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NASA Tests New Moon Engine

Soulskill posted more than 5 years ago | from the rocket-fuel-green-cheese-hybrid dept.

NASA 75

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.

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Space elevator power? (4, Insightful)

CRCulver (715279) | more than 5 years ago | (#26941287)

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 [amazon.com] . Being able to bring power down would be a nice bonus for a tool to get up to orbit easily.

Re:Space elevator power? (2, Informative)

John Hasler (414242) | more than 5 years ago | (#26941407)

It's the same problem whether you are sending the power for the climber up from below or down from above.

Nuclear Batteries (1)

mrops (927562) | more than 5 years ago | (#26941605)

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 [sciencedaily.com] suggest such technology is in development. And they nuclear subs already have their own power supply.

Re:Nuclear Batteries (1)

tcolberg (998885) | more than 5 years ago | (#26941743)

Depending on whether transmission along the cable is possible, a power source internal to the elevator car may be necessary. Though, it would seem that an internal power source is very undesirable. If cargo capacity and reduction of wear on the cable are important parameters for the elevator, then reducing on board weight for the car would indicate that an important goal is to try to find a method of powering the car externally.

Re:Nuclear Batteries (1)

Fanro (130986) | more than 5 years ago | (#26942111)

i would guess that the power output is too small to overcome gravity
nuclear batteries on probes have a very small output, barely enough for the onboard electronics.
Nuclear subs on the other hand are immense and heavy.
And nuclear subs have a much better temperature gradient to work with, since they have an infinite supply of water for cooling.

Re:Nuclear Batteries (1)

Clay Pigeon -TPF-VS- (624050) | more than 5 years ago | (#26943529)

I think you're confusing a radioisotope battery with a nuclear reactor.

Re:Nuclear Batteries (1)

default luser (529332) | more than 4 years ago | (#26959007)

No, he's not, he's bringing-up both types in the same reply.

He casts-off RTGs immediately because their power output sucks, and then he dismisses naval fission reactors [fas.org] because (1) they're huge and (2) you need a way to remove the waste heat.

Unfortunately, efficiently creating mechanical/electrical energy from heat requires a large temperature differential. Once you've used-up all the energy you can and the temperature drops, the remaining energy is waste heat, and must be removed from the system. Naval reactors work well in this situation: they have an unlimited supply of cool water to remove waste heat. But on a cable in space, the heat has nowhere to go, except perhaps along the cable (who knows if cable material would make a good heatsink).

Re:Nuclear Batteries (1)

badkarmadayaccount (1346167) | more than 4 years ago | (#26961025)

Carbon nanotubes are, and naval reactors are, like, the size of a dustbin. Even shielding isn't that big. Besides, you'll need it anyway, you're in space, remember?

Re:Nuclear Batteries (1)

default luser (529332) | more than 4 years ago | (#26961841)

Carbon nanotubes are,

Granted.

and naval reactors are, like, the size of a dustbin.

Did you even READ the link I posted? The smallest reactor core on that page has a volume over 32,000 cubic feet, and weighs 1130 tons. 1130 TONS. That's one gigantic dustbin.

And keep in mind, these are some of the world's most advanced reactor designs. While the civilian nuclear power industry has largely langushed in the last 30 years, the military has been running a tight ship. You really can't make them any smaller without sacrificing power output, and believe me, a space elevator is going to require as much power as a submarine to move it's mass.

Even shielding isn't that big. Besides, you'll need it anyway, you're in space, remember?

Tell that to the countless NIMBY whiners. You don't think they'll come calling when you put a giant fission reactor above every home on the continent? You don't think they'll bitch until the whole thing is wrapped in radiation and heat shielding, just like RTGs?

And HELL NO, that shielding isn't tiny - it's the reason those naval reactor compartments on the linked page were so large.

You need the shielding no matter what you do: if you plan on lifting people into space using these things, you need shielding. But let's say you're not lifting people into space, just bulk: you STILL need shielding because of the detrimental effects of Radiation Damage [wikipedia.org] . You can harden electronics to a degree, but it's no replacement for radiation shielding. In addition, you can cause premature fatigue failure in matrials by exposing them to high levels of radiation - NOT something I'd want to expose the cable to.

Re:Space elevator power? (1)

khallow (566160) | more than 5 years ago | (#26941451)

Wouldn't it just make more sense to have solar panels in orbit and transmit the power along the space elevator?

