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Cambridge N-Prize Team To Build Balloon-Assisted Rockets
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.
What if someone did it for just under £999.99 but then the price of say rocket fuel goes up?
I, for one, welcome our new balloon rocket overlords.
Otherwise known as BOC and Cambridge Precision .
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.
Loose lips lose spit.
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.
Are there any rocket scientists here who could enlighten us about how much the balloon would really help with getting something into orbit? As I understand it, the problem with getting into orbit is that you have to get going really really fast - it's not just a matter of being up really high.
What was once old, is new again.
Sig this!
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 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 (40km) it is not much; especially considering you still have to get to the Karman Line (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.
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.
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
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.
Je me souviens.
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.
don't cut it off www.mgmbill.org
I love the open source ethos of this project, but I wonder about the wisdom of letting every Tom, Dick, and Harry shoot stuff into space. In most places there would at least be laws against some yo-yo shooting up trash on purpose, I also have to wonder about a bunch of pseudo-terrorists of the Luddite variety wanting to crap-up space just because they hate technology, spy satellites, etc.
The obvious problems are a) Some people probably said the same thing about the Wright brothers and b) People are going to figure this out at some point anyway, so this prize will (at most) just hasten and publicize this capability.
The next prize should be one for creating an affordable galactic garbage truck.
in how you use the heat. Focus the suns rays on a pipe with water running through it and then what? I built a solar air heater using popcans for $80 and use it during the summer to heat water and during the winter it heats and recirculates air in the house. Here is a solar heater someone else built (same thing here) http://www.fieldlines.com/story/2007/8/20/124818/249
What value can humanity obtain from you posting on Slashdot?
Discussion of issues leads to prudent decisions.
If the budget is 999 pounds (which is, what, 2000 bucks I think?) to access space, then now is the time to release the warp field technology I've been perfecting in my lab. I'll be the dude who changes the world when some folks from the planet Vulcan pass by Saturn and notice my warp-speed ship flying towards some darn place or another. I think 999 pounds is a typo. There's no possible way, hot air balloon or not.
McCain/Palin '08. Now THAT's hope and change!
Prime Minister, is that you?
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
What can be done in 20g?
What can't?
There are obvious limits.
You're not going to get a nice big lens on there for a decent camera. But a cellphone cam might just work.
You can't get active control of your orientation. Though with the above camera, and a couple of magnetic field sensors, combined with software, you can tell which way you're pointed.
You won't be able to send back large amounts of data - but a small pic or two per orbit, commanded by the ground should barely be possible.
As to what can be done in something slightly bigger - the sky is the limit. (or not).
I note that people have made complete flying R/C planed under half a gram.
If these people had relatively cheap access to orbit, what might happen?
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 hundred fields of science and communications.
Satellites from their inception have taken damage from microscopic "space dust", and the term "space pollution" was coined, with the dire potential consequences of making near outer space unusable, not to mention the constant falling debris.
War as we knew it was obsolete
Nothing could beat complete denial
- Emily Haines
How about rocket-assisted balloons? That would probably be a lot of fun, too.
I continue to be amazed by William Gibson's vision.
I highly recommend this short story, and his entire short story anthology "Burning Chrome."
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 barely hold back from blowing each other up as it is.
Still, this is too light to be useful. But it won't be for long...
I have developed a truly marvelous proof of this comment, which this signature is too narrow to contain.
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 and non-ham ones.) These satellites don't weigh 20 grams - they are larger, but they actually work.
Usually amateur satellites hitch a ride on some other commercial launch, for a fraction of cost. There is no need to invent yer own rocket for $2,000 - use already developed hardware that works for real. Besides, rocketry is not a safe hobby when you deal with enough propellant to lift something to an LEO. When you try to do it on the cheap things only get scarier.
