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Space Science

Solar Sails 133

Posted by michael
from the beating-swords-into-plowshares dept.
carpediem55 writes "Reuters is reporting that The Planetary Society (founded by Carl Sagan) is bringing science fiction to life, with a Solar Sail powered by light." But get how they plan to launch it: on a Russian submarine ICBM. The sponsors have a site with more information.
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Solar Sails

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  • by Anonymous Coward
    Incidentally, since nobody bothered to mention it - the name of the Solar Sail mission is "Cosmos 1". It's being sponsored by Cosmos Studios, a commercial venture started by Carl Sagan's wife, Ann Druyan. "Cosmos", of course, was the famous PBS series by Carl Sagan - who started the Planeary Society in the first place. So this mission is being undertaken in a sense in memory of Mr. Sagan. Given that NASA wasn't planning to launch a solar sail test for nearly a decade [slashdot.org], this seems like a real coup. It's an ambitious plan, and if they pull it off, the Planetary Society really deserves kudos for doing so.
  • Many apologies to Lennon, McCartney, and well, Lennin

    In the town where I was born
    Lived a man who sailed to sea
    And he told us of his life
    In the land of submarines
    So we sailed up to the sun
    Till we detonated the torpedo of green
    And we crashed to the floor
    In our Russian submarine

    We're All dying in our Russian submarine,
    Russian submarine, Russian submarine
    We're All dying in our Russian submarine,
    Russian submarine, Russian submarine

    And our friends are all on board
    Many more dead on the floor
    And the water begins to flow!

    We're All dying in our Russian submarine,
    Russian submarine, Russian submarine
    We're All dying in our Russian submarine,
    Russian submarine, Russian submarine

    As we gasp and try to breathe
    Everyone of us has all we need
    Bottle of Stoli, and a pair of jeans
    In our Russian submarine.

    We're All dying in our Russian submarine,
    Russian submarine, Russian submarine
    We're All dying in our Russian submarine,
    Russian submarine, Russian submarine

    We're All dying in our Russian submarine,
    Russian submarine, Russian submarine
    We're All dying in our Russian submarine,
    Russian submarine, Russian submarine

  • Why is that particular point made? Because its Russian, or because it's an ICBM?

    Might be because it's being launched from a submarine? Apart from SeaLaunch [sea-launch.com], how common are satellite launches from sea? I don't know, but I would assume they're not that common (and particularly from a submarine).

    -dair
  • The solar sale does *not* use the solar wind (the ejected ions and other debris from the sun) but rather the momemtum of individual photons of light.

    Yep, sorry - the momentum does indeed come from photons.

    However, the intensity of light falls off as 1/r^2 from the source, so you wouldn't accelerate too much before you were left floating in space.

    I suppose the attraction is that as we're (relatively) close to the sun, it's a nice way to get a boost out of the inner solar system to send a probe to the outer planets. And potentially you could use an artificial source to finish the trip - once your acceleration tails off, keep pushing it with an orbital laser (or just leave it coasting along and accept it'll take longer to get there).

    -dair
  • After hearing the semi-recent news [cnn.com] of Russians performing long-range test of their old ICBMs, it's good to hear of people finding another use of them rather than blowing up the White House.
  • Here [nbci.com] is an article from 1998.

  • > spacecraft will be operated from the Babakin
    > Space Center near Moscow.

    This is the first time I have heard of "Babakin Space Center"...
  • Does this remind anyone else of Tom Swift and the Cosmic Astronauts?

    http://www.geocities.com/Area51/Vault/3712/cosmi c. html

    This book was printed in 1960! I love how science always seems to find ways of catching up with science fiction!
  • you can always travel a shorter distance by opening up a wormhole. You mightkill your father before you were conceived, but if you want to go faster than light, you'll have to accept the consequences.

    Also, I wonder if anyone with a better understanding of these things could talk about the implications/restrictions implied by a multi-dimensional view of the universe. Like 1) is the theory of relativity a statement of life in 3-space, or does it hold if we can decide to move in time as well? 2) String theory claims that there are 11 odd smaller dimensions. is it theoretically possible to translate a position vector to these dimensions, do a song and a dance, and arrive at your destination in a jiffy?

  • Wow! Sounds great! Send me the nuclear power source and I'll start working on it right away!

    Later,
    ErikZ
  • What, 17?

    Nick at Night is your friend.

    Nenoo nenoo!
  • So Russia's saying, "Um, we're gonna go into American waters and launch an ICBM from a nuclear submarine. But, um, it's not an ICBM, it's a spaceship. Yeah. And, um, it's not a MIRV, its a, uhhhh, it's a giant space sailboat! Yeah! That's the idea! And we're gonna have to launch a dozen of them, in case one of them doesn't work. Yeah. And, um, we're gonna launch 'em ahhhhh, all at once, to ummmmm save time! Yeah! And the idea came from ahhh, Lionel Richie! No, wait, it came from Carl Sagan! That's the ticket!"

    --
  • Sailing was the most environmentally healthy way mankind ever developed to traverse large distances, and it seems appropriate that the same techniques be adapted to space travel. I am disturbed when I hear reports of engineers speculating on the construction of atomic weapon powered space craft, or such. We have already despoiled our own planet so utterly; we should keep space in its pristine purity.

    I know the original post was most likely a troll but ... ARE YOU KIDDING? Newsflash, the pristine space environment is a freaking vacuum that would kill puppies and kitties without human intervention. If we heretofore power every spacecraft sent up by all the nukes we got, we still wouldn't pump out anywhere near the radiation levels pumped out by the sun. You want to save the space environment, BAN STARS! Yeah, and if wasn't for that damn gravity, all that dust and crap wouldn't make planets on which evil sentient life forms would develop (pop into existence, your choice) who would then bring their evil polluting ways into space. YEAH, DAMN, BAN GRAVITY!