How do you know it makes more sense? How are we going to transmit the power along the tether? My point here is that we don't know enough to make such a determination.

Re:Space elevator power? (1)

TropicalCoder (898500) | more than 5 years ago | (#26941821)

How are we going to transmit the power along the tether?

...was reading just the other day about this company that proposes to put up solar panels in orbit and beam the energy down via microwaves. Now there was an image of an antenna farm on the earth below, implying you need a large collector area for this to work. However, the energy could be tight-beamed via a maser to a small antenna, perhaps - a small, light antenna mounted on the climber.

Re:Space elevator power? (1)

geckipede (1261408) | more than 5 years ago | (#26942279)

Microwaves aren't easily aimed. A maser is a very different type of device to an optical laser, the only similarity is that they both give coherent radiation. Lenses for microwaves aren't practical and the emitters aren't inherently directional as lasers are. The reason why the space power satellite would have needed such a giant field of rectennas is that at >100km range, getting more than 50% of the beamed power into a patch of less than a kilometre is next to impossible.

Re:Space elevator power? (1)

Joce640k (829181) | more than 5 years ago | (#26941483)

Wouldn't it make more sense to just not bother. For sheer impracticality, space elevator is one of the silliest ideas ever.

Re:Space elevator power? (1)

stevelinton (4044) | more than 5 years ago | (#26941555)

Why? There are some problems to overcome, sure, but I don't see obvious show-stoppers.

Re:Space elevator power? (0)

Anonymous Coward | more than 5 years ago | (#26941747)

> but I don't see obvious show-stoppers

Sorry, but it's quite obvious that you are neither a physicist, nor a material scientist, therefore your opinion is irrelevant.

Re:Space elevator power? (2, Insightful)

Kleen13 (1006327) | more than 5 years ago | (#26942023)

And you are? What if he owned a hardware store? Would that count?

Re:Space elevator power? (1)

badkarmadayaccount (1346167) | more than 4 years ago | (#26961047)

No.

Re:Space elevator power? (1)

nmg196 (184961) | more than 5 years ago | (#26941985)

Apart from the really obvious one of needing an almost infinitely strong piece of cable? So far, carbon nanotubes (the main contender to make a very strong cable) are limited to being only a few millimeters long. Not quite the several kilometers they require for a space elevator.

Re:Space elevator power? (1)

davidbofinger (703269) | more than 5 years ago | (#26952467)

The show stopper is that every sub-geosynchronous satellite would sooner or later collide with the elevator. A space elevator would be nice, but lower-orbit satellites are way more important.

Re:Space elevator power? (1)

Bragador (1036480) | more than 5 years ago | (#26941651)

Yes, because it is completely sane to say "Ok guys, as of 2100, we can say the space elevator is impossible to make. All that research only gave us elevators of 1km high. This is SO useless".

Re:Space elevator power? (1, Insightful)

Anonymous Coward | more than 5 years ago | (#26941691)

i call bs.
for sheer impracticality, chemical rockets are one of the silliest ideas ever. and look, they still managed to catch on.

Re:Space elevator power? (3, Informative)

TropicalCoder (898500) | more than 5 years ago | (#26944389)

I think one of the silliest notions I ever heard is the idea that we could propel a carriage without a horse, by using explosions from a highly explosive liquid substance. Obviously the first time they try this they are just going to blow the carriage sky heigh. The simple reason this will never work is that they forgot that a carriage has a thing called inertia, and it will quickly buckle under the force of the explosions rather than be propelled down the lane. Even if it could withstand the force of the explosions, could you imagine what kind of jerky ride you would have?

ust not bother???? (2, Insightful)

spineboy (22918) | more than 5 years ago | (#26941779)

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.

Re:ust not bother???? (0)

pmarini (989354) | more than 5 years ago | (#26942551)

then why go for the space elevator when there is a chance to discover/invent antigravity first ?

or are there different "degrees" of impossibility/impracticality, in your opinion ?

Re:just not bother???? (1)

spineboy (22918) | more than 5 years ago | (#26942665)

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.

Re:Space elevator power? (3, Insightful)

khallow (566160) | more than 5 years ago | (#26941859)

Why should it make more sense to not bother? Even if a space tether from Earth proves to be too difficult to bother with this century, we currently have the materials to make less ambitious tether strutures in orbit or a space elevator on the Moon.

