of luck with that stick.

    11. Re:It's impossible to use a stick like that. by barawn · · Score: 2, Interesting

      No. Relativistic contraction happens only in the direction of motion. The stick would "thin", not shrink.

      If you shoved it "towards" Europa, for instance, then the stick would shrink slightly, but, if you're jiggling the stick back and forth, the stick would be shrinking, expanding, shrinking, expanding as you stop and start the motion. It's even worse than that as you're attempting to move a massively elongated object, so you get displacement waves rather than motion.

      Plus the fraction that we're talking about here is REALLY small. Look it up - just look up Lorentz contraction somewhere, and use a value of, I don't know, v = 1 m/s (which is still fast). It's ungodly small - somewhere in the vicinity of 1 part in 1 billion.

      It's not an easy question to answer - there are quite a few complications involved - but it suffices to say that nothing weird happens. The stick would take a long time to move (at least the characteristic period of the object - speed of sound*length) and if you tried to shove it harder, you'd just distort the stick (bend/break, etc.) and send a wave down the stick, thus moving YOUR end, but not moving the entire object!

      I mean, let's work it out - let's assume that it's a billion meters long, so moving it at 1 m/s shrinks it by 1 meter. Let's also say that the speed of sound in the material is 1000 m/s, so it takes a million seconds for a "push" from one end to move to the other end. In order for you to actually see any real Lorentz contraction (from the whole stick), the entire thing has to be moving at 1 m/s, not just the end - Lorentz contraction comes from the fact that a reference frame moving with the stick must measure the speed of light the same as you do, and the 'fractional' contraction is due to the fact that the frame at the very far end of the stick is the same frame as the initial end of the stick.

      So, in order for you to see the billion-meter long stick shrink by 1 meter, you'd have to wait a million seconds. And by then your end would have moved one million meters, and if you measured the length of the stick while it was moving at 1 m/s, you'd get 999,999,999 meters. It wouldn't be a sudden jump - it'd smoothly decrease in size as more and more of the stick begins moving. Then, when you try to stop it, it'd take a million seconds for the stick to stop, and the stick would smoothly stretch back out to 1 billion meters.

      But, in the end, it still would've moved a million meters. It's only during the motion that you see anything weird happen.

      So if you grab it before the whole thing starts moving, then the total contraction would only be due to however much of the stick is actually in motion.

    12. Re:It's impossible to use a stick like that. by grub · · Score: 1


      There is no such thing as a perfectly rigid body.

      Uhh.. what do think is responsible for the goatse.cx guy's condition?

      --
      Trolling is a art,
    13. Re:It's impossible to use a stick like that. by turgid · · Score: 1

      Photoshop? The GIMP?

  9. Proof the Earth has 40 years to live by tjstork · · Score: 1

    The aliens on this planet will receive the first television signals from Leave It To Beaver. They will immediately drive their FTL space battleships to earth and blow it up.

    --
    This is my sig.
  10. Prior art Re:patent by edgrale · · Score: 1

    Our solar system is only 9 billion/mrd years old? So they have prior art!

    Damnit!

    --
    09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
  11. Old radio waves from the earth by hankwang · · Score: 1
    >We've already been sending out artificial radio waves from Earth for around 100 years.

    Most of those radio waves are drowned in noise, alone by the fact that there are too many transmitters that share the same frequencies. All those powerful broadcasts for radio and TV are radiated into outer space, but from a long distance one would see a superposition of all those signals for different TV and radio stations, i.e. noise.

    The exception is the short-wave radio band. Because one can receive a powerful SW station over the whole world, the frequencies in that band do not overlap. Unfortunately, the ionosphere that reflects the SW broadcasts will also prevent aliens to receive them.

    1. Re:Old radio waves from the earth by turgid · · Score: 1

      I see what you mean. However, wouldn't the amount of noise in these bands be much higher than you would expect to occur naturally? If you took a spectrum of radiation coming from the vicinity of earth (assuming it wasn't right in front of the sun) wouldn't they be disproportionately strong?

    2. Re:Old radio waves from the earth by tiled_rainbows · · Score: 2, Insightful

      "...but from a long distance one would see a superposition of all those signals for different TV and radio stations, i.e. noise."


      Ummm, has someone told those SETI guys this? Maybe that's why we haven't found anything yet...