    If your concerned about the "environment", be worried about the fact that the polluting effects of putting things into space come from: launch emissions; and getting rid of the payload once its useful life expires. If you really want to save the environment, talk about less polluting launch methods and about holding companies and governments liable for filling the gravity well with shrapnel.

  • Ummm...

    "Oops, you have pushed my critique-of-western-thought button! What is it with 'conquering' everything? We have to 'conquer'the New World. We have to 'conquer' nature. We have to 'conquer' space."
    Ok, so Western thought involves a rampant urge to make order from disorder by taking an active role in discovery and learning, this is what you mean right?

    But then...

    It's unfortunate that the west is so fatalistic.
    fatalism:
    1.The doctrine that all events are predetermined by fate and are therefore unalterable.
    2.Acceptance of the belief that all events are predetermined and inevitable.

    Yep, that sounds like Western civilization alright, content to sit back and let things take care of themselves. Or wait, isn't that in direct conflict with your earlier observation?

    I guess what I'm really asking is what do you have against Western thought?

    -----

  • But I'm sure I can always be assured of some knee jerks in the Slashdot crowd

    Thanks...

    To each his own I guess, I was only trying to understand your cultural elitism [dictionary.com] sorry to have rocked your tolerant Eastern boat.

    -----

  • Um, so how do you get started in the right direction if the solar wind is blowing in the wrong direction?

    My guesses are that you use gravity to slingshot you in the right direction - perhaps I want to go to Mercury which is towards the sun, I first have to sail towards Jupiter, slingshot around it and use the built up speed to drift to Mercury. Sound plausible? Maybe not for humans because it would take too many years, but possible for robots perhaps.
  • A solar sail powered spacecraft can't tack against the 'wind'

    Sure you can. Set your sail at 45 degrees to the sun, and sunlight hits your sail and reflects off. You get thrust once as the photon hits you, and once more as the photon leaves. Setting your sail at x degrees to the sun gets you thrust at x degrees to the sun. Of course, the steeper your angle, the less sunlight you're intercepting, so the less thrust you get overall. At 90 degrees, edge-on to the sun, you get zero thrust.

    It's true , however, that you can't tack in the solar wind. That's the stream of protons blowing off the sun, and those little beasties don't bounce off your sail -- they stick.

    You can gain maneuverability by using a launching laser instead of (or as well as) sunlight. You can even use a launching laser at you home star to decelerate at your target star: cut part of your sail loose, and it will blow ahead of you, pushed by launching laser light. Put yourself in the reflected beam from the cut-away portion of sail, and voila, you have light hitting your sail from the opposite direction of your launching laser! (This idea isn't original with me of course; I got it from an essay by Niven or Brin or some such clever person.)

  • But get how they plan to launch it: on a Russian submarine ICBM

    Seems a damn sensible use of surplus (? ;-) ) submarines to me. Kind of a DIY version of SeaLaunch [sea-launch.com]. You could sail a whole fleet of these to the equator to get that optimal launch postion benefit. Surely a cheap way for emerging space nations to get their packages orbital.

    (my rant) Seems like a far better use of submarines to me than giving them to the military... mind you reckon that's precisely the reason the big boys will be paranoid about this idea being talked about by the emerging nations...(end rant) :-)

  • No, I believe all he said was that matter/information could not travel through NORMAL space at faster than the speed of light.

    It says nothing about worm holds/warp drive/hyperspace.

  • Your age is showing. ;-)
  • Ummm.....wouldn't NORAD [af.mil] be a little nervous about this?
  • The solar sale does *not* use the solar wind (the ejected ions and other debris from the sun) but rather the momemtum of individual photons of light.

    However, the intensity of light falls off as 1/r^2 from the source, so you wouldn't accelerate too much before you were left floating in space.

  • Actually, Ariane launches from French Guiana in South America, not Central America. Cheers!

    --
    dman123 forever!
  • #3) An ICBM is not designed to loft a large-size payload. A set of MIRVs, while very heavy, is relatively compact.

    #4) More to the point, an ICBM is not designed to deliver a payload to space. It is designed to deliver a payload to earth. Why do you think that Alan Shepard's flight lasted only 15 minutes? Because he was sitting on top of a Redstone ICBM.


    First of all, the Redstone rocket, used in the first two Mercury missions was not an ICBM, prior to its use by NASA, the Redstone was referred to as the "tactical Redstone," meaning that it was a tactical (deployed on, or close to, the battlefield) rather than a strategic ICBM.

    However, both the Atlas rocket, used by John Glenn's and later Mercury flights, and the Titan II rocket used for the Gemini missions were originally designed as ICBMs. The Titan II's on-board computer even included the trajectory necessary to launch a Gemini capsule into space as one of its standard pre-programmed trajectories. To say that "ICBMs are not designed to deliver payloads to orbit" is grossly inaccurate.

  • Allow me to give you a few pointers.

    First of all, you don't need to tack with a solar sail. Once you reach the half-way point you are travelling at an insanely high speed, and you will need to begin the breaking or you'll fly past your target. Thus you turn the craft around and allow the other star to begin to slowly lower your speed by pushing against your sails. A good analogy is "air braking".

    Secondly, space is currently THE most hostile environment known to man. It is alternatively extremely hot or extremely cold, and charged with lethal particles from stars and other bodies. We're not even sure we can keep people alive inside space ships for long periods of time without extensive lead shielding. I seriously doubt exploding nuclear bombs in deep space is going to compromise anything.

