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Rockets: So Old School? ("Space Elevator" coming?)
The Huffington Post ^ | November 8, 2012 | Seth Shostak, Senior Astronomer, SETI Institute

Posted on 08/04/2014 12:12:44 AM PDT by 2ndDivisionVet

Could rocket scientists be an endangered species?

You're probably betting "no," given the contemporary efforts to hurl hardware to the moon, to Mars, and to a passel of other unearthly locales. The rocket biz is busy, and it's diversifying. An enthusiastic troupe of private companies is also getting into the act, hoping to cash in by lifting off.

It seems that "rocket scientist" is a job category that's here for the long haul, like "mortician." But all this activity masks an important point: rockets are not a terribly efficient way to lift things into space. For every pound of payload, there are typically 25 pounds of rocket and fuel, and in some cases the vehicle is just thrown away after use. Rockets also suffer from a heavy foot on the accelerator, subjecting payloads and passengers to G-forces that warp faces into Botox ads. In addition, and despite nearly a hundred years of building these flame-belching devices, they're still vulnerable to colorful self-destruction. This is probably not a list of features you would accept in your next family car.

However, there's an intriguing alternative to traditional reaction technology that could beat rockets at their own game. It's called the space elevator.

What's a space elevator? Simply described, it's a thin ribbon, about 3 feet wide and 60 thousand miles long, stretching upwards from the surface of the Earth. The lower end is bolted to a heavy anchor (think of an oil drilling platform), and the top is capped with a counterweight. It's all arranged so that the center of mass falls at the geosynchronous orbital point, about 22,000 miles up. Like a rock on a string swung 'round your head, the ribbon is under tension, stays straight, and rotates with the Earth....

(Excerpt) Read more at huffingtonpost.com ...


TOPICS: Business/Economy; Government; Science; Travel
KEYWORDS: mars; rockets; space; spacetravel

1 posted on 08/04/2014 12:12:44 AM PDT by 2ndDivisionVet
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To: 2ndDivisionVet

I thought there were possibilities using lasers or microwave.


2 posted on 08/04/2014 12:36:18 AM PDT by Vendome (Don't take life so seriously-you won't live through it anyway-Enjoy Yourself ala Louis Prima)
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To: 2ndDivisionVet
According to space systems engineer Peter Swan, Director of the International Space Elevator Consortium, this device is about three to four decades away.

I think I first read about space elevators when I was a teen more than thirty years ago.

I don’t think they are any closer to reality now.

Anybody remember the space tether experiment failure of STS-75.

A space elevator would generate a considerable amount of current traveling down the shaft.

Space Tether Experiment

3 posted on 08/04/2014 12:53:07 AM PDT by Pontiac (The welfare state must fail because it is contrary to human nature and diminishes the human spirit.)
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To: 2ndDivisionVet
Although there are many technical problems with the "space elevator" (for example, atmospheric corrosion of carbon nanotube structures make the structure's long-term viability questionable), even if it is ever built, it cannot be used to transport people. It traverses the van Allen radiation belts too slowly, causing excessive radiation exposure to human passengers.

Great for cargo, but people will still need rockets to go to space, both to LEO and beyond GEO from the space elevator terminus.

4 posted on 08/04/2014 12:55:22 AM PDT by Cincinatus (Omnia relinquit servare Rempublicam)
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To: Vendome

HAH! I thought this was possible using a geosynchronous orbit. I had imagined it would need to be much bigger and sturdier. But would the atmosphere of the Earth somehow disrupt the orbit? I am thinking that the ribbon would have to be slack....because if strong enough winds push it, it could slow down or speed up the anchor at the space end just enough that the orbit could deteriorate.


5 posted on 08/04/2014 12:58:19 AM PDT by FreedomStar3028 (Evil must be punished.)
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To: 2ndDivisionVet

It will take a super-material to support the weight.


6 posted on 08/04/2014 1:05:30 AM PDT by Lurkina.n.Learnin (It's a shame nobama truly doesn't care about any of this. Our country, our future, he doesn't care)
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To: 2ndDivisionVet

Supposedly the economics of Spacex’s fully reusable launch vehicles are better than a space tether. I doubt this will be used, as a catastrophic accident would cause 10,000 miles or so of cable to come down anywhere around the equator, and there are populated areas on the equator.


7 posted on 08/04/2014 1:12:40 AM PDT by Vince Ferrer
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To: Vince Ferrer

I don’t think we will see a space elevator any time soon


8 posted on 08/04/2014 1:15:28 AM PDT by GeronL (Vote for Conservatives not for Republicans)
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To: Pontiac

A space elevator would generate a considerable amount of current traveling down the shaft.

Maybe that’s the answer to our energy problems.


9 posted on 08/04/2014 1:18:27 AM PDT by tet68 ( " We would not die in that man's company, that fears his fellowship to die with us...." Henry V.)
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To: tet68
Well if you read the article that I linked to you will see that the space tether failed because the current and voltage traveling on the tether cause heating in the tether causing it to fail.

A space elevator would be exposed to all kinds of weather extremes including space weather.

Even minor solar mass ejections can produce high currents in surface electric transmission lines. Consider the potential currents that a space elevator mighty be subjected to.

I think that there may be all kinds of engineering hurdles yet to be thought of for a space elevator.

10 posted on 08/04/2014 1:37:05 AM PDT by Pontiac (The welfare state must fail because it is contrary to human nature and diminishes the human spirit.)
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To: 2ndDivisionVet
The problems are not trivial. The article proposes a 60,000 mile "ribbon". That's a fair amount of slack, considering the geo-synchronous orbit altitude is 22,500 miles. Nevertheless, a 60,000 mile long cable has to be at least able to support it's own weight.