    3. Re:Old radio waves from the earth by hankwang · · Score: 1
      >However, wouldn't the amount of noise in these bands be much higher than you would expect to occur naturally?

      Let's try to estimate that. Consider the frequency range around 1 MHz, the MW AM broadcast band which has been in use for quite some time. The range is something like 0.7--1.5 MHz, or 200--400 m wavelength. I'm not so sure about the total power installed in the world; say 500 kW for every 200x200 km area of populated land. That is maybe 200 MW of total installed power (that feels like a high estimate).

      How much does the sun radiate in the 200-400 m wavelength region? The Planck black-body equation says that the sun (temperature 5700 K) radiates 1e-17 W/m2 in this wavelength range. Multiplied by the surface (5e18 m2) of the sun: 50 W.

      So, yes, our Earthian broadcasts will easily overpower the noise caused by the sun in the MW radio range. The alien astronomists will be very confused about the radiation emanating from that star with an intensity that is periodic in 24 hours and construct theories about ionized particles that emit radiation in mentioned band while interacting with the star's magnetic field. :)

      Disclaimer: I don't know enough about astronomy to know what sources other than blackbody radiation exist in the MW frequency range.

    4. Re:Old radio waves from the earth by hankwang · · Score: 2, Informative
      > Ummm, has someone told those SETI guys this? Maybe that's why we haven't found anything yet...

      I think they're hoping to detect a transmission that is meant to be detected, in the range 1.4--1.7 GHz. In that range, the thermal background of the sun is about 1e10 watt, so only a very directional narrow-band transmission has a chance to be noticed.

      I remember that people have tried to send a message to a few nearby stars a few years ago with a powerful directional transmitter. The message was a series of pictures, explaining how we look like, how we count, what our solar system looks like, etc. I can't remember what it was called, but that's the kind of transmission that we might receive.

    5. Re:Old radio waves from the earth by hankwang · · Score: 1

      I found it: it is the Cosmic Call project, it has been discussed here before.

    6. Re:Old radio waves from the earth by Anonymous Coward · · Score: 0

      A PDF of the full message can be found on the CETI page.

  12. The universe does not care what we dream. by Christopher+Thomas · · Score: 2, Insightful

    The same applies to space flight now. We can dream it, but we can't figure out how to do it. Some day, a bunch of different people will come up with a bunch of theories on "super-luminal" travel, then set out to prove their theories. One of them will be proven.

    Why are you certain that one of them will be proven?

    The universe is what it is, regardless of what we _want_ it to be. This may or may not include mechanisms for FTL travel, but we have seen no evidence of such phenomena occurring to date, and our models of the universe are self-consistent without them.

    In the absence of observerations of FTL effects and of a theoretical mechanism by which it would occur, the most reasonable assumption is that it _doesn't_ occur.

    If our universe is truly bound by the speed of light, wishing for FTL drives won't change a thing.

    The wise thing to do is plan for STL, and continue learning all we can about the universe in the hopes that a loophole eventually shows up.

    [ObPedant: Yes, I know about the various types of "space warp" drive proposed; however, these rely on negative energy density, which causes serious problems (does not appear to be consistent with our models of the universe). A few groups have been trying to demonstrate that negative energy density is possible. If they succeed, great, but until then the null assumption holds.]

    1. Re:The universe does not care what we dream. by Anonymous Coward · · Score: 0

      A study was recently done where the speed of light was actually reduced. I am not sure the degree to which this was done, but the mear fact that this can be accomplished is something to raise at least an eyebrow over. Many quantum formulas are based on the "constant" c, and these formulas are what many point to when they say that FLT is impossible and we should forget about interstellar travel. But is the speed of light really a constant at all?

      If an environment is created around the spacecraft where the laws of physics are warped according to our new value for the speed of light, then what effects might this have on how fast you can really go? With a backpack full of warped laws of physics, it might be possible to leap those 90 light years in a single bound and forgo the spaceship altogether.

      There are many discoveries yet to be made (unifying theory to name just one) to be able to say with certainty that FLT is "impossible".

    2. Re:The universe does not care what we dream. by Christopher+Thomas · · Score: 2, Informative

      A study was recently done where the speed of light was actually reduced. I am not sure the degree to which this was done, but the mear fact that this can be accomplished is something to raise at least an eyebrow over.