    -17028
  • I guess what I'm really asking is what do you have against Western thought?

    Good question, and I have another: What, pray tell, is this "west" you speak of? Where does it begin? Where does it end? What are its distinct and unique characteristics? How may we identify its citizens?

    [irony]
    "How like the east to broadly overgeneralize."
    [/irony]

  • For only 1 more million they can have the spacecraft shaped as a penguin with huge wings (disproportional to the penguins body) and call it the space penguin.
  • Carbon is ever present in plants and animals. Sugars such as fructose, lactose, sucrose et cetera, and other substances in the body contain a measure of Carbon. Would it be possible, then, to produce Carbon structures by organic means? Could we grow a segment of Carbon mesh that is large enough to be versatile or generous enough as to be bound together with other pieces? Perhaps biological spaceships might exist some day, utilizing an organic Carbon structure for a solar sail. It would require great expertise, as most complex life can not survive the vacuum of space, but it might be possible. In a micro-gravitic environment, size would be of little worry. Even if a complex organism was unable to be created, perhaps gigantic measures of carbon sail could be produced by bacteria or viri.
  • I intended to suggest that we must first find an organic means of producing pure Carbon in addition to resolving other problems.
  • The wind from the sun.

    A great story on the topic. It appears in a collection of his, The Sentinel.
  • Actually, there's a simpler way to do this. What people always forget in these sailing analogies is that space (at least our solar system) is a rotating system. So if you want to go inward, simply turn your sail 45 degrees to the sun to oppose your orbital velocity. Voila -- you fall deeper into the gravity well.

    However, for moving outward from the Earth, it may be more efficient to make use of the solar wind than radiation pressure. Tacking against the solar wind it trickier, though.
  • NO! Never!

    I would never be first in that line. After all, the rule says, never buy version 1.0! All those poor suckers are going to GPF into oblivion! Wait for 1.2 at least. :)

  • Space is hardly pristinely pure - it is full of extremely energetic radiation. Outside the Van Allen belts, the contribution of an Orion spacecraft would hardly be noticed. Inside is a different story; it could get really nasty down here if Orions lifted off the surface.

    "God bless Saint Liebowitz!"
  • Some of the wierd effects of sub-sub-atomic particles are that they just *are* here and then the next 'moment' (however you want to define time, but just as long as they aren't at different points at the same time) they *are* someplace else with no real path between the two points.

    It might seem that there is infinite velocity, but because they didn't actually have a path between the points, there isn't a velocity at all.

    --
  • Even then you wouldn't have a velocity faster than light, you'd just go from one point to the next with no apparent (from a spectators point of vew) path between them. From your point of view you would have traveled a much shorter distance at a normal velocity than conventional means would have allowed.

    --
  • Not to mention the fact that Lois Lane was played by Margo Kidder in the movies!

  • It's mostly because the Russian government will do it from a sub for dirt cheap. They need the cash and have not use for the ICBM. :)
  • blow up a baloon,

    observe how it gets thinner as it expands

    compare it to a pokey stick.. still the same thickness as you push it...

  • try tacking without a daggerboard or keel to stop the boat moving sideways with the wind over the beam...

    you can still point to windward, but you won't go there,

    to do it seriously try it in a scow where the hull doesn't perform and keel-like function

    you won't get very far.

  • They are probaly using a submarine because you can move the submarine to an equatorial area to launch the missile.

    This reduces the amount of power needed by the rocket, since the higher rotational speed of the earth at the equator gives the rocket a boost.
  • Correct me if I am wrong, but it was my understanding that a solar sail had to be a little bigger in order to carry a decent payload. Or is this just a proof-of-concept sort of thing? If they can make this sail material in bulk it could have thousands of appplications. It would be nice to be able to send out a probe to Jupiter using only a low-cost sail. This would free up more money and resources for building the actual probe, you don't have to design around large fuel tanks. This material also seems good for laser propulsion, which could get us around the solar system an beyond pretty quickly. Perhaps with the new technologies and discoveries(like the meteorite that show good evidence of previous life on Mars) the world will get its butt in gear and put some serious effort toward space exploration.


    Enigma
  • Nope. You use whatever means you find convenient to escape Earth orbit, so you're in solar orbit at the same distance as the Earth. Then use the solar sail to reduce your orbital velocity. All you need to do is position the sail at an angle to your orbit, so the resulting force is antiparallel to your orbital velocity. Your velocity decreases, and gravity does the rest.
  • Well, if you shake the can a hell of a lot, then point it where you don't want to go, then open it...

    I guess it's not a solar sail, but it would give you some propulsion.

  • by jmu1 (183541)
    I'm just waiting for the sky to be littered with Skyhooks... private residences and hotels that constently orbit the planet, powered by the same technology as this "solar sailboat". From the StarWars Universe, of course. I am glad to hear that the private sector is finaly getting into action, NASA has had little success although I am very excited about ISS.
  • Check out the Space Studies Institute [ssi.org] .

    Not yet suitable for anything more fragile than rock/ore/steel.

  • I'm reminded of The Mote in God's Eye and the poor little Moties trying to escape their planet on a solar sail powered craft.

    Poor little Moties, heh. Now there would be a culture that the word "fatalism" properly describes... and a planet that better exemplifies "despoiled".

    Not only did they use a solar sail, but they also powered it for a number of years with a massive laser (so powerful that humans living in the destination solar system saw the Moties' star change color while the laser was on). A character later commented that this was like being able to leave your engines at home. A neat trick if it worked, eh.