Re:Space elevator power? (1)

doug141 (863552) | more than 5 years ago | (#26944651)

Doesn't the moon's slow rotation prohibit a space elevator?

Re:Space elevator power? (2, Informative)

camperdave (969942) | more than 5 years ago | (#26945757)

Doesn't the moon's slow rotation prohibit a space elevator?

Yes and no. Yes, by itself the moon's slow rotation would call for a really long tether (to match the 27.3 day rotational period, and the counterweight would be too strongly influenced by Earth's gravity. I haven't done the calculations, but it wouldn't surprise me if the tether would have to pass through the Earth itself.

However, there is another space elevator design that will work. Between the Earth and the Moon lies the first Lagrange point of the Earth-Moon system (EML1). It is essentially the point where the gravitational pull from the Earth matches the gravitational pull of the Moon. Anything on the Earthward side of the EML1 gets pulled to the Earth, and anything on the Moonward side of EML1 gets pulled to the Moon. So, basically what you do is hang the counterweight on the Earthward side of EML1, and run the tether to the Moon. The counterweight is going to want to fall to Earth, but it will not be able to because it is tethered to the Moon.

Apparently we have sufficiently strong materials right now to be able to create such a tether. There are still engineering difficulties (such as getting a 56,000+ km length of kevlar rope strung out from the moon to the counterweight) but a lunar tether lies within our current technological capabilites

Re:Space elevator power? (1)

drinkypoo (153816) | more than 5 years ago | (#26951169)

Apparently we have sufficiently strong materials right now to be able to create such a tether. There are still engineering difficulties (such as getting a 56,000+ km length of kevlar rope strung out from the moon to the counterweight) but a lunar tether lies within our current technological capabilites

The problem is that we don't actually need a lunar tether until we have one attached to Earth.

I would think that at some relatively low altitude it becomes more efficient to beam the power down just because you don't have to go through so much atmosphere.

Re:Space elevator power? (1)

camperdave (969942) | more than 5 years ago | (#26954087)

We don't need a tether on the moon at all. There's no atmosphere, so a horizontal magnetic rail system will do just fine. It would probably be a lot cheaper to set up.

. . . and what about the Space Yo-yo? (0)

PolygamousRanchKid (1290638) | more than 5 years ago | (#26942227)

For sheer impracticality, space elevator is one of the silliest ideas ever.

The Big Orbital Hand In The Sky (BOHITS) drops the Space Yo-yo and it spins as the nanotube tether unravels, since the other end of the tether is attached to the Big Middle Finger In The Sky. When it is just a few feet above the Earth, at the end of the tether, the clutch pulls away from the axle, and it spins, while the ground crew load up the non-spinning cargo core. Then the Big Middle Finger In The Sky jerks the tether, causing the clutch to grab the axle again, and the spinning of the Space Yo-yo climbs up into space again, rewinding the tether for the next trip.

If you take a look at Wikipedia's Yo-yo page (http://en.wikipedia.org/wiki/Yoyo), you will discover, that Yo-yos are a proven and tested technology since 1000 B.C. The Space Yo-yo would simply need to address a few engineering scaling issues.

Re:Space elevator power? (1)

MMC Monster (602931) | more than 5 years ago | (#26942465)

No. You're probably thinking of a space fountain.

Re:Space elevator power? (0)

Anonymous Coward | more than 5 years ago | (#26943645)

âoeThis âtelephoneâ(TM) has too many shortcomings to be seriously considered as a means of communication. The device is inherently of no value to us.â
â" Western Union, internal memo, 1876

âoeI think there is a world market for maybe five computers.â
â" Thomas Watson, chairman of IBM, 1943

And coming soon to a reality near you:
âoeWouldn't it make more sense to just not bother. For sheer impracticality, space elevator is one of the silliest ideas ever.â
- Joce640k, Slashdot member, 2009

Re:Space elevator power? (0)

Anonymous Coward | more than 5 years ago | (#26941559)

Why is that helpful? The Earth's atmosphere doesn't reduce the intensity of sunlight that much that we need to put solar panels in orbit. Why not just use solar panels at its base. Or better yet, just plug it into the grid and let the market figure the best way to power it (coal, nuclear, hydro, etc.).

Re:Space elevator power? (1)

0123456 (636235) | more than 5 years ago | (#26941667)

The Earth's atmosphere doesn't reduce the intensity of sunlight that much that we need to put solar panels in orbit.