      The propagation speed of light in a medium has been reduced in the lab - not the speed of light in vacuum, which is the important number.

      There are hints that the speed of light has varied slowly over the age of the universe, but this doesn't help us build space drives.

  13. holy crap by AssFace · · Score: 2, Funny

    After reading that, I can definitely walk away with one thing firm in my mind:

    You must get laid incredibly often with that schpiel

    --

    There are some odd things afoot now, in the Villa Straylight.
  14. More info from New Scientist and others by securitas · · Score: 2, Informative


    A bit more info from a previously submitted post:

    New Jupiter-like Planet Discovered in Sol-like system

    A new Jupiter-like planet has been discovered in a circular orbit around a Sun-like star 90 light-years away in the constellation Pupis. What is remarkable about the discovery is that this system is the most like our own solar system discovered to-date. This development lends credence to the theory that systems with small, rocky Earth-like planets are out there. ''This is the closest we have yet got to a real Solar System-like planet and advances our search for systems that are even more like our own,'' said UK team leader Hugh Jones of Liverpool John Moores University. Jones went on to say that, ''Jupiter's position is probably crucial to the distribution of other planets in the Solar System.'' Current thinking on planet-formation indicates a large, Jupiter-like planet in a circular orbit would allow the relatively undisturbed formation of an inner system of smaller Earth-like planets. The newly discovered planet is about twice the mass of Jupiter with an orbit equivalent to the asteroid belt in our own solar system.

    1. Re:More info from New Scientist and others by Anonymous Coward · · Score: 0

      I appreciate your efforts, but the Wired News article covered this and more.

  15. Pesky physics. by SHEENmaster · · Score: 1

    I miss the days of logical phyysics, where you could theoretically keep accelerating that entire distance and arrive in less than 90 years.

    Anyways, who are we kidding? We are looking for planets like Earth not for life, which will evolve to suit nearly any environment, but to find possible colonization sites.

    For that, a smelloscope would be much more useful.

    --
    You can't judge a book by the way it wears its hair.
  16. Giant ice cubes as space ships by gerald626 · · Score: 1
    I read a book a few years ago, called SIVA or SHIVA (don't quite remember). Anyway, this book was about how our own ancient civilizations (egyptian I believe) had created giant space ships out of ice. People inside the giant ice cube could use the ice as water, and the sheer mass of the thing would act as a collector for hydrogen atoms - isn't the universe made up of mostly hydrogen (or was that helium? ;)


    The velocity was increased gradually by using the hydrogen as fuel. Of course, the book said that 3 of these ships were created, and 2 had returned, but that the last one had gone missing, of course. And that the pyramids were basically beacons or antenae, and that there were more pyramids on under one of the poles.


    but the point is, if you had a giant hydrogen collector on the front of your ship, you could use that as additional fuel. And you would presumably only be able to accelerate half way, then reverse the process and decelrate the second half of the way, since it would take you just as long to slow down as it would to speed up. So your max speed might be close to 1LY, but not necessarily for very long, depending on the distance travelled.


    Just a thought - and if anyone has a copy of that book, I'd love to get my hands on it!


    Gerald

  17. How much like ours? by Anonymous Coward · · Score: 0

    How much alike is the other solar system? Does it have a planet Earth, too?! One in which Lincoln and JFK were never assasinated, and Elvis lived to be an old d00d?! And Adolf Hitler became an artist and World War II never happened?! And the Justice League of America fights the bad guys and always wins?!

  18. I hate to rain on your parade... by chainsaw1 · · Score: 1

    No, it won't work that way.

    In the 1600's, it was possible to make things go through the air. You can throw a rock through the air. Birds can fly outright. It, therefore, was somehow possible to do.

    Supersonic flight was believed impossible, but mostly as an engineering challange (resisting massive pressures, etc.) not scientific law.

    Superluminal speed is impossible from scientific law. We have never, EVER seen anything or made anything go faster than light. We may be able to get things moving AT the speed of light or close to it, but I doubt beyond.

    The only thing we have "seen" which may account for this [that I can think of] is the (currently unknown) path of an electron around a nucleas. But for all we know that may be 4+ dimensional travel, or travel outside our space-time.

    --
    - Sig