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Solar Sail Craft Damaged

C. Mattix writes "It looks like we won't know if the solar sail will work for a while. There was an accident prior to launch that will delay it for quite some time. Full story from Yahoo."

11 of 54 comments (clear)

  1. I suspect the Russians by Anonymous Coward · · Score: 4

    It's too big a coincidence that an accident like this would happen right when America was trying to launch its next generation of space craft. There are no coincidences in this world. It must have been Russian sabbotage.

    The Russian space agency must be reeling, now that MIR is out of the sky. They were once a proud nation with a proud space heritage, but now they're a third-world grounded nation begging for international aid from the west. That has to hurt.

    So what do they do? They sabbotage America's glorious space program. They're jealous of our potential and they're jealous of our success. They never forgot that we were the first nation in history to successfully fake a moon landing, and they won't forgive us NASA's recent successes with missions to Mars. Worse than that, we insulted their collective genitalia with Taco Bell's publicity stunt which put a target in the Pacific ocean for MIR to land on.

    NASA is far too clever to have caused this accident by their own incompetence. America is too strong a nation to let such accidents get in the way of our manifest destiny. We must find the spy who committed this act of terrorist espionage and bring him to justice.

    The Cold War is very much alive.

  2. Re: Not hot enough for ya? by hawk · · Score: 3
    >The energy density at the focal point is inversely proportional to
    > the square of the distance is it not?


    No, it is not.


    That is the density for a point source that is radiating in three dimensions. For a lossless focused mirror, the density would be the density at the point of the reflector times the ratio of the area of the reflector to the area of the target. This has to be adjusted for losses at the mirror (less than full reflectivity) and through the air (you hit molecules and disperse, and what's left will be ionizing the air near the target).


    hawk, actually a physicicst among his many hats.

  3. well at least we now know.. by mandolin · · Score: 3

    that the pyrotechnic circuits work.

  4. Re:This is not NASA by PD · · Score: 3

    You don't need to expend fuel to change the orbit. Put some solar cells on your spacecraft, and you can send a current down the wire to act against the magnetic field. How about that? You've used solar power to maintain your orbit. This is a neat tether trick which would be very useful.

  5. Re:Good, solar sails are too dangerous to be allow by Speare · · Score: 3

    The solar foils added to ISS/Alpha recently were half an acre in size. This means that if aligned nicely, you can see ISS/Alpha with your unaided eyes. Oooh, the danger. I'm afraid.

    If you can focus all of the solar light that hits an earth-acre space, into a much smaller space (say, a 3' square) on the ground, yes, it's gonna be hot and perhaps dangerously hot. But not weapons-grade dangerously hot.

    You've been reading too many scifi novellas.

    --
    [ .sig file not found ]
  6. This is not NASA by Chairboy · · Score: 3

    Keep in mind, this is not a NASA project. This is a privately funded experiment. NASA has no interest in really pursuing new propulsion techniques. That's why the ISS hasn't been (or isn't even planned to) outfitted with a MEDS style electrodynamic tether for orbital maintenance. An EDT would reduce (if not remove) the dependance on costly space shuttle and Progress space freighter flights to boost its orbit against atmospheric drag.

    An interesting note, this solar sail is to be launched atop a former ICBM from a submarine. That, my friend, is the essence of cool.

    1. Re:This is not NASA by DESADE · · Score: 3



      I always wondered why we never heard more of this. From my understanding, the basic concept was dragging several mile long tether through the earth's magnetic field, generating electricity. From what I heard, they energy produced was so much greather than what they expected, the tether broke and the circuit breaker tripped (is was supposedly rated at a very high rate too).The experiment was not a failure, they just underestimated the energy that would be produced.
      This experiement seemed to have shades of Tesla written all over it (ie The earth is a giant capacitor), but I never heard anything more.

    2. Re:This is not NASA by s20451 · · Score: 5

      Actually there were space shuttle experiment in 1992 and 1996 to study the use of tethers. Look here for more. I believe at least one of these experiments ended in failure when the tether broke; both tethers and solar sails are highly susceptible to micrometeorite impacts.

      NASA has also flown experimental ion propulsion technology on the Deep Space 1 mission, and has a research team at JPL investigating advanced propulsion concepts. You may have heard of a proposal for magnetic-assisted propulsion to travel to Pluto; IIRC that was one of theirs.

      I don't know of any NASA attempt to use solar sails, though.

      --
      Toronto-area transit rider? Rate your ride.
  7. Don't know if this is the case by HerrGlock · · Score: 3

    But some of the prototypes that are overhyped, the makers of the item find a fatal flaw just before the maden use of the item and 'accidentally' damage it, delaying the use of it. Then they get the time to fix it with the update or patch that it requires.

    Saves them from the embarassment of launching something that will not work. On the other hand it does end up with a correct item that works as expected so everyone is happy.

    Again, just something to think about.

    DanH
    Cav Pilot's Reference Page

    --
    Cav Pilot's Reference Page
    UNIX - Not just for Vestal Virgins anymore
  8. Good, solar sails are too dangerous to be allowed by typical+geek · · Score: 5

    I'm glad it hasn't been launched, solar sails are far too dangerous to be allowed in orbit.

    Before you condem me, think of the facts. They are talking about orbiting a huge, acre sized, piece of mylar, with controls to change it's orientation.

    It's a giant space mirror!

    For those of you didn't read the Mars trilogy, think back to the first time you played with a magnifying glass in your backyard.

    Now, scale that up to a beam of light, a yard wide and more intense than a steel melting laser beam. Think what the beam of light could do to any cities or countries that don't kow-tow to the US-Russian space hegemony.

    Worried yet?

  9. Thus... by Dancin_Santa · · Score: 5

    Thus proving what we developers already know: QA is the cause of all our problems.

    Dancin Santa