On subject of RC planes: a half a gram RC plane only needs to receive, so its power budget is not as tough as a satellite that has to have a large antenna and/or a powerful transmitter to send its status and data back to Earth. But half a gram RC plane is still an achievement, and it is useful because you can fly it and enjoy its flight. People are free to make a 20g satellite also, but it will be far less useful than a tiny RC plane.
E=MC^2.
40 lbs coming in the RIGHT fashion from orbit, can do a LOT of damage.
I prefer the "u" in honour as it seems to be missing these days.
So get an enormous hydrogen balloon and use it to lift another balloon of oxygen plus a rocket engine.
Use the rocket engine to increase the orbital velocity of the rockoon, as the orbital velocity increases, the whole kit and caboodle would spiral outwards.
I am not a rocket scientist nor a mathematician, so I would ask all those far cleverer than me, how big would the hydrogen balloon have to be, to get the whole thing to geostationary orbit.
As an aside, a hydrogen balloon would be a cute way, to take water to the desert.
Iceland has lots of electricity, they say they are going to use all that spare electricity to smelt aluminum, no - use it to extract hydrogen from the sea.
Use the potential energy that exists in the hydrogen, to fly the balloon to an area of desert, then you use the oxygen that all ready exists in the desert and connect it to the hydrogen, that is in the balloon, viola you have taken both energy and water to the desert.
It's called an elephant's trunk whereas it is in fact, an elephant's nose, a nose by any other name would smell as sweet
I understand your frustration with moderation abuse. But it certainly seems to me that a reasonable moderator could, in a story about the N-Prize, consider a question about the rules on topic and a rant about the Federal reserve offtopic.
But a cellphone cam might just work.
A cell phone CCD will be about 20 grams.
No it won't. .25g tops.
The ST VS6555R0H9 for example. VGA, 4.5*4.5*2.5mm, I'd guess
There are slightly larger cameras going up to a couple of megapixels.
But you also need the decoder, the DSP, and the transmitter, and the battery.
Decoder, DSP, and micro I can directly address, as I have a board using a similar (but 2MP) cam about to go for production that is now about 4 grams, 5 including the microSD.
If I put maybe $400 into weight reduction, and build them by hand I can drop that to around 3.5 grams, including an 8GB microSD.
If you still manage to do all that, then what's the use of a low-res image from 400 km?
I'm tempted to drag out the famous quote 'What's the use of a newborn baby' - with regards to electricity, but that's way overstating the case.
At the moment, it's complex and hard for small organisations (say a medium sized electronics department in a university) to get anything launched.
I hope by vastly reducing the entry burden that more people will start innovating - where there is little at risk, there can be lots of risk-taking, much as the computer industry only exploded when computers got cheap enough that innovation in software got cheap.
Yes, you can beg for a ride-along, but this is not cheap in terms of effort you need to put in to it. (and that time costs money too).
Besides, rocketry is not a safe hobby when you deal with enough propellant to lift something to an LEO. When you try to do it on the cheap things only get scarier.
This is of course an issue.
However, constraining the rocket element to perhaps 10Kg, with a thrust profile meaning that it cannot hit the ground under power, selecting appropriate launch sites, and ensuring a low burnout weight will all greatly mitigate risks.
On the subject of mass budgets, which you raise.
More precisely "Songs from the Stars" by Norman Spinrad.
Any earlier reference?
--
El Guerrero del Interfaz
Really?
Its a govt entity? then where is its SEC filings and members who make profits?
They are granted legal right to print money, ie, legal counterfeiting as such. They are still goons.
Anyone, I dont care, since you will be stuck in the waste land. Its all of americas corporates and bankers who have already stolen trillions and are in the caymen islands.
Enjoy paying of the loans for decades.
Liberty freedom are no1, not dicks in suits.
bankers run the planet, like they did since Napolian.
hopefully this is the last time, and those aliens come down, and rape their ugly asses till they bleed.
They zap em to a black hole somewhere.
Liberty freedom are no1, not dicks in suits.