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Origami Plane to Fly From the Int. Space Station
SK writes "The University of Tokyo and the Japan folded paper (origami) plane society hopes to fly a paper airplane from the International Space Station to Earth. The plane will be 30-40cm long and weigh about 30 grams. A University of Tokyo research group has successfully designed a special paper plane model that was able to withstand a Mach 7 high velocity stream for 10 seconds. The experimental plane was about one-fifth the size and withstood temperatures as high as 300C without burning up." Unfortunately for most of us reading this, the original source is all in japanese.
"Check out what I made!"
"Ha, that's sweet! You know what we should do with it?"
*Airlock Sounds*
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Japan wants to fly paper plane from International Space Station to earth:
http://mdn.mainichi.jp/national/news/20080118p2a00m0na025000c.html
I have excellent Karma and I am not afraid to Troll it.
uh, Fascinating!
8 centimeters in length experiment, the space shuttle heat-resistant form of folded paper airplane use by the process. Tokyo campus Ookashiwa (Kashiwa, Chiba Prefecture), a super high-speed wind tunnel tests of the high-speed stream of Mach 7 in the heat resistance and strength to find out.
When the space shuttle and other spacecraft will return to the speed of Mach 20, and the friction in the air and high temperatures for the heat-resistant surface is a special twist. Paper airplane is so light, slowing down from the thin air, landing in slow. Coming back without burnout might be.
Suzuki professor at Tokyo University (aerospace engineering) is a "message of peace from the space station to skip it. Land in the world where you do not know the fairy who could deliver" a dream said.
This is brilliant! The use is obvious. We need cheaper reentry vehicles. These vehicles would not be designed to bring back passengers, but there are times when you have 50 (harmless) samples and would like to get one of them to a lab earth-side.
First, for those who say they've never seen a paper airplane break 100MPH, that's at 1 atmosphere. Mach 7 is definitely not at 1 atmosphere.
Second, for those who say it would flip, try writing a stability proof sometime. do you know how to apply inverse kinematics? can you write an equation for the Jacobian of a human elbow joint?
Third, the first step is to try one small paper plane. It'll probably not work, and we'll have to try again. Eventually, we might get a working 8" plane. Some day, we might even have a meter long plane that can bring 3 ounces back to earth.
Imagine an astronaut who is sick, and we need to get some lab tests run. Sending a shuttle or Soyouz down is incredibly wasteful. OTOH, a paper airplane could be equipped with a tracking device (think 1-2oz GPS & transmitter) and a small sample case. We drop the plane, and it's got a 1-in-3 chance of getting the sample into the right hands, in a usable condition. So we drop 5 or 10 and hope for the best.
Think of the potential when we start building larger stations & craft in space. A line of bolts could shear off, and we might not have the ability to analyze it in space. We drop one on each of 5 paper planes, and get a good idea from 2 that we recover of what happened. Were the bolts defective? Was it a fatigue issue? Were they improperly installed?
Imagine a very low cost mission to a near Earth crossing object. Half a dozen paper planes could let us get a few ounces of samples on the cheap.
Andy
Fuck you, scissors and rock!
Now I know how the manual for my DVD player was translated.
Gamingmuseum.com: Give your 3D accelerator a rest.
As a rocket scientist, I'll take the reins here.
From the altitude the ISS is orbiting, there's no such thing as approaching the atmosphere "slowly". The ISS is traveling at about 17000 mph around the circumference of its circular orbit. In order to enter the atmosphere, a body in that orbit would have to slow down in order to enter an elliptical orbit which intersects the atmosphere. This requires a velocity change (delta v) of about 200-250 mph. Even with that change, you're still traveling at 16,750 mph, so that when you finally do hit atmosphere, the friction from the air will be very high, even if the air is thin. As the friction slows you down, you drop farther into the atmosphere, where the air is thicker and there is more friction. These two changes (air pressure and velocity change) work together to reach a point of maximum heating, and then taper off again as you reach subsonic speeds. The steeper the dive, the faster you reach thicker air, and the higher the max heating point will be.
