Space On a Shoestring 257
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.
Moo (Score:5, Funny)
Re:Moo (Score:4, Funny)
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You can just see the kind of flap someone in Cambridge could get in if the found a small box with a battery and a bunch of wires hanging out, on the roof of their car in the morning. Tee hee
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Which, after years of research into improving the message, has been changed to "Mostly Harmless Scientific experiment...".
Re:Moo (Score:5, Interesting)
Re:Moo (Score:5, Funny)
Re:Moo (Score:4, Insightful)
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The equation for the motion of a falling body is F = -mg, where m is the mass and g is the acceleration constant 9.8 m/s.
Now, we can't neglect air resistance, but we'll simplify it. It increases as you get faster, and depends on several other factors
like air density, and the cross section of the object, etc. We'll lump all of that into the constant c, so we have a force opposing
gravity cv (which, in some cases is cv^2).
This gives us the equation F = cv - mg, which is a differential
Very cool hobby... (Score:5, Informative)
http://www.grc.nasa.gov/WWW/K-12/Numbers/Math/Math ematical_Thinking/designing_a_high_altitude.htm [nasa.gov]
http://www.amsat.org/amsat/balloons/balloon.htm [amsat.org]
Re:Very cool hobby... (Score:5, Interesting)
Ballons need permission?? (Score:3, Informative)
Re:Very cool hobby... (Score:5, Informative)
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Re:Very cool hobby... (Score:5, Funny)
Seems that FAA notification is easy (Score:4, Informative)
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Ya know, in the grand Slashdot of life, aren't we all karma whores at best?
The parent supplied useful information, albeit in such a way as to boost his karma. It's better than some "designer" "offend everybody" troll post (with little four letter acronyms & whatnot).
GSM text messaging (Score:5, Interesting)
Why do we need inflight GSM mini stations then?
Re: GSM text messaging (Score:5, Insightful)
Anyone familiar with the story of flight 93 knows that cell phones work at the cruising altitude of commericial jet aircraft.
Lee
Re: GSM text messaging while flying (Score:5, Interesting)
Outbound from where I live on a Nokia 6230 I had signal for a decent phone call up to ~5,000 feet and could send SMS to around ~6,000 feet, soon after this I lost signal. Leaving on the way back to here I had phone signal for a call up to ~7,000 feet and lost phone and SMS at about the same time.
The Blackberry 7230 I had with me made it another 500-1000 feet over my Nokia in regards to signal though GPRS didn't fare so well. Luckily Brick doesn't require phone signal.
We tended to fly at around 12,000 feet most times and those observations from one trip seem about right for the rest plus I can confirm from having to drive several of the distances that there is full phone coverage a long the routes.
Re: GSM text messaging while flying (Score:5, Funny)
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1) Get an untraceable PAYG mobile
2) Load it onto a remote-controlled plane
3) Fly it around over central London at lunchtime
4) ???
5) Try to explain to Hastur and Ligur exactly how this constitutes
6) Profit!
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And I don't think guys like Crowley care about being traced...
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He said that the big problem was that it is very tricky for an airborne phone to decide what cell it's closest to, since it can see loads of them and they're all pretty much the same distance (the downward distance is now very large compared to the on-ground inter-cell distance). This means your phone keeps jumping between cells, which incurs quite a lot of overhead on the network (and if you had a plane
Re: GSM text messaging while flying (Score:4, Informative)
Re: GSM text messaging while flying (Score:5, Informative)
More likely you had too much signal. From altitude you tie up one RF channel on several dozen towers in range instead of running at reduced power on the closest tower. This blanket coverage of dozens of towers tying up a channel without the ability to hand your signal to a single tower and free up the frequency on other towers for use by others is why they don't permit phone use on aircraft. If the system is smart, it may have shut down your phone to clear the frequency as the towers noticed an even signal strength from one phone over dozens of towers. You simply did not get a tower assignment at altitude.
Re: GSM text messaging while flying (Score:4, Insightful)
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Re: GSM text messaging (Score:4, Funny)
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Re: GSM text messaging (Score:5, Informative)
At least this is my only partially-informed assumption (a long time ago I was a radio negineer, but I don't know about the actual implementation details of GSM.) But logically, allowing in-flight GSM phone calls is a bad idea because of the reasoning above. The system is designed on the assumption that calls will be made on the ground, therefore range-limited, and thus can only possibly be routed by one or two base stations, not hundreds.
Re: GSM text messaging (Score:5, Funny)
Not to be a sarcastic, literal-taking idiot, but I bet if I were, say, 0.5 AU high, my phone wouldn't work. Heck, I bet the lousy thing wouldn't even work from the moon's surface, especially if I was in a tunnel.
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I've experienced problems which I am pretty sure are related to hopping between towers -- not on an aircraft, but when hiking in the Smokey Mountains in North Carolina. We got up to the top and I was surprised to find that I had 4 or 5
Re: GSM text messaging (Score:4, Insightful)
On the flip side, the phone can't deal with dozens of control signals from dozens of towers on the same channel. Normal operation a phone sees a control channel from several towers nearby on several frequencies. These control channels get geographly re-used. At altitude it's the ability to see many towers on the same frequency at the same time scramples the signal to the phone and breaks the phone ability to lock on to a control signal. This is the sudden loss of signal bars seen on an airbone phone. Too many towers in view at close to the same signal strength and on the same channels as each other.
