Slashdot Log In
Cambridge N-Prize Team To Build Balloon-Assisted Rockets
Posted by
timothy
on Sun Jul 27, 2008 03:19 PM
from the view-is-great-from-up-here dept.
from the view-is-great-from-up-here dept.
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.
Related Stories
[+]
Space On a Shoestring 257 comments
An anonymous reader writes, "Three engineering students from Cambridge University plan to send an unmanned craft into space for £1,000 ($1,880) and have just sent a test mission up 32 km for a lot less. Their snaps from the upper atmosphere are impressive, and were taken by a balloon equipped with off-the-shelf technology including GSM text messaging, radio communications, and an ordinary 5-megapixel camera. They now plan to use a similar craft as a launching stage to get a cheap rocket into space." There's also a video of the balloon launch.
[+]
Low Cost Panoramic Views From 112,000 feet 43 comments
IgorC writes "Some engineering students at Texas A&M University have just received data gathered from a low cost 6 Mpixels digital camera (a Canon PowerShot S3 IS). Via NASA balloon, the camera flew up some 36 kms for 18 hours while storing more than 1600 images. The group writes: ' We are in our preliminary result discovery phase and patched up some of these frames together to produce several panoramic views from that altitude (the camera was looking down). They are viewable on the GeoCam blog. We intend on porting that information on Google Maps and Google Earth. For those of you who are undergrads and want to do something better, the folks at HASP-LSU will have a call for participants next year in their announcement page.'"
[+]
N-Prize Founder Paul Dear Talks Prizes For Nanosat Race 217 comments
Rob Goldsmith writes to point out this interview with Dr. Paul Dear, founder of the N-Prize, and explains: "For those of you who haven yet heard of the N-Prize, the N-Prize is a £9,999.99 (sterling) cash prize which can be claimed by any individual, or group, who are able to prove that they have put into orbit a small satellite. The satellite must weigh between 9.99 and 19.99 grams, and must orbit the Earth at least 9 times. This project must be done within a budget of £999.99 (sterling)."
Submission: Cambridge University to Build Balloon Spaceships by Anonymous Coward
This discussion has been archived.
No new comments can be posted.
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
Full
Abbreviated
Hidden
Loading... please wait.
Inflation (Score:3, Insightful)
Re:Inflation (Score:5, Informative)
"Receipts must be produced, if requested, for all items or services purchased which fall within the ã999.99 budget"
http://www.n-prize.com/rules_in_full.html [n-prize.com]
So if you get a receipt from the fuel you used in the winning flight, it doesn't matter if the price goes up. If however you fail and you need to buy more fuel to try again, then the increase in price would be a problem to you.
Parent
Re:Inflation (Score:4, Interesting)
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:
"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.
Parent
Re:Inflation (Score:5, Insightful)
Parent
Re:Inflation (Score:5, Insightful)
This was a politely worded post. You worded this in a non-inflammatory manner and explained why you feel the way that you do, did not use invectives or name-calling and did not even take a very controversial position, and yet you were still modded as Troll. This is one of the better statements on the recent quality of Slashdot moderation that I've seen in a while. You point out that they were not applying the moderating guidelines and they respond by failing to apply them some more, without ever explaining why they disagree with you because they probably realize they would not have a leg to stand on. I'm fully expecting to get modded to -1 myself for pointing this out, but that's okay. I have karma to burn and I'll feel better for having done it since I believe this sort of bullshit needs to be called out wherever it occurs.
Parent
Re: (Score:2)
I agree with the essence of what you are saying, but must point out that Slashdot's moderation system does not allow one to both comment an article AND moderate in the same comments section without nullifying their moderations. Thusly it a person who issues a dissenting
Re: (Score:2)
Both posts happen to be factually incorrect.
This is why there's a mod called "OVERRATED". Troll should be used for trolls ONLY. And BTW, this is why I wish there was a "-1, incorrect" mod.