Solar power stations in orbit don't require as many resources as the same stations on the ground (very large mirrors can be thin and light in microgravity, etc) and produce their full power output nearly 100% of the time, tracking the sun 24/7 and only rarely going into the Earth's shadow. They also don't take up a huge amount of space on the ground which could be used for other things, like growing crops.

That's not to say that they would be cost-effective, but there are good reasons for preferring space-based solar power if the price is right. One obvious downside is that any wireless power downlink powerful enough to not require large amounts of space on the ground would also make quite an effective weapon.

Re:Space elevator power? (1)

KibibyteBrain (1455987) | more than 5 years ago | (#26941665)

As someone who has worked in high power engineering, I will note that is easier said than done. Its really hard to send power a long distance efficiently even when you have lots of transformer stations and such along the way, and with the benefits of the ground plane and other factors you get in land based transmission systems. I just don't think it would be practical to send that much electrical power 1 km with modern affordable technology in a straight shot, even on Earth.

Re:Space elevator power? (1)

spineboy (22918) | more than 5 years ago | (#26941829)

would be cool if somehow a superconductor transmission line could be incorporated into the space elevator (weight issues a prob). Or have it conducted on the surface (didn't NASA look at power generation from a tethered cable?) of the elevator cable. I'm not a EE so please forgive any ignorance.

Re:Space elevator power? (1)

YrWrstNtmr (564987) | more than 5 years ago | (#26941837)

Wouldn't it just make more sense to have solar panels in orbit and transmit the power along the space elevator?

Maybe. Build a space elevator and try it.

Re:Space elevator power? (0)

Anonymous Coward | more than 5 years ago | (#26941909)

Wouldn't it make more sense to connect to the existing terrestrial electric supply (at the base) and transmit up to the climber?

Re:Space elevator power? (0)

Anonymous Coward | more than 5 years ago | (#26942245)

And what happens when the panels start falling on earth like meteors threating the cities?

Re:Space elevator power? (1)

pmarini (989354) | more than 5 years ago | (#26942509)

talking of space elevators (slight offtopic, but still - funnily - related to the subject), couldn't we just use a counter-weight like a small asteroid or a roaming satellite to "lift" the elevator's cabin, like in traditional ones ?

Re:Space elevator power? (1)

Hucko (998827) | more than 5 years ago | (#26952581)

Sounds good, though you have this problem of the original elevator is (currently well outside) at the limits of material strength over such a long distance --- AFAIK the weight to strength ratio limits the size of our current buildings to only a little larger than the Kuala Lumpur building as compared to the distance to build an effective space elevator. Our buildings do rely on compressive strength rather than tension that a space elevator type buildings would use.

If you were to then have a cable with in a cable (your counterweight attached to the car) you would be adding to the weight of the main structure without adding any strength. * hand wave * Now you have over come that problem you wish to drop the car back to earth. You have to once again pull the car's counter weight towards earth, straining yet again the main structural cable.

I'm just a taxi driver and I could be discombobulating the terms too, but I think if you were talking to a material scientist, they would just laugh at you. On a big picture scale your proposal sounds great, but if we could make ONE cable that could go the distance, there would be many, many happy people.

Re:Space elevator power? (2, Interesting)

ThreeGigs (239452) | more than 5 years ago | (#26943181)

Actually, it makes the most sense (to me) not to use a powered 'climber' at all.

If the space elevator is ever deployed, instead of dropping a single tether down to Earth, they should drop a LOOP. Run the bottom of the loop around a pulley on Earth, and the top through a pulley on the counterweight in space. Add a motor to the pulley on Earth and you've got one half constantly going up, and the other half constantly going down.

All a 'climber' would then have to do is clamp onto the cable and allow itself to be pulled up, and unclamp at the appropriate time in space. So... no need for motors on the 'climber', no need for an energy receiver on the climber, no need for beam generators anywhere. Essentially turning the "Space Elevator" into the "Space Ski Lift".

The only engineering challenge I can think of would be preventing the up-going side from touching, or coming too near the down-going side. Potentially solved with two pulleys each on the ground and in space, each pair a kilometer or more apart so the 'tether' goes down, across, and then back up.

Re:Space elevator power? (1)

0WaitState (231806) | more than 5 years ago | (#26944463)

Well, there is the engineering challenge of making the elevator "cable" material sufficiently flexible that it can run through a pulley. A better approach would be to form the "cable" into a giant circle, and rotate the circle like a giant ferris wheel. Sounds silly, but if we're going to postulate a 100km load-bearing cable elevator, a 314km cable circle is equally feasible.