    I guess the next step up in travel is leaving yourself at home, e.g. Genesis Quest: Giant lasers not enough for you? How about modulating a star..

  • We have already despoiled our own planet so utterly; we should keep space in its pristine purity.

    You do realize space is awash with radiation from various sources right?
  • by BDew (202321)
    the laser would not lose intensity (1/r^2) like the Sun's radiation does. As long as the beam is not blocked/refracted/etc by "stuff" in between, the laser should work essentially forever.

  • ... Robert Forwards innovative designs coming to reality. Now all we need to do is build his solar powered lasers to provide acceleration and decceleration and send one the sails to Europa or Titan. If you have no clue to how much of Robert Forward's ideas can change the world, read any of his books (considered HARD science-fact/fiction). All of his concepts are based in true physics and theory.
  • So, is there any group that's seriously working on magnetic mass-drivers for the surface-to-space segment of things?
  • Dang, now I'm going to have that theme running through my head all day.
  • Hope they remember to disarm it first.

    Asikaa
  • You need a more maneuvourable (sp?), or faster reacting, engine for that when it comes to landing...

    What, you've never heard of tacking?

  • "Oh we are very sorry Mister President, how are we to know it was targeted at a major city instead of up....yes the fallout will be a problem. Again humblest apologies...sucker"

  • They are launching from the Barents Sea which is much further north than Baikonur.

  • I wouldn't be so quick to upload myself. Early adopters usually get it in the shorts.

    Besides, Einstein did not prove that travel faster than light was impossible. He merely proved that travel *at* the speed of light was impossible.

  • The article points out that the Russian ICBM launch is a "sub-orbital deployemt" test.

    In other words, it's not staying up there. A orbital test that will last for days, weeks, or months is scheduled for later in the year.

  • I didn't follow your link, so I might be wrong, but this technology is limited to planetary travel.

    Solar-sails (and maser sails) are very exciting because they are true interstellar drives, powered by photons that can be generated in stars or by lasers and masers.

  • Hmm... I did read the article now and it looks like I'm wrong. However, I'm not sure how this thing can accelerate past the heliopause.

    Maybe it doesn't.

    Maybe it just dumps the "drive" at that point and coasts.

  • by morie (227571)
    Launching scientific equipment from a russian sub in a ICBM:

    We ar going zhou launch zhee experiment. Da, push zhee red button, Vladimir. No! Njet zhat red button!

  • I think this is a common misconception. You can't actually go back in time to where you are now. You are at the center of an imaginary sphere. A second starts, and 'that second' propagates outward at the speed of light. If you start at 12:00 (for example), and you travel faster than light in a direction, and if the universe determines time from your watch, pretty soon you will be someplace where the time is 11:59. If you turn around and wait a minute you may see yourself leave (as the light from that event catches up to you). But if you reverse your course at faster than light, you would still arrive after you left the first time. Remember, time is relative. It's not that you're going back in time, it's that you are outracing time, or at least outracing _a_ time.

    MM

  • This propulsion technology is obviously not intended to be the sole means to move a vehicle from one location to another. But it is very efficient in long-distance travel.

    Just because you have a solar sail to propel you from location A to location B, doesn't mean you cannot also have some sort of fuel based thruster device to maneuver your vehicle at the local space-station dock or whatever.
  • While that's all well and good, I couldn't care less if a pseudo-me sees the wonders of the universe. I will still be stuck on this little ball with nothing to do but pust on Slashdot.

    Seriously, I have the same ideological problem with the transporters on Star Trek. I cease to exist while my doppleganger continues to live my life, play with my kids, etc. I mean, I have nothing against potential digital clones of myself- I'm sure we'd get along well- but I would receive no benefit whatsoever from the donation of my neural patterns.

  • > Although facinating to consider, it seems that a solar sail would be of limited use for a two way trip. A solar sail powered spacecraft can't tack against the 'wind' like a sail boat on the ocean is able to do.

    Actually it can, sort of, since the sun's gravity acts in the opposite direction to the solar wind and your ship is going to be in orbit about the sun, by angling the sails appropriately you can move to a closer orbit, as well as a more distant one.
    http://www.ugcs.caltech.edu/~diedrich/solarsails /i ntro/tacking.html

    If you are using an interstellar solar sails, possibly read "destination star" for "sun" at the far end - alternatively see
    http://www.forwardunlimited.com/pdf/tp069.pdf "Roundtrip Interstellar Travel using Laser Pushed Lightsails" (yes, you can use an Earth based laser for the return journey, and you don't have to tack into it).
    --
  • Well I'm not terribly into astronomy, so I don't follow sattelite launches much. I have no idea why launching from a submarine would be desirable, so yes, I find it curious. Maybe because there simply are more ICBMs that are available to the public in subs than on land (if any), but everything else being equal, it seems to me, that costs should be lower on land than from a submarine.

  • The first U. S. satellite was launched from a converted ICBM -- the Redstone booster.
  • Just a nitpick, but the Planetary Society was not just founded by Carl Sagan, it was founded by Carl Sagan, Bruce Murray, and Louis Friedman in 1980. Info here. [planetary.org]

    People always forget about those other two guys... kinda like Apollo 11. Everyone remembers Neil Armstrong, some people remember Buzz Aldrin (probably because he has a cool name), but who remembers Michael Collins?

  • "Ok, so Western thought involves a rampant urge to make order from disorder by taking an active role in discovery and learning, this is what you mean right?"