Re: (Score:2)
Re: (Score:2)
To get to the first level of offtopic, I think he may have a point but the problem with claims like that is proving them which is impossible because if the government can print money to fight a war, they can cover it up in bureaucracy until not even they know who is cheating and who is not.
And on topic, they should market this
Re: (Score:2)
That doesn't make it a troll.
The "World Banker" rant was not moderated troll--it was moderated offtopic. However, deliberately giving blatantly false information certainly qualifies a poster as "troll-kin" in my book.
Re:Inflation (Score:4, Informative)
By the way, the Federal Reserve is a private corporation....
The Federal reserve is a government institution--your assertions to the contrary are false (and the "World Bankers" drivel is sheerest bullshit). (Cite [wikipedia.org])
Parent
Re: (Score:2)
It is neither. It is privately owned and held...
Try again. "The Federal Reserve System is an independent government institution that has private aspects, but is neither a private organization, nor operates for a profit." Cite. [wikipedia.org]
as are the member banks.
Try again. Many of the member banks are not privately owned, but publicly-held and publicly-traded corporations.
It operates independently from the government with little oversight other than selecting appointees.
Try again. "Congressional oversight and statute, which can alter the Fed's responsibilities and control, allows the government to keep the Federal Reserve in check." (Ibid.)
In your linked article there is a notable quote by Ron Paul, who is rather outspoken on the problems with the Federal reserve system.
it's very secretive. As a member of congress, I can find out more information about what the CIA is doing than what the FOMC is doing, the central bank, what they're doing on monetary policy
Paul's objections to the Fed are not only well k
What would anyone do with 10-20 grams in orbit? (Score:4, Interesting)
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.
Re:What would anyone do with 10-20 grams in orbit? (Score:5, Interesting)
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
Parent
Re: (Score:3, Informative)
It was apparently big enough to take pictures, and Governments notice that too. [slashdot.org]
Hmmm. (Score:2)
40 lbs coming in the RIGHT fashion from orbit, can do a LOT of damage.
Re: (Score:2, Insightful)
E=mc^2 would only be relevant if the payload consisted of antimatter. And producing antimatter on that scale is far beyond our current capabilities.
I think the formula you're looking for is (1/2)mv^2 [wikipedia.org], with a high value for v.
Re:What would anyone do with 10-20 grams in orbit? (Score:4, Interesting)
When you have a 2+ meter dish with high-gain LNBF properly aimed, you can pick-up a radio signal from a wrist watch...
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.
Parent
Re: (Score:2)
Good job satellites don't have satellite dishes mounted to face the earth...
Couldn'tthe surface of a satellite (cylindrical or spherical) reflect radio waves ....
Re: (Score:2)
Can you even make a transmitter + power supply that small that would still be powerful enough to communicate with the ground
Yes.
And even if you couldn't:
I'm not really sure what the point of this is
This really ought to get you barred, you know.
Re: (Score:2, Insightful)
"I'm not really sure what the point of this is...what is anyone going to do with 10-20 grams in orbit?"
I couldn't disagree more. Getting anything into orbit for less than 1000 GBP has a great number of uses. Several "pico-satellites" have been put in orbit, of which the various CubeSats http://en.wikipedia.org/wiki/CubeSat [wikipedia.org] are good examples. These use relatively inexpensive equipment and the lightest of them are only a few hundred grams so I do not think it ridiculous to envisage someone developing a 20 gra
How much does the balloon help? (Score:2)
Re:How much does the balloon help? (Score:5, Informative)
Parent
Re: (Score:2, Informative)
One advantage I might imagine is that pulling a rocket up even a few kilometers and launching from there puts you above a large part of the atmosphere. Atmospheric density decreases exponentially height (http://en.wikipedia.org/wiki/Barometric_formula), so for example, at 5 km, the rocket only has to cross half the atmosphere, reducing drag a great deal. Naturally, the rocket must still accelerate above escape velocity (which is not significantly changed at 5 km above sea).
