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Space Science Technology

Cambridge N-Prize Team To Build Balloon-Assisted Rockets 93

Rob Goldsmith writes "Earlier this week we heard that Cambridge University Spaceflight would be entering the N-Prize competition. The N-Prize is a competition to stimulate innovation directed towards obtaining cheap access to space. Most importantly, the launch budget must be within £999.99. Cambridge University Spaceflight plan to win the prize using a balloon and a rocket. They have now opened up an official forum where the public can track their progress." The linked story has images from a test flight of July 23, and an interview with a member of the team, Ed Moore.
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Cambridge N-Prize Team To Build Balloon-Assisted Rockets

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  • Re:Inflation (Score:4, Interesting)

    by Anonymous Coward on Sunday July 27, 2008 @04:46PM (#24360933)
    What if someone did it for just under ã999.99 but then the price of say rocket fuel goes up?

    The price of fuel hasn't really gone up very much, if at all. What's happened is that the money supply has increased, causing major inflation. The "War on Terror" in Afghanistan and Iraq and federal government bailouts of large banks were financed by "printing" (most of it is electronic actually) money from NOTHING and then spending it, which the Federal Reserve is more than capable of doing (so are other banks; see Fractional Reserve Banking [wikipedia.org]). When you keep doing that with hundreds of billions of dollars, it devalues the currency because there is X amount of wealth represented by Y amount of dollars in circulation. If Y increases while X does not increase or increases more slowly than Y, then each dollar is worth less than it was previously. Yes they are a cartel, yes they control the market by carefully adjusting how much oil they produce, but for the recent oil price hikes we keep hearing about in the media, OPEC is merely adjusting their prices to match the current value of the American dollar.

    By the way, the Federal Reserve is a private corporation, which means that allowing them to print money and control our currency is UNCONSTITUTIONAL because only the federal government has this power. They are one part of a worldwide organization known as the World Bankers which controls the currency of almost every "industrialized nation" on the planet. Like most threats we face today, the founding fathers warned us about this one:

    "I believe that banking institutions are more dangerous to our liberties than standing armies. If the American people ever allow private banks to control the issue of their currency, first by inflation, then by deflation, the banks and corporations that will grow up around [the banks] will deprive the people of all property until their children wake-up homeless on the continent their fathers conquered. The issuing power should be taken from the banks and restored to the people, to whom it properly belongs." -- Thomas Jefferson

    "Deprive the people of all property". Sound familiar? How's that mortgage market doing these days?

    Basically, if you can create economic crises and social unrest, if you can bankrupt a nation anytime you want, you can take over that country without having to fire a single shot.

  • by nasor ( 690345 ) on Sunday July 27, 2008 @04:56PM (#24361009)
    I'm not really sure what the point of this is...what is anyone going to do with 10-20 grams in orbit? Can you even make a transmitter + power supply that small that would still be powerful enough to communicate with the ground? Or are you just supposed to send up 20 grams of foil or something that can be tracked with ground radar?

    The X-prize was about getting people into space, which I think most people can see uses for (even if it was sub-orbital). I'm not really sure about this. Although I guess it's a great way to get a lot of free publicity, especially since the odds of anyone actually claiming the prize money are very low.
  • Good luck (Score:5, Interesting)

    by TimeTraveler1884 ( 832874 ) on Sunday July 27, 2008 @05:02PM (#24361057)
    I'll admit, I don't know what the N-Prize is and I did not RTFA; I am assuming the goal is to reach some kind of sub-orbital or LEO flight. I've looked in to this for my own balloon projects. The energy savings from using a balloon are only a small percentage of the overall energy required to achieve orbit.

    It takes about 20 times the amount of energy [wikipedia.org] to reach LEO than it does to just reach the same altitude. When you compare this energy requirement to the savings of launching from the ceiling height of a weather balloon [wikipedia.org] (40km) it is not much; especially considering you still have to get to the Karman Line [wikipedia.org] (100km) plus the weight of fuel required, which must then be lifted by even larger balloons. Therefore, it's more economical and efficient to burn the fuel as close to ground as possible [wikipedia.org].