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The planes fuselage acts as a non-perfect faraday cage, so most of the signals get blocked, to compensate the mobile phones transmit at full power, which however isn't all that good for the planes electronic. If they have a GSM mini station on board the mobile phone will send with low power, since the signal isn't blocked by the fuselage anymore. It would of course also make the calls more stable, since there is a lot less probability for disconnects, GSM was
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Now not to say
Right, because we all know (Score:2)
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Re: GSM text messaging (Score:5, Interesting)
those poor /.'d fools! Put the pics on FLICKR!-n/t (Score:2)
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ACES (Score:4, Informative)
Regardless, what they've done is an outstanding achievement. The year before mine our school tried to take a picture up there (~100,000 feet) but it didn't work because the cold temperature changed the timing of some electronics, causing them to malfunction =/
I was in charge of the thermal stuff, and let me tell you, it's pretty hard to keep it warm but not so warm that the sun toasts it. And keep in mind the payload, as they call it, could only be 500 grams!
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I was in charge of the thermal stuff...
Hmmm. So you're saying it was your fault?
P4 would have warmed it. (Score:2)
or stop it. If the box is well insulated, then the real problem would more likely be TOO much heat that cant
be got ridden off because of the low presure in air. Paint the 'probe' white too btw to reflect the suns heat if its too hot
or black if its too cold.
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(Disclaimer: although I work in the same lab as the CUSpaceflight folks, I'm not a member of the team and am not an official spokesperson, etc, etc)
The guys now have a lot of interest from various agencies, organizations and university departments to get them to fly payloads to do exactly that sort of thi
Necessity is the mother of invention (Score:2)
In other news, Steve Balmer was today announced as the MS space program's launch mechanism of choice.
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They can't, it looks like they want to get payload with a rocket up to 100km. Which is nice and probally usefull for some tasks, but for satellites they would need quite a bit more altitude and of course speed, else gravity will simply catch them and the whole thing falls back to earth.
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To put something into a stable orbit, you must not only achieve height, but tangential velocity. A rocket that is capable of achieving the neccessary velocity (around 7000 m/s depending on how heavy the object is) will
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Steve Ballmer's throwing arm must be as big around as a sequoia to have pulled that off.
New Aproach? (Score:4, Informative)
Old Approaches (Score:2)
Really, if anything, the story is that someone is actually employing a good idea. That's where humans tend to fall down a bit. We've got all kinds of good ideas, but no one ever uses them. Like, this dud
Since 1949, actually... (Score:2)
According to Wikipedia's entry on James Van Allen [wikipedia.org] (who, you may recall, passed away just last month), the concept of the "Rockoon" was announced March 1, 1949 by Van Allen and his fellow researchers (some of them US Navy).
I'm sure Dr. Van Allen would be glad to see people continuing to follow in his (impressive) footsteps.
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Orbit (Score:2)
I'd contribute to a prize for that.
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To get there from 20 miles would still require a considerable rocket, though, and I'd be very surprised to see them pull that off for under US$2k. That additional 40 miles is still a considerable event in amateur rocketry, even with the wind essentially eliminated, and that's from a standing start.
And it's a very, very long way to
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(Disclaimer: although I work in the same lab as the CUSpaceflight folks, I'm not a member of the team and am not an official spokesperson, etc, etc)
They're not planning to get to orbit, although they are plann
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This sounds all very interesting ... Is there a project page on the net, or otherwise further reading?
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You keep using that word. I do not think it means what you think it means.
Specifically I think it means about 7.73 km/sec away from what you think it means. Going up is the easy part. The trick is staying there.
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Where's the fun in that? (Score:2)
"During his descent, he reached speeds up to 614 miles per hour"
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Unless of course you consider his pressure suit to be a "craft."
Lee
Are we sure... (Score:2, Funny)
Yes, but orbital? (Score:4, Insightful)
Re:Yes, but orbital? (Score:5, Informative)
Re:Yes, but orbital? (Score:4, Interesting)
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Meh. From that altitude, even a little weeny rocket can hit anywhere in the UK.
Try long metal cables. (Score:2)
So attach something like that to your rocket, get the power to 'push' yourself somehow using all those megawatts. Strong electro magnets?
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Raw RGB? (Score:2, Informative)
Yikes! (Score:2)
32 Kilometers = What? (Score:3, Informative)
You can see that weather balloons are in the 18-50 km range, which is what we expect, because that's what they're using, and they got to 32 km.
Uh, no... (Score:3, Funny)
So they're sending a high-end Dell laptop into space? It's been awhile since something blew up on the way into space.
That's a sounding rocket (Score:3, Informative)
That's a sounding rocket. In terms of performance, it seems comparable to the WAC Corporal [designation-systems.net] of 1944, or maybe the Aerobee [nasa.gov] of 1947.
Nothing wrong with building one cheaply, but it's not a step forward.
32 km, pretty nice (Score:2)
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Costs/Point (Score:3, Insightful)
Next time, manned flight (Score:2)
Sputnik anniversary? (Score:2)
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because launching the rocket is EFFECTIVE, compared to a balloon that will only reach about midway/three-fourths of the way in the atmosphere, only to fall back to the earth. the rocket has enough to push at a force that will allow it to get into orbit. not efficient, but it's the only way we get the job done.
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It can't. It falls straight back down again. There's a small matter of mach 25 horizontal speed to achieve before it's an orbit.
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One of them already built a working hydrogen fusor in his garage.
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Can you say http://en.wikipedia.org/wiki/Dirty_bomb [wikipedia.org] ?
Hmmm (Score:2, Funny)
Sorry.
Re:lunatics?! (Score:5, Informative)
The casing is made of a type of foam that is very good at absorbing impacts, and the whole thing doesn't weigh very much.
If it landed on you with the parachute open you'd just brush it off. If it landed on you without the parachute you'd get a bruised head but would be okay.
Our launches are insured with £5m public liability cover. Arranging this insurance was quite difficult though.
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Re:Precise landing? (Score:5, Informative)
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Well, with the alternative name being Ballet, Rockoon doesn't sound so bad!