Re:How much does the balloon help? (Score:4, Insightful)
Achieving orbit is not about how far away you are away, it's all about your angular velocity. You could theoretically achieve orbit at sea level, but atmospheric drag keeps that from happening on earth.
As satellite orbits the Earth, it is constantly accelerating, not because its speed is increasing, rather because it is constantly changing direction (speed + direction = velocity, change in velocity = acceleration).
The acceleration of gravity is 9.8m/s, so if you can achieve an acceleration of 9.8m/s in the opposite direction, you will be in constant free fall and establish an orbit.
It takes a lot of energy (32MJ/kg) to sustain this acceleration on Earth and maintain an orbit. However, you are correct that it takes less energy to enter into a geo-synchronous orbit than other types of orbits from different latitudes. Sorry I can't find a reference for it at the moment though.
Parent
Good luck (Score:5, Interesting)
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.
Re:Good luck (Score:5, Informative)
The idea behind balloon launched rockets has nothing to do with escape velocity/gravity. It has to do with aerodynamic drag. Aerodynamic drag plays a big role in eating up launch fuel at lower altitudes where the atmosphere is dense. A balloon launch bypasses that drag with a low cost, and disposable, balloon filled with hydrogen/helium without having to use expensive/heavy rocket fuel. The concept was developed and first implemented in 1949 and has been done a number of times since for high altitude experimentation and hobbiest projects. Wikipedia has a basic article inder the, somewhat archaic, name "rockoon" (mixture of rocket and balloon).
Parent
Re: (Score:3, Insightful)
There's two problems with this scheme
Re: (Score:3, Interesting)
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.
Re: (Score:2)
Yes necessarily. Being hundreds of thousands of tons of lifting force, it will require considerable (fairly heavy) structure to distribute that force across the lifting envelope and transfer it to the payload.
Re: (Score:3, Insightful)
Yes necessarily. Being hundreds of thousands of tons of lifting force, it will require considerable (fairly heavy) structure to distribute that force across the lifting envelope and transfer it to the payload.
It would require a support rail to attach the rocket. That part would be recoverable if desired. It would not require the outer skin (certainly not the iron oxide and aluminum paint!) control surfaces, engines, passenger gondola, etc.
Sure. In the same way my pocket calculator resembles a Cray supercomputer.
The computer I'm using now is much more powerful than a Cray from the '80s :-)
Re: (Score:2)
The individual cells or balloonets that contain the lift gas aren't c
Re: (Score:2)
No one here has suggested trying to lift Atlas boosters with weather baloons (although the other response to your post suggests that it might, theoretically, be possible). Whats is being suggested here is no different than what was tri
Re: (Score:2)
Did it ever occur to you there's a reason why Rockoon was abandoned? Rockoons were attractive in the 40's and 50's when producing the rockets with the needed performance was difficult, but t
Engine geometry and air pressure (Score:5, Interesting)
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.
Parent
Close to the ground for BIG rockets (Score:5, Insightful)
The "burn most your fuel close to the ground" only applies to big rockets that are having to use early fuel to get later fuel up to altitude.
In the present case both those assumptions are violated, making their approach more sensible than it sounds. First off, for a big rocket most of the energy required will be used to 1) get up to speed and 2) gain altitude, with 1) being the biggest concern. For a small rocket, both of these will initially be swamped by 3) friction. The higher you are when you start, the less of your fuel you will waste just overcoming drag.
Secondly, the rule only applies when you are gaining the altitude by burning fuel in the first place. When you aren't having to burn fuel to get up there, you'd always come out ahead launching from a balloon (or even a mountain top) provided you could figure out how to make it work. Heck, with a tall enough tower (hint: think GEO) based on the equator, you could launch a satellite by hand!
--MarkusQ
Parent
Re: (Score:2)
"...The energy savings from using a balloon are only a small percentage of the overall energy required to achieve orbit..."