    I'm only an armchair rocket scientist though, so I might have this all wrong. In any case, I certainly wish them good luck - Maybe I'll go read the article now.
  • by viking80 ( 697716 ) on Sunday July 27, 2008 @05:38PM (#24361289) Journal

    You are correct in your energy estimates, but a high altitude balloon launch has other significant advantages:
    1. Your rocket engine can be an engine with vacuum geometry meant to work well in space. This differs from an engine meant to operate at low altitude.
    2. Your rocket design does not need to include complicated supersonic flight in dense air, so your vehicle can be more optimized for the mission at hand rather than aerodynamic.

  • by Squarewav ( 241189 ) on Sunday July 27, 2008 @05:39PM (#24361305)

    I think the point, if there is one, is they wanted the rockets to have a payload and not just be a cylinder filled with rocket fuel. As for the size, I'm assuming its low to not only make it easier to achieve but to avoid people being accused of making missiles. Governments have a tendency to take notice when people build rockets large enough to carry explosives

  • by evilviper ( 135110 ) on Sunday July 27, 2008 @07:52PM (#24362313) Journal

    Can you even make a transmitter + power supply that small that would still be powerful enough to communicate with the ground?

    When you have a 2+ meter dish with high-gain LNBF properly aimed, you can pick-up a radio signal from a wrist watch...

    Or are you just supposed to send up 20 grams of foil or something that can be tracked with ground radar?

    It wouldn't be a bad idea to send up something like a concave sheet of metal (aimed towards the planet) to use as a simple signal reflector. I'm sure hams and DXers would love the idea. It would be a lot easier and more consistent than bouncing signals off the moon.

    It would be a very interesting world if we had a significant number of those in orbit. From the comfort of your living room, you could listen-in to any radio signals, being broadcast anywhere in the entire world, provided only that you have equipment that is sensitive enough to pick the weak incidentally reflected signal you want, out of the background noise.

  • Re:Cost per kilogram (Score:4, Interesting)

    by queazocotal ( 915608 ) on Sunday July 27, 2008 @08:07PM (#24362383)

    Cost per kilo is somewhat missing the point.

    Firstly, you can't buy a kilo to orbit. You simply can't.

    You may be able to beg a ride-along if you have the right political connections, but otherwise it's impossible.

    Secondly, it's unlikely that if 20g to orbit is $2000, 200g to orbit will be $20000.

    Thirdly, and perhaps most importantly.

    20g to orbit can't do much. You can put a bad camera, a radio, a solar panel, and a magnetometer on it, and maybe if you push the envelope really hard a 3-axis gyro. (to calculate your orbit)

    200g however, even if it was $10000 per flight is in the realm where universities with modest physics, aerospace, or electronics facilities might consider it interesting to put up a small test sat.

    Your cellphone weighs under 200g, even if it has GPS, GSM, accellerometers, wifi, camera, ...

    With 200g in a small satellite, you've got a good shot at a reasonable camera, stabilisation using the earths magnetic field, GPS, a much better radio, solar panels, batteries to keep it alive during dark.

    It's even reasonable that you could have a small part of it - say 50g - as a single-shot rocket able to optimise the trajectory.

    I note that http://www.rcgroups.com/forums/showthread.php?t=814157 [rcgroups.com] there are amateur build fully remote controlled planes at under half a gram.

  • Re:Good luck (Score:3, Interesting)

    by sjames ( 1099 ) on Sunday July 27, 2008 @11:55PM (#24364007) Homepage Journal

    A disposable Hindenburg would cost tens of millions of dollars - while the few thousand gallons of fuel and oxidizer it replaced would cost a few thousand dollars.

    Not necessarily. Being disposable, it wouldn't require much structure or external protection. It'll be destroyed long before damage can accumulate. It would mostly resemble weather balloons. The Hindenburg cost more, in part, because it was expected to see years in service.

A committee is a group that keeps the minutes and loses hours. -- Milton Berle