Re:Space elevator power? (1)

ThreeGigs (239452) | more than 5 years ago | (#26949801)

My idea of a pulley was something about 50 to 100 meters in diameter, much like a ferris wheel. It had less to do with flexibility though, and more to do with reducing wear and tear on the 'tether loop', preferrably bending it through a large radius, and exposing it to a large surface area for traction to drive it.

Re:Space elevator power? (1)

DerekLyons (302214) | more than 5 years ago | (#26947285)

The only engineering challenge I can think of would be preventing the up-going side from touching, or coming too near the down-going side. Potentially solved with two pulleys each on the ground and in space, each pair a kilometer or more apart so the 'tether' goes down, across, and then back up.

You missed:

  1. The shock loads of clamping and unclamping the 'climber' on both the cable and the climber.
  2. The vibrations caused by #1.
  3. Decelerating the 'climber' when it unclamps.
  4. Seriously increasing the difficulty because now you have the support structure, the lift wires, and all the structure needs to prevent vibrations from building up in the wire.

There's probably more, but that's all I could think of in ten seconds with my head fogged from a serious cold.

Space gondola (1)

rlseaman (1420667) | more than 5 years ago | (#26948505)

The mechanical requirements for a gondola ride have been worked out already (e.g., http://en.wikipedia.org/wiki/Skyway_(Disney) [wikipedia.org] ). 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 [ucar.edu] ) 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.

Re:Space gondola (1)

rlseaman (1420667) | more than 5 years ago | (#26948843)

Checking my math - it's hooey, of course. A lunar synchronous orbit is only a little more than twice the radius of a geosynchronous orbit. If we can build a cable 42,000 km long, we can build one 88,000 km in a lower gravity field and moving slower. Of course, if two guys can fly into lunar orbit using nothing but a single stage LEM, it isn't obvious we need a space elevator on the Moon.

The numbers for Mars might be the right trade-off. A synchronous orbit on Mars has less than half the radius as on Earth. Surface gravity is also under half, but not so low that reaching orbit is otherwise trivial. The atmosphere is down around 1% of Earth's. Of course, there is the little issue of Phobos, orbiting at lower than synchronous altitude...

Re:Space gondola (1)

ThreeGigs (239452) | more than 5 years ago | (#26950043)

It's not just about the route down, or the method of supplying potential energy to the payload. It's also about redundancy. If a tether breaks, you're out one counterweight and a lot of tether.

If a looped tether breaks, you simply put the brakes on at all four pulleys and you've still got a plain single tether. Send one bot up and one bot down the tether with the other 'half' of the tether looped over them, they clamp hard to the ends of the tether when reached, attach themselves together, and the looped tether is then spun until the break is at ground level and can be repaired more permanently.

It'd save a lot of downtime in the event of a failure or accident and save a rocket with a replacement tether and counterweight.

The only thing I'm unsure of is if Coriolis forces would make the whole looped tether proposition unfeasible, but then again I know that it's something that has had to have been worked out for the current single tether plans, too.

Re:Space elevator power? (1)

SoupIsGoodFood_42 (521389) | more than 5 years ago | (#26944269)

Wouldn't it just make more sense to have solar panels in orbit and transmit the power along the space elevator?

I imagine it might add too much weight or complexity. Even just running two strips of conductive tether separated by an insulator may be too much considering how feasible the tether is to begin with. Then there are things such as resistance to consider. Might simply be easier to beam it seperatly rather than add another layer of complexity to something that is already pushing the limits.

Re:Space elevator power? (1)

Patch86 (1465427) | more than 5 years ago | (#26944683)

While maybe yes (and maybe no), you're getting ahead of yourself.

All you need for the "space elevator" to work is a massive cable with one end anchored to an orbital, the other on Earth. The idea of it is to use an elevator to move materials from the surface into space.

To build a really decent power station in space, you're going to need to move a lot of materials from the surface up into orbit. Presumably the cheapest way to do this is to use your newly built space elevator- but you're going to need to power it.

So to build a nice orbital power station, we're going to want to find a way of powering the elevator from the surface first.

Maybe.

IANAS (I am not a scientist).

Re:Space elevator power? (1)

AmigaMMC (1103025) | more than 5 years ago | (#26945287)

Except that recently the space elevator was deemed "impossible" because even with nanotubes of carbon molecules there would be too much constant structural damage. Hey, I was bummed out too. Sorry, don't have the link handy. It had to do with japanese researchers.

