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No One Wins NASA Space Elevator Contest
volts writes "According to New Scientist no one was able to grab the two $50,000 top prizes in the recent NASA 'Beam Power Challenge'. The biggest limiting factor seemed to be that no team was able to meet the speed requirement, although a group from the University of Saskatchewan in Canada set the height record at 12 meters. Not quite geosynchronous..."
The biggest limiting factor seemed to be that NASA didn't offer enough money to get any remotely reasonable solution to the problem. Fifty thousand dollars is chump change to the kind of money needed to develop any of this technology.
I think it has more of a chance of working than you. How's the view from the family basement, junior? The thing that people fail to realize is that even if a project never reaches its goal, it has the potential to spawn innovation that can be applied to other problems. There is a quite a list of things that are NASA castoffs that are used in everyday life.
You are in a maze of little twisting passages, all different.
"Quick guys, we gotta find a way to spin the Earth up really fast so we can call our elevator geosyncronous. There's $50,000 at stake, people!"
--- Journals are boring; Go to my web page instead
They should set a slightly lower speed limit. This would encourage more people to work on the problem.
The minimum speed was 1 meter/s = 3.6km/h = 2.2369 miles/h. I can walk faster than that.
Geosynch is 35,786 km above sealeve according to wiki. At 3.6 km/h it would take over a year to get up to geosynch. They really should increase the minimum speed.
Fly me to the moon Let me sing among those stars Let me see what spring is like On jupiter and mars
Not quite geosynchronous...
Oh, it's quite geosynchronous (i.e. above the same point on the Earth surface). It's just not in orbit.
So close and yet so far from the world's perfect ID number
Maybe if we stacked them...
The problem was apparently that the spotlight they were using had too diffuse of a beam. Next year, when the teams provide their own beaming systems, it might turn out better.
Ewige Blumenkraft.
Go back to steam engines, stirling engines? If your power source is light, why bother with electrical engines? Use some liquid gas as fuel in a tank, use the projected light as a heat source, let the gas heat up in a combustion chamber (a piston?) and drive the whole thing up as a locomotive :)
You can't handle the truth.
Wonderful idea! Now all we have to do is build a skyscraper that's 22,240 miles tall, and we can use these babies to get into orbit.
Power source this time was limited to a single high-power searchlight... faster requires a whole lot more power, and it simply wasn't going to be available in time.
Most teams didn't have the chance to test at their own facility with their own searchlight, nor at the competition site. If you can't really test, you shouldn't assume highly efficient operations...
The tether in use wasn't that tall, and accellerating and decellerating a whole lot within the available vertical distance was a nonstarter.
This was a introduction to parts of the problem set, not a realistic attempt to engineer production grade tether climbers. Everyone involved knows that...
Excellent point! In fact, most Space Elevator proponents seem to miss the fact that the energy for the elevator isn't free. You still have to expend at least the minimum amount of energy required to move an object into LEO. The physics of the situation say there are no shortcuts.
What you DO gain is:
a) Slower ascent
b) Only minor (if not inconseqential) losses from air friction
c) Ability to expend the power over a long period of time vs. in a huge controlled explosion
d) A workable descent mode that doesn't require that the hull handle extremes
I'm all for the space elevator idea. However, a lot of people need to understand that this is NOT existing technology. While it's very much possible for the necessary breakthroughs to be completed in the next few decades, dropping everything and working on a Space Elevator would only mean that we'd lose space access for a very long time. That is why NASA is pursuing the CEV and not the Space Elevator as the next major launch vehicle.
Javascript + Nintendo DSi = DSiCade
Didn't they do this on Junkyard Wars with a jet ski engine, duct tape, and a couple pieces of PCV?
When will Windows be ready for the desktop?
You've missed a major point to the space elevator scenario--controlled descent.
In a standard descent, all the excess kinetic energy is wasted as heat. In a space-elevator scenario, you can use the energy of the descending cars to assist in powering the ascending cars. Net overall energy expenditure required is just enough to start the system and overcome the inevitable inefficiencies. Your average energy-per-car can be much lower than the rocket scenario.
... was disqualified for "inappropriate" elevator music... Under testing situations, all of our patients (read: monkeys, elderly, humans, and fish) were driven insane, then promptly driven sane, then insane, then sane, and so forth during the 62.5 mile elevator ride finished. After the tenth go around we decided the cost to hosing out the compartment filled with bile, blood, and bits of hair were not worth the cash prize. So it goes. Additionally, the PSP battery life wasn't sufficient to stave off elevator-maddness either. http://trs.nis.nasa.gov/archive/00000377/01/tm1085 37.pdf
The minimum speed was 1 meter/s = 3.6km/h = 2.2369 miles/h. I can walk faster than that
Not straight up, you can't.
Geosynch is 35,786 km above sealeve according to wiki. At 3.6 km/h it would take over a year to get up to geosynch
True, but as gravity decreases, you accelerate faster per unit energy. I can't be arsed to actually do any math, but 1m/s at 1G is going to translate into significantly higher velocity the further out you go. Besides which, if you want to use the elevator primarily for moving materiel rather than personnel, a one-year turnaround might not be too bad; throughput is potentially more important than lag.
Even for personnel, that's on the order of time it took to sail from Europe to America via wind power, and people did that.
Reality has a conservative bias: it conserves mass, energy, momentum...
Why would I try to win this year when the prize money doubles for next year? "Next year, both contests will be repeated but the top prizes will rise to $100,000." Let me guess... the year after that the prize money goes to $250k? Sounds backward to me...
I'm not clever enough for a sig...
Totally unnecessary. If the capsule goes up at 1m/s, it will run 1km in 1000 seconds and 200km in 200,000 seconds, which is about 55.5 hours. At that distance the speed of the capsule can be raised by other means.
You can't handle the truth.
Great minds think alike; fools seldom differ.
\i{I have seen suggestions that ~46,000 mph or 13 miles/sec would get you into orbit.}
Orbital velocity for LEO is about 18000 mph, or roughly 5 miles/sec.
Earth Escape Velocity is about 25000mph, or roughly 7 miles/sec.
46000mph is so far beyond what is needed for orbit, it's ridiculous.
General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
I am quite annoyed that NASA would even risk $50,000 of mine and other tax payer's money on such a preposterous game.
But this is what government is for. In a republic such as ours, the presumption is that a service or commodity for which any dolt can see the need is going to be supplied by the private market. Why not? You can get rich doing so (cf. Gates, Bill). On the other hand, there are a few things that people as individuals or even large firms can't provide (such as national security) or won't provide because it isn't obvious they're going to work -- such as space elevators.
Enter the government. It's government's job to finance "preposterous flights of fancy," because private industry (very sensibly) won't. Most of that blue-sky stuff turns out to be nonsense, naturally, But some of it doesn't. Some of it, in fact, turns out to be ideas so ingenious that they seemed like pure folly to ordinary folks -- that would be you and me and nearly all other voters -- when they were originally proposed. And, of course, these are the clever ideas that will sustain our ability, a hundred years from now, to compete internationally on the basis of being smarter than anyone else, not working for less. I don't know about you, but I prefer to work in a high-wage, low-volume economy than a low-wage, high-volume economy.
Now, there's no doubt a proper amount of bread that government should cast on the waters. We could argue about that. But not in this case. I don't see how anyone who accepts the role of government in financing very basic research could figure that $50,000 out of a $1.8 trillion Federal Budget is wildly over the top.