    Your reply illuminates the presumption that anything unconquered is by definition "disorder". This is exactly what I'm talking about. "Discovery and learning" does not necessarily equal conquering and vice versa.
    western

    2 capitalized : of, relating to, or characteristic of a region conventionally designated West: as a : steeped in or stemming from the Greco-Roman traditions b : of or relating to the noncommunist countries of Europe and America c : of or relating to the American West
    Generally the mindest of "Western civilization".

    "fatalism:
    1.The doctrine that all events are predetermined by fate and are therefore unalterable.
    2.Acceptance of the belief that all events are predetermined and inevitable."

    Yup, things sort of suck when one's whole world-view revolves around the belief that humanity is an imperfect creation, that nothing really worthwhile in this world can be done, except to work hard and resignedly hope for a better afterlife. A subconscious drive for some abstract concept of "progress", coupled with an ultimate resignation, I think leads us to strive very hard without purpose, exploiting for immediate gain. What shall we "conquer" after space?

    "I guess what I'm really asking is what do you have against Western thought?"

    Besides the dogged persistence to always want to conquer some new thing for the holy grail of some undefined "progress", nothing really. But I'm sure I can always be assured of some knee jerks in the Slashdot crowd. (Sober introspection about our mad rush to develop and conquer? What you say?!)
  • well, slow accellerating might be more the ticket. Keep in mind that it is perfectly feasable to concentrate and redirect the sunlight, and also to capture the reflected photons for use as energy (perhaps to power a hydrogen scoop and thruster)?

    For better interplanetary missions, I read the really enjoyable Web between Worlds by Sheffield. He toys with the idea of space rotors (I think Forward wrote about these as well) which basically store ALOT of angular momentum. You jump on in the middle and lower your way out on a rotor. By the time you're at the end, you're up to speed and just let go when you are pointing in the right direction.

    Both Velocity and acceleration at the tip are linear in radius, but Acceleration is quadratic in rotation while Velocity is linear, so by doubling arm length and reducing rotation speed by sqrt(2), you maintain a constant acceleration, but increase outgoing velocity by sqrt(2). Tensile requirements go up linerally by radius (it's longer, but acceleration is constant) so the material requirements are not too stringent.

    The one caveat is that you have to catch as much as you throw or else inject energy into the rotor some other way.
  • Can you think of anything better for them to do with all of they money they have? I imagine most of them have been down the 'feed the hungry' path before, probably done the 'cure a major disease' thing too, so why not 'spread humanity to the stars' as this months charity event?

    Kintanon
  • In case of slashdotting, please click HERE [reuters.com].

    Very cool story -- even though I won't move solar sails from my "Vaporware" until I actually see one in outer space...
  • Well, since we have no far distant colonies or outposts in space to warrant such a slow moving transport type ship, why should we be concentrating on this technology.
    You misunderstand several things:
    1. Our current probes are already slow. They are limited by the kick that chemical-fuel boosters can give them, and then have to coast or run complicated gravity-assist trajectories to get to their targets (does VEEGA mean anything to you?). Solar sails can be much faster.
    2. We can use solar sails on the missions we are doing now, to get more science out of them. Consider the NEAR mission. This mission is at an end because the NEAR craft is out of fuel. If it had only required fuel for small but rapid changes in velocity and instead relied on a solar sail for cruising thrust, it would be on its way to another rock. And then another, and another.
    3. Because solar sails can produce thrust without expending any mass on a more or less indefinite basis, they are one of the big enabling technologies for real exploration and colonization of the solar system.
    Clear enough?
    [you're going to have to] build one heck of a large cargo vessel to hold all the resources needed to keep a human 'population' alive aboard such a slow moving starship for hundreds and thousands of years.
    If the sails are laser-propelled, your cargo vessel could be both smaller and faster over long distances than anything which propels itself only with fuel it carries. Even without laser propulsion, the sails have many uses which do not involve hauling people around. These uses include propelling the probes to locate resources or other points of interest, and hauling the supply stockpiles for people to use when they arrive. The cargo travels by slow boat, the people travel by express.
    --
    Knowledge is power
    Power corrupts
    Study hard
  • This is beyond cool, and I hope this works out. Not only is this a hopeful new technology for space travel, but I get a kick out of how it's being launched from a converted ICBM -

    Turning swords into plowshares...boring. How about turning missles into spacecraft. Now that rocks.

    And to think, this will be the first. I hope NASA gets off their ass if this works. Typical that something so experimental, hopeful, and daring had to come from private funding and not from NASA.
  • Never ceases to amaze me that people are insisting on physical sails for solar sailing, given that there are a slew of problems to contend with. Furthermore, the mission profile simply calls for a deployment test and minimal motion (no plans for a planetary or extrasolar mission).

    Using an M2P2 (Mini-Magenospheric Plasma Propulsion) drive would be a much better choice, because in addition to the lack of launch mass (expensive!), you don't need to worry about deployment problems, and can then think about actually doing some science instead of a publicity stunt. More on M2P2 here [washington.edu] and here [newscientist.com].


    ----------------------------------------
    Yo soy El Fontosaurus Grande!
  • But you do have to admit he/she is improving. It took a line or two today before it was off topic. :)
  • Besides, Einstein did not prove that travel faster than light was impossible. He merely proved that travel *at* the speed of light was impossible.

    It wasn't necessary to prove anything beyond that. An object can't travel at a given speed without first accelerating to that speed (quantum mechanics aside; we're talking about spaceships here).