Let's say for argument's sake that you wanted to drop straight down from where the ISS is orbiting, with no horizontal velocity. (That would require an instantaneous delta v of the whole 17000 mph, which is nigh impossible, but we'll assume we can for our thought experiment.) Since the ISS is orbiting at an altitude of about 225 miles, and the atmosphere is generally considered to start at the 62 mile mark, that's still 163 miles of vacuum free fall to contend with. Leaving out the square-of-the-distance effects of gravity fall off (which are close to negligible at these distances), we get a fall time of sqrt((163 miles)/(32 feet per second squared)) = 164 seconds. That gives us a velocity of (32 feet per second squared)*(164 seconds) = 5248 feet per second, or 3578 mph at the moment we hit the upper fringes of the atmosphere. The heating will certainly be less than the standard deorbit, but it is still a decent force to be reckoned with. Any angle larger than the vertical will require a smaller delta v but will result in a higher entry velocity and higher heating.
Now you might be thinking to yourself, "but AeroIllini! You totally contradicted yourself there!" I did. Except that as you vary the angle of entry from shallow to vertical, the graph of max heating reaches a peak and then falls off again. So for a very shallow entry, your heating will be lower than a steeper entry, but going even steeper the heating will taper off again until you reach vertical entry, which will have the lowest heating of all. Vertical entry also has the highest delta v requirement of all, and a shallow entry has the least delta v required.
I hope this answers your question.
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Don't underestimate the power of pure curiosity. Maybe launching paper airplanes from a space station isn't directly going to contribute to anything great like curing cancer, but when that great thing does happen, I'm certain that the big leaps are going to be made by people that just followed their curiosity, instead of worrying about the significance of what they're doing.
As an example, Richard Feynman had sort of a breakdown early in his career. His inspiration had run out, everybody was waiting for the genius to do something brilliant, and he was feeling miserable. Then he decided that he wasn't going to care about people's expectations, about what kind of research was respectable, he was just going to follow up on the little things that interested him. He sat in a cafeteria, looked at a spinning plate (I don't remember the details, there was a spinning plate somehow) and he decided he would try to figure out the forces that made that plate spin like that. He did figure it out, proudly showed it to some senior, who said 'great, but what's the relevance'. There wasn't any, he'd just followed his nose, and solved a problem. Later that little solution turned into to the research that earned him a Nobel prize and became the most accurate scientific theory to date (or second most accurate, I'm no expert).
The point is that many scientists don't work well on something that is prescribed in any way. They need absolute freedom to just do stuff that interests them. If they really have to they can work on things that are more immediately relevant, but not with passion, and it'll never be as great as the stuff they do when just follow their instinct. And these scientists tend to be the ones that come up with the great breakthroughs.
So if these guys want to send up 30 grams with the next shuttle, and take up three minutes of the astronauts' time, I'm fine with that. It's important in a subtle way. It's also very cool.
Here's a human translation, if it helps.
In order to make a paper airplane that can fall back to Earth from a space station, the Japan Origami Paper Airplane Group and Tokyo University have been brought together. Using the University's wind tunnel, testing was performed on the 17th.
In the experiment an 8 cm long paper airplane, folded into the shape of the space shuttle, was made of material that had been treated for heat resistance. It was tested for heat resistance and strength in a Mach 7 airflow generated by the ultra high speed wind tunnel located at Todai's Kashiwa Campus (Kashiwa City, Chiba Prefecture).
Space vehicles such as the Space Shuttle can reach speeds of Mach 20 on reentry and due to the high temperatures caused friction with the atomosphere, their surfaces require special heat resistance devices. Because of the low weight of the paper airplane, it will begin deceleration from where the atmosphere is thin and be able to land slowly. It is said that it may be able to return to Earth without burning up.
Shinji Suzuki, professor of aerospace engineering at Tokyo University, shared his dream. "I want to fly it from the Space Station with a message of peace. I don't know where in the world it will land, but hopefully the person who finds it report it."
Use of the words "good", "bad" or "evil" is almost invariably the result of oversimplification.