Re:Space elevator power? (0)

Anonymous Coward | more than 5 years ago | (#26946037)

What a bunch of baloney, space elevator... The easiest way to space is by electromagnetic launch from a high altitude balloon. Building an appendage to the planet is very looney at best.

Re:Space elevator power? (1)

Archimboldo (847057) | more than 5 years ago | (#26951035)

Wouldn't it just make more sense to have solar panels in orbit and transmit the power along the space elevator?

Solar panels are great for powering electronics, which only need to move electrons, and small servos, which don't use much power. To lift payloads, I'm afraid sunlight is just too diffuse to do the job.

Re:Space elevator power? (2, Insightful)

robthebloke (1308483) | more than 4 years ago | (#26956683)

A large metal wire cutting through the earths magnetic field is all you need to generate electricity (ask anyone who plays the electric guitar). All you need to do is find a way to harness the current that would be generated in the space elevator cable.

If you attempted to stick a current through the elevator cable, my primitive understanding of physics says, oscillations will start to occur in the cable due to the way magnetism and electricity are related?

A what? (2, Funny)

Anonymous Coward | more than 5 years ago | (#26941301)

CECE is a new deep throttling engine

Took me a second look to realize that I'd read it wrong the first time...

Re:A what? (1)

wengkius (915283) | more than 5 years ago | (#26941571)

I'd mod this up if I had points left. Same thing happened to me.

Re:A what? (1)

onemorechip (816444) | more than 5 years ago | (#26942385)

It's a step toward the soixante-neuf drive used by the ship Hwang Ho in Philip Jose Farmer's (under the peudonym of Kilgore Trout) "Venus on the Half Shell". So named because it could achieve 69000 times the speed of light, obviously.

a new moon engine? (-1, Troll)

Anonymous Coward | more than 5 years ago | (#26941349)

Is that when the head of NASA (our esteemed vice president of these United States) bends over, drops his pants and lets one loose?

In other news. . . (0, Troll)

jlb0057 (1143241) | more than 5 years ago | (#26941403)

the DoD is offering a $2 trillion dollar prize to anyone who develops precision orbital bombardment of select areas in Afghanistan and Pakistan.

Re:In other news. . . (1)

William Robinson (875390) | more than 5 years ago | (#26941717)

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?

Re:In other news. . . (1)

smidget2k4 (847334) | more than 5 years ago | (#26942453)

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.

Re:In other news. . . (1)

jamstar7 (694492) | more than 5 years ago | (#26943501)

Interesting idea.

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?

Re:In other news. . . (1)

bcmm (768152) | more than 5 years ago | (#26945231)

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.

cool (0)

Anonymous Coward | more than 5 years ago | (#26941431)

In fact, very cool.

Of course they are testing. (1)

rokj (933990) | more than 5 years ago | (#26941793)

I wonder how much testing they did for Apollo mission.

Obligatory... (0)

Anonymous Coward | more than 5 years ago | (#26941975)

"... thats no moon!!"

Land almost anywhere (0)

Anonymous Coward | more than 5 years ago | (#26942191)

> "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."

But engeineers simply can't make it land anywhere on earth.

Re:Land almost anywhere (1)

khallow (566160) | more than 5 years ago | (#26942411)

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 [blogspot.com] to maintain nozzle efficiency (and ISP) in atmosphere. 3) There are other means of landing on Earth (eg, parachutes).

New? They had these in 1936! (2, Informative)

Richard Kirk (535523) | more than 5 years ago | (#26942755)

See... http://www.luft46.com/misc/sanger.html [luft46.com] 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.

Re:New? They had these in 1936! (1)

DerekLyons (302214) | more than 5 years ago | (#26947291)

Actually, if you read the page - you'll note that rocket engines are specified, not jet engines.

Humm along... (1)

zenspeaks (1337157) | more than 5 years ago | (#26943643)

If you were Australian, they'd take you to the moon and back for just being their baby.

Orbital Carbon Observatory Isn't (1, Troll)

thethibs (882667) | more than 5 years ago | (#26945791)

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.

Re:Orbital Carbon Observatory Isn't (1)

ibsteve2u (1184603) | more than 5 years ago | (#26946539)

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 see what you mean. Already I am having to factor in the assumption that your analysis is correct.

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