You are looking at this from a university "Physics 101" perspective. If you were an engineer you would not be allowed to "neglect the effects of the atmosphere" These effects are...
1) There is a huge amount a friction drag. You have to fly through many tens of miles at high mach numbers, this require a lot of power.
2) Because of #1 above the vehicle must be quite strong with a struct
Cost per kilogram (Score:3, Informative)
This wouldn't even make too much sense since
with that kind of money a kilogram in orbit would cost around 50000 pound. There are much cheaper means of getting to orbit:
http://www.futron.com/pdf/resource_center/white_papers/FutronLaunchCostWP.pdf [futron.com]
Interestingly small launchers seem to be less efficient than larger ones on average.
Maybe one should just try to hitch a ride.
On the other hand this seems to be a fun project.
I hope they are successful.
Re: (Score:3, Insightful)
It seems to be an attempt to open up space launch capability to the little guy. Sure, when you look at the numbers, those big launch vehicles seem to be down-right cheap per lb., but good luck getting your 1lb. hobby project onto one of those launches. The organizations responsible for launching those rockets are, most likely, working exclusively with companies and fellow governments that need to launch 100lb+ payloads. Even if they'd work with an individual/small business, the red-tape and per-project o
Re:Cost per kilogram (Score:4, Interesting)
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.
Parent
Re: (Score:2)
>Secondly, it's unlikely that if 20g to orbit is $2000, 200g to orbit will be $20000.
My assumption was that this rocket is either your only means to space and you have to assemble in orbit (I don't know how), or that for comparison you hitch a ride and pay by weight. Then having the Kg to orbit price helps comparing your options. However I doubt that you can get away with only paying for the weight, probably they let you pay for a part of the launch service and that won't be cheap.
Also I just read somewh
Space Pollution (Score:2)
Just as we're making some progress with the atmosphere, the N-Prize comes along to encourage any idiot with 1k quid to fire an unguided projectile into the same part of space where multi-billion-dollar satellites are passing by at relative speeds of over 20,000 mph.
If a major satellite exploded and much of the shrapnel remained in orbit, in time it would collide with another major satellite, creating more shrapnel, before you know it satellites become unfeasible, and we step back several decades in a few hu
Re: (Score:3, Funny)
"And here's the 2-2 pitch, oooh boy, Johnson's been decapitated by a fallen solar panel, drat the luck. Leiter steps in in relief. Brought to you in ultra-low def by Comcast."
How about going the other way? (Score:4, Funny)
William Gibson had a similar idea: (Score:2)
I think I saw this in Batman (Score:2)
Didn't he use it to get out of that building in China?
Fine, you want content? Seesh.
Cheap access to space is good, but maybe this is too cheap. We don't just let any dude buy and fly a plane, a car, or even a boat. Except space is different: you're so high up that if you fuck up it can affect people literally halfway around the world.
Just look at the pain it is to travel between countries by plane. Governments will be foaming at the mouth if this ever turns into something useful (OMG MISSLES) and we can bar
Re: (Score:3, Insightful)
I, for one, welcome our new balloon rocket overlords.
Otherwise known as BOC and Cambridge Precision [ucam.org] .
I can see the usefulness of sponsorship by private enterprise, and it's reasonable to expect the sponsor to want their name on the craft, but this is ridiculous.
Re: (Score:2)
Re: (Score:2)
Re: (Score:3, Insightful)
But a cellphone cam might just work.
A cell phone CCD will be about 20 grams. But you also need the decoder, the DSP, and the transmitter, and the battery. If you still manage to do all that, then what's the use of a low-res image from 400 km? I understand that it might be cool once or twice, but that's what amateur satellites are for (this includes ham [amsat.org] and non-ham [stanford.edu] ones.) These satellites don't weigh 20 grams - they are larger, but they actually work.
Usually amateur satellites hitch a ride on some oth