  • Oh, for christ's sake, it was a joke. You can't tack into a solar wind anyway, keel or no--the aerodynamic effect that allows sailboats to tack upwind is not a property of the photon breeze that pushes a light sail.
  • Reading the various accounts it seems clear that the major objective seems to be testing teh deployment of a large, lightweight structure using inflatable tubes. I'm a bit surprised that they aren't aiming for more than a minor boost in orbital attitude from solar pressure.

    Still, I've often wondered why there aren't more space installations based on inflatable structures. You could build a collosal laboratory in space out of some sort of plastic sandwich (to make it self-healing from micrometeor hits). A structure larger than a football stadium could fit in the shuttle bay and inflated in orbit. You probably wouldn't want to live in one of them (radiation shielding), but you could certainly do materials science and agricultural experiments in one of them. Heck, you could make a giant inflatable wheel and spin it for "artificial gravity"
  • If we are to conquer space, we must develop technologies like this. I was thinking about the issues of exploring space the other day, and it struck me that the problem people have with travelling in space is one of velocity - it just takes too long to get anywhere.The obvious solution is to travel faster, and engineers spend endless time trying to provide us with the technology to do this.

    But there is another way. Instead of travelling faster, we just need to travel subjectively faster. I anticipate that in 20 years time we will have the technology to upload or mindfs into computers, and send digital proxies to the stars, using solar sail technology.

    Of course, the travel time would be thousands of years, but subjectively speaking it would be instantaneous.

    As Einstein irrefutably proved that travelling faster than the speed of light is utterly impossible, some sort of adjustment of our subjective timeframes is the only solution to interstellar travel.

    When the singularity comes, as predicted by Vernor Vinge, I shall be among the first to upload. That way I shall be at an advantage, and may perhaps be able to ascend to the stars on light sail technology.

    Speaking as a transhumanist, I must say that I consider it eminently possible, even probable, that these technologies will develop in the way I have outlined.

    This is a happy day, Gentlemen.

    You know exactly what to do-
    Your kiss, your fingers on my thigh-

  • You fail to see the point. Solar sails are slow at accelerating, but the provide continous acceleration as long as you have a stream of photons behind you. And since space doesn't push on your ship in any other direction, or rather you don't run into anything that causes friction, what seems like an incredibly slow transport method can boost the ship to incredible speeds over long distances.

    As long as the alternative is to bring huge amounts of fuel and burn it over a short period, you will have a point where it for longer distances will be significantly cheaper to build a solar sail powered ship with a sail large enough to get you to your target in the same amount of time.

    And keep in mind that nothing prevents you from for instance using a two stage system, where you do a short, intense burn using a normal engine first, and then deploy the solar sails afterwards to continue acceleration for the remainder of the trip.

  • I am involved in a space project, and we have selected this same launcher. It simply is the cheapest one around at the moment. The Makeyev corporation (designer and builder of the thing) and/or Russian navy have some 200 (I beleive) decomissioned ones left over since the START-I (or -II) treaty. These missiles have to be destroyed, and the simplest way to do this is by launching them. Then, why not put something useful on it? Note that the original launcher is not capable of launching something into orbit as far ads I know. Here, they use a solid-propellant kick stage to achieve that. And about launching from subs; I'm not quite sure why they do that, probably something political involving the navy, missile ownership and free launch training, buit it has been done before. Some German microsats were launched on a Shtil (a larger version of Volna) from a sub in '98 or '99. A number of suborbital microgravity missions have been flown with this Volna.
  • I don't believe this is sad at all, nor is it unprecedented. Corporate satellite launches and private science missions are often launched using non-US technology, such as the French Ariane launch system. One major consideration is cost when making these decisions, another is time. Basically if something can be launched for less when it needs to be launched, rather spend more to wait past the optimal window for launch to use domestic equipment, corporate and private launches will always choose cheap (read: not-as-expensive), reliable, and timely alternatives.

    As far as using a Russian ICBM, I say go for it. ICBM technology can be well adapted to a low-orbital insertion, and it takes another weapon off the tally of the world. I'm not a pacifist typically, but really, if weapons technology can be put to non-weapons use, lets use it.. its already been tested and doesn't need an extensive engineering process to be feasible.


    -----
    I think I'll call this one Bob.

    Live with Love for Love is Life. --mine.
  • I'm reminded of The Mote in God's Eye and the poor little Moties trying to escape their planet on a solar sail powered craft.

    Although facinating to consider, it seems that a solar sail would be of limited use for a two way trip. A solar sail powered spacecraft can't tack against the 'wind' like a sail boat on the ocean is able to do. However, I find the lack of harmful byproducts to be an appealing advantage for solar sails.

    Sailing was the most environmentally healthy way mankind ever developed to traverse large distances, and it seems appropriate that the same techniques be adapted to space travel. I am disturbed when I hear reports of engineers speculating on the construction of atomic weapon powered space craft, or such. We have already despoiled our own planet so utterly; we should keep space in its pristine purity.

    This is precisely the sort of work that scientists and engineers should be engaged in. Rather than just asking what we can do, we should ask what we can do cleanly and well, without causing more of an impact to our environment than necessary.



    - qpt
  • by Anonymous Coward on Tuesday February 27, 2001 @04:56AM (#399013)
    Normal sized spacecraft in Earth orbit have to correct their position and attitude for the effects of solar pressure, along with other disturbances from gravity gradients and residual atmosphere. The solar influence is usually small, we are talking about micro-Newtons, but because the duration is long, it can have a significant affect. Since the largest component area-wise of most satellites are the solar arrays, which are normally about 20 m x 1 m x 2 (satellites are normally symmetrical to avoid rotational disturbance torques) they only have an area of around 40 m^2, compared to over 700 m^2 for the solar sail proposed. I'd suggest this is more than big enough for a proof-of-concept vehicle!
  • by dair (210) on Tuesday February 27, 2001 @04:35AM (#399014)
    it's not that practical for planetary travel, or even interplanetary travel

    This is exactly what it's good for - the speed builds up extremely slowly (it only has the pressure of the solar wind driving it), and so the further you need to travel the more effective it is.

