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NASA Tests New Moon Engine
Iddo Genuth writes "Pratt & Whitney Rocketdyne of West Palm Beach, Florida has successfully completed the third round of its Common Extensible Cryogenic Engine (CECE) testing for the National Aeronautics and Space Administration (NASA). CECE is a new deep throttling engine designed to reduce thrust and allow a spacecraft to land gently on the moon, Mars, or some other non-terrestrial surface."
NASA is also set to launch a new satellite on Tuesday — the Orbital Carbon Observatory — that will monitor the level of carbon dioxide in the atmosphere. On the research front, NASA has announced this year's Centennial Challenges. $2 million in prizes are available for a major breakthrough in tether strength (one of the major obstacles for developing a space elevator), and another $2 million is being offered to competitors who are able to beam power to a device climbing a cable at a height of up to one kilometer.
Wouldn't it just make more sense to have solar panels in orbit and transmit the power along the space elevator? If I remember correctly, this is what Kim Stanley Robinson envisioned with the space elevator in his science fiction novel Red Mars . Being able to bring power down would be a nice bonus for a tool to get up to orbit easily.
Took me a second look to realize that I'd read it wrong the first time...
I have always wondered why we can't have something like a nuclear battery on board the elevator. Is it their weight/volume that make them impractical?
Recent articles like this one http://www.sciencedaily.com/releases/2005/05/050514205902.htm suggest such technology is in development. And they nuclear subs already have their own power supply.
Hmm...Ok some thoughts....
We have worked on star wars programs....Is it not possible to build a super precise Laser based weapon to target the terrorists no matter where they are? A small pulse of Laser in the head of terrorist and he is gone. A good telescope with good precision laser should be able to take care of any terrorist without launching any drone attacks. I understand it may have its own technical challenges, but US certainly can do it. Isn't it?
hilarious
Why then try to do anything? Artificial light, nuclear power, cars, organ transplants? They were all impractical at first.
If this was a rhetorical question, then I lost and bit, but otherwise, with this attitude, not much would have ever been invented or tried.
The space elevator might be the best and most efficient way to get large amounts of material into space, unless we invent anti-gravity.
..........FULL STOP.
I wonder how much testing they did for Apollo mission.
This looks way better http://en.wikipedia.org/wiki/Space_fountain
There are several reasons: 1) Gravity on Earth is high relative to these "non-terrestrial" surfaces. The CECE engine might not have the thrust/weight ratio to land on Earth. 2) Earth also has a thick atmosphere. That greatly reduces the throttling capability and you need to come up with a gimmick like thrust augmented nozzles to maintain nozzle efficiency (and ISP) in atmosphere. 3) There are other means of landing on Earth (eg, parachutes).
The rest of the world may not appreciate such a weapon very much, as it probably wouldn't be hard to point it away from the terrorists and at, say, China or Russia.
That is probably the most likely reason we don't have a real orbital weapon yet.
The space elevator is more than likely just a materials engineering problem, while anti-gravity would require spectacular new scientific theories.
So yes, but still I don't think much is impossible, much of what we take for granted now would have been impossible 500 years ago.
..........FULL STOP.
See... http://www.luft46.com/misc/sanger.html Note the engine details. There is a jet engine fuelled by liquid oxygen and hydrogen, piped through the jet bell, so it gets cooled and the fuel gets vapourized. Neat, eh? Clever guys, those Germans.
My question is, though, how do you stay off the terrorist/person of interest/'enemy combatant'/etc list and still have some reasonable freedoms left? And how thick will the tinfoil need to be to keep that 15 MW laser from toasting your brains?
Understanding the scope of the problem is the first step on the path to true panic.
If you were Australian, they'd take you to the moon and back for just being their baby.
In times of distress, sit back, get a cup of tea and mumble... "bugger!"
The terrorist will work out the orbit with a telescope costing a couple of hundred dollars, or even with the naked eye. Then he will know when to stay indoors.
And no, geostationary is too far out of sniping.
# cat
Damn, my RAM is full of llamas.
The Orbital Carbon Observatory doesn't measure carbon dioxide, it measures spectral absorption of sunlight reflecting off the surface of the earth.
The really cool thing about this is that the analysis is so sensitive to factors and assumptions that the results can be anything we want them to be.
I'm a Programmer. That's one level above Software Engineer and one level below Engineer.
The mechanical requirements for a gondola ride have been worked out already (e.g., http://en.wikipedia.org/wiki/Skyway_(Disney)). Turning the cable into a loop is a clever idea that provides a route down as well as up, for instance.
As somebody else said, even if such a technology never proves practical on Earth, it certainly might be on other planets. Mars would be easier, for instance - less gravity, similar orbital period, thinner atmosphere.
The issue with building a geosynchronous elevator on the Moon is that it is tidally locked with the Earth (more or less). In effect, the Earth itself is in selenosynchronous orbit, so the cable would reach all the way back to Earth. It is even more unlikely that such a long cable could be built, but it wouldn't have to point toward the Earth, of course. There are many other moons in our solar system (http://www.windows.ucar.edu/tour/link=/our_solar_system/moons_table.html) and others appear better suited for an elevator. The Galilean moons of Jupiter, for instance, or Titan around Saturn, all have rotational periods shorter than our Moon's, some just a few days.
Or around asteroids (think mining), or untethered cable structures in orbit about any of these. There are good reasons to pursue the technology even if the original concept proves unworkable when the engineering is looked at in detail. Simply failing to pursue new ideas is the only way to guarantee they'll never be realized.