    You need a more maneuvourable (sp?), or faster reacting, engine for that when it comes to landing, emergency procedures, etc.

    You certainly do, but that's not what you would use a sail for. They're intended as a replacement for the long slow burn you need to get to your destination, so you don't need to carry a huge mass of fuel just to get there (instead you can save most of it for the final manoeuvres).

    -dair
  • by Psiren (6145) on Tuesday February 27, 2001 @04:26AM (#399015)
    But get how they plan to launch it: on a Russian submarine ICBM.

    Why is that particular point made? Because its Russian, or because it's an ICBM? Neither seem overly unusual to me. Russians have a good deal of expertise when it comes to space technology, arguably more so than the US. And using an ICBM kinda makes sense. I believe they've been bandying this idea around for quite a few years.
  • by wmoore (45078) on Tuesday February 27, 2001 @05:31AM (#399016)
    The tubes wouldn't have to be that strong if only small pressures are used inside of them. Because space is essentially a vacuum, you can use a very low pressure inside the tubes to accomplish the same thing. It's the difference in pressure that matters.
  • by Hard_Code (49548) on Tuesday February 27, 2001 @05:43AM (#399017)
    "conquer space"

    Oops, you have pushed my critique-of-western-thought button! What is it with "conquering" everything? We have to "conquer" the New World. We have to "conquer" nature. We have to "conquer" space.

    "Einstein irrefutably proved that travelling faster than the speed of light is utterly impossible"

    Well, it was a postulate that has been held up so far, but recent experiments throw inklings of doubt. Beware of absolutes. I don't think much in physics is "irrefutably proved".

    "When the singularity comes, as predicted by Vernor Vinge, I shall be among the first to upload."

    Yes, drink the kool aid...

    It's unfortunate that the west is so fatalistic. I took a look into transhumanism and was at first intrigued, but then got disgusted with its arrogance, fatalism, and irresponsibility. I'm happy being just a plain ol' human. It's this urge to "conquer" to escape and be something else that leads us down all sorts of wrong paths in search of some mythical salvation. bleh
  • by istartedi (132515) on Tuesday February 27, 2001 @06:23AM (#399018) Journal

    Sailing was the most environmentally healthy way mankind ever developed to traverse large distances

    I beg to differ about sailing being environmentally clean.

    The forests of North Carolina were decimated for masts and pitch to build English ships back in colonial times. The interior environment aboard ship was notoriously bad. The name "horse latitudes" comes from the fact that when ships were becalmed, they had to kill horses and dump them into the ocean. Not a pretty site.

    True, oil tankers occasionally befoul beaches. OTOH, the US has more forest today than it did in the 1800s, and that's because we rely on oil and steel, not canvas and trees.

  • by Enigma2175 (179646) on Tuesday February 27, 2001 @04:39AM (#399019) Homepage Journal
    As Einstein irrefutably proved that travelling faster than the speed of light is utterly impossible

    Nobody has ever irrefutably proved that it is impossible to travel faster than c. That it is why it is called the theory of relativity, not the fact of relativity. In fact, I have recently seen articles about scientists accelerating (admittedly massless) particles faster than the speed of light. And the speed of light may actually have a higher limit, check out this article. [space.com] Hardly anything is ever proved, we just refine our theories by observation and hypothesis and we get closer and closer to the truth.


    Enigma

  • by OlympicSponsor (236309) on Tuesday February 27, 2001 @04:43AM (#399020)
    "...Solar Sail powered by light."

    Homer: So, they have solar sails powered by light now.
    --
    Non-meta-modded "Overrated" mods are killing Slashdot
  • by daveym (258550) on Tuesday February 27, 2001 @04:54AM (#399021)
    It seems that this point was made because this is highly unusual:

    #1) It is a Russian weapon system.

    #2) It uses a submarine as a launch platform. How many satellites get launched from submarines?? That is extremely unusual.

    #3) An ICBM is not designed to loft a large-size payload. A set of MIRVs, while very heavy, is relatively compact.

    #4) More to the point, an ICBM is not designed to deliver a payload to space. It is designed to deliver a payload to earth. Why do you think that Alan Shepard's flight lasted only 15 minutes? Because he was sitting on top of a Redstone ICBM.

    So yes, it is overly unusual.
  • by banuaba (308937) <drbork@nosPAM.hotmail.com> on Tuesday February 27, 2001 @04:29AM (#399022)
    Pretty nifty.. But I have a couple of problems/questions..
    It says that the sail is only 30m in diameter. I was under the impression (from reading Omni magazine and Larry Niven, admittedly not the most reliable of sources) that one needed a sail of huge (kilometers) size to be able to get a noticeable boost from the solar sails. Also, the article says that they're using inflatable tubes to unfurl/stabilize the sail. IANAP (IANA Physicist) but wouldn't that make those inflatable tubes have to be tremendously strong to be able to survive in the low-pressure environs of space?

    Those thoughts aside... It's pretty cool. And I wish I could launch my girlfriends cat out of a goshdarned ICBM tube.


    Brant
  • by Chris Burke (6130) on Tuesday February 27, 2001 @06:21AM (#399023) Homepage
    Norad: Umm... We just detected a ICBM launch from the Russian submarine Smirnof.

    Kremlin: Not a problem, comrad! Is just launch of solar-sail you may have been reading about on slashdot.

    Norad: Okay... Umm... Our projected trajectory puts it landing in Washington, DC.

    Kremlin: Is normal! It will separate at high altitude and booster will fire sail into space. Missile will fall harmlessly into Atlantic.

    Norad: Okay... Umm... The ICBM appears to have landed in the capitol, exploded, and wiped out our entire government...

    Kremlin: Is this a problem, comrad?

    Norad: No, not really. Just commenting.
  • by Wog (58146) on Tuesday February 27, 2001 @07:05AM (#399024)
    But get how they plan to launch it: on a Russian submarine ICBM.

    (Jump forward 4 years, under the sea, in a Russian sub.)

    Weapons Officer: Missile number five has been launched. That's one small step for man, one giant-

    Captain: Gustov! You mean missile number nine, right?

    Weapons Officer: Shazbot!
  • by JCMay (158033) <JeffMayNO@SPAMearthlink.net> on Tuesday February 27, 2001 @05:19AM (#399025) Homepage
    I read that link you posted, and I am unimpressed. All they did was prove that the phase velocity of a propagating EM field can indeed go faster than c. The article even mentions the sweeping beam of a lighthouse. If we assume that the beam is rotating with an angular velocity P, then at some point away from the lighthouse r, the linear velocity of the beam v will be equal to c: v = Pr. That's easily determined: r = c/P. Beyond this radius the linear velocity of the beam will be greater than c even though the beam propigation in the r direction will be only equal to c.

    Of course, if you wanted to send a signal faster than c, the group velocity of that EM field would have to exceed c, which it doesn't.

    Since the speed of light, c, is determined by whatever the substance is that the EM field is propagating through by the equation

    c = 1/sqrt(u*e)

    Where u is the permeability of the substance and e is the permittivity. Each of these values is made up of two parts, the intrinsic value and the relative value. The intrinsic permeability of free space (u0) is 1.257e-6 H/m. The intrinsic permittivity of free space (e0) is 8.854e-12 F/m. In a vacuum the relative permeability and the relative permittivity are both 1. This gives a free-space value for c of 2.998e8 meters/sec.

    In a non-vacuuum, either or both of the relative terms will be greater than 1, and the value of c in those mediums will be less than the free-space value.

    The key to propagating signals faster than 3e8 m/sec is to find a material with a dielectric constant (relative permittivity) between zero and 1. These materials don't exist, however.

  • by GeneralEmergency (240687) on Tuesday February 27, 2001 @07:28AM (#399026) Journal

    I was fortunate enough to be in Russia several years ago (as part of a NASA contract) and got to meet and work with Professor Vladimir Syromyatnikov, the father of the Solar Sail, who is one of the most gracious and intelligent men I have ever met. He is truly a brilliant mechanical engineer. His genderless docking collar design is a work of poetry in steel.

    The good professor was kind enough to invite me up to his apartment one day to talk over lunch and meet his wife and family.

    I often think about that afternoon and in particular, one corner of his living room where his television set was placed. There, atop the tv was a VCR and yup, you guessed it, the clock was blinking "12:00". To this day, whenever I need to assess my own failings, I just remind myself "Even Rocket Scientists can't do everything".

    You can email the professor at:
    vladimir.syromyatnikov@rsce.nasa.ru [mailto]


    "A microprocessor... is a terrible thing to waste." --

  • by Eoli (320216) on Tuesday February 27, 2001 @04:15AM (#399027)
    Space.com has more on the subject here [space.com].
  • by Blind RMS Groupie (218389) on Tuesday February 27, 2001 @04:29AM (#399028)
    This is certainly interesting, especially in that it's being done by a private firm, but I find the idea of Mini-Magnetospheric Plasma Propulsion (M2P2) [nasa.gov] much more fascinating. The idea is that you replicate a miniature version of the Earth's magnetosphere around a spacecraft and let the plasma push against that instead. The beauty of it is that thrust remains relatively constant because as the craft moves farther away from the sun the reduced plasma pressure results in a correspondingly larger artifical magnetosphere. Also the thrust can be varied electronically instead of mechanically and there's no moving parts.

    --

  • by vidarh (309115) <vidar@hokstad.com> on Tuesday February 27, 2001 @05:36AM (#399029) Homepage Journal
    Launching from a sub does make sense for several reasons:

    First of all, the Russians do their land based launches from Baikonur, which is relatively far north. Normally, you'd prefer to do launches close to equator to get the maximal benefit of earth rotation. The Russians incur a lot of extra costs because of the position of Baikonur. (and this is also one of the reasons for the orbit MIR is in - they need to get it far enough north to be able to reach it cheaply from Baikonur). Launching from sea means they'll be able to launch from international waters and be independent of having their own land based launch areas near equator.

    Second, there's strict international regulations on such launches, to prevent interference with aircraft. Which you should be happy about the next time you're flying anywhere... :) Launching from sea simplifies things, because most traffic is clustered around or between big cities, and the further out at sea you go, the less flights will pass through the area. So it reduces the administrational issues of ensuring no passenger flights or other aircrafts pass right overhead during the launch.

    Environmental effects and other hazards are always an issue during rocket launches. The rocket can misfire, or explode. Parts may be hurtled through the area in the case of an accident. Dangerous materials or toxic gases may be released as a result of fire etc. Tons of things can go wrong. While it won't be good at sea either, at least you face less immediate threats to human life.

    You also lessen the environmental impact of indigneous animals etc. (which has been a major concern with ESAs Ariane launch site in Central America).

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