I recall in the 70's, visiting a oil rig support supplier. They had sensors to drop into oil wells to determine the exact position of the well point. The sensors could be dropped as much as one mile. The sensor weighed 1-2 pounds. The electrical cable to connect it weighed hundreds of pounds, and could only support its own weight plus the sensor for several hundred feet. Steel cable was used to support it beyond this.

But, of course, the steel cable must also support its own weight. There were huge (8 foot diameter)coils of high strength one inch diameter steel cables to simply drop this little sensor into an oil well. All this was for a ONE MILE elevator, to drop a 2 pound sensor into an oil well.

A 60,000 mile elevator is much much more complicated than just 60,000 times worse.

11 posted on 08/04/2014 3:38:01 AM PDT by norwaypinesavage (The Stone Age didn’t end because we ran out of stones)
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To: 2ndDivisionVet

Even if we had the material technology to build such a ribbon, how would we deploy it? A spool big enough to hold 60,000 miles of ribbon would be pretty big!


12 posted on 08/04/2014 3:46:35 AM PDT by Flick Lives ("I can't believe it's not Fascism!")
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To: Pontiac

Arthur C Clarke came up with the idea.


13 posted on 08/04/2014 3:51:59 AM PDT by wiggen (The teacher card. When the racism card just won't work.)
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To: 2ndDivisionVet

This is a really dumb idea.


14 posted on 08/04/2014 4:23:20 AM PDT by I want the USA back (Media: completely irresponsible. Complicit in the destruction of this country.)
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To: 2ndDivisionVet; wiggen
This is a prime candidate for NIMBY (Not In My Back Yard) action. The legal filings would probably equal the height of the 'space elevator' and end it before it gets started.

Arthur C Clarke came up with the idea.
While Mr Clarke is given the major credit for popularization of the concept and value of geosynchronous / geostationary satellites he is much less so for the idea of the "space elevator" although his novel on it, "Fountains of Paradise" (1979) was quite enjoyable and informative. However, the concept of space elevators date back to a thought experiment by the great Russian space theorist, Konstantin Tsiolkovsky, in 1895. Since then there have been multiple iterations, studies and story lines about it. Funny enough, almost simultaneous with Clarke's novel came fellow Brit-born author, Charles Sheffield's "Web Between Worlds" which I think did a better stab at the required engineering, but that is my opinion!

15 posted on 08/04/2014 4:52:48 AM PDT by SES1066 (Quality, Speed or Economical - Any 2 of 3 except in government - 1 at best but never #3!)
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To: Cincinatus

“It traverses the van Allen radiation belts too slowly, causing excessive radiation exposure to human passengers.”

That depends on the allowable size and weight of the compartment. A larger elevator could have shielding.

The bigger problem with the concept is what happens when a meteor, space junk or human action severs it...


16 posted on 08/04/2014 5:43:01 AM PDT by PreciousLiberty
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To: 2ndDivisionVet

Why build a space elevator when I’ve got some magic beans I’m willing to sell and they will do the exact same thing at half the price.


17 posted on 08/04/2014 5:53:29 AM PDT by IMR 4350
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To: 2ndDivisionVet
this is an example of folks starting on a project without even a basic understanding of fundamental principles.

The electrical potential (Voltage) between the ground and the atmosphere above: "...ground‐level electric fields ranged from 3.2 to 7.6 kV per meter."

For all the gory details go here:>>

http://onlinelibrary.wiley.com/doi/10.1029/2011JD015710/pdf

For the uninformed that amounts to 7,600,000 Volts per kilometer of elevator height.

I love it when liberals become "scientists" 'cause they believe in magical thinking - whatever hair-brained scheme they can think up, can happen just because they thought of it.

Lurking'

18 posted on 08/04/2014 5:59:54 AM PDT by LurkingSince'98 (Ad Majoram Dei Gloriam = FOR THE GREATER GLORY OF GOD)
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To: 2ndDivisionVet

How long would it take an elevator to go 60,000 miles.

And the thing would be a terrorist magnet.


19 posted on 08/04/2014 6:04:54 AM PDT by aomagrat (Gun owners who vote for democrats are too stupid to own guns.)
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To: 2ndDivisionVet

Is it like the Maxwell House Elevator? Good to the last drop.


20 posted on 08/04/2014 6:33:40 AM PDT by mfish13 (Elections have Consequences.)
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To: 2ndDivisionVet
So how are the Palis going to harass Israel with a frickin' space elevator? Clearly a racist idea.
21 posted on 08/04/2014 7:10:30 AM PDT by Moltke (Sapere aude!)
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To: 2ndDivisionVet

The technical problems of a “Space Elevator” are VERY DAUNTING. I believe that anyone that waves their hand and says, “We are only 30 or so years from seeing Space Elevators” does not really have a grasp on the MAGNITUDE of the issues facing such a structure.

Now, that being said, such things get done in a “divide and conquer” kind of way.

Material researchers that have no interest in “Space Elevators” will probably end up creating some carbon construct suitable for use as the “ribbon”.

Electrical Engineers looking at other problems might inadvertently find solutions to the power dissipation issue.

Breakthroughs in conventional rocket launching might make putting materials in orbit to build an elevator more practical.

I would never say “never”, but I am firmly in the “Not in 30 Years” camp.


22 posted on 08/04/2014 7:20:21 AM PDT by Rebel_Ace (Tags?!? Tags?!? We don' neeeed no stinkin' Tags!)
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To: I want the USA back
This is a really dumb idea.

Beam me up, Scotty. There's no intelligent life down here.

23 posted on 08/04/2014 7:31:50 AM PDT by JimRed (Excise the cancer before it kills us; feed & water the Tree of Liberty! TERM LIMITS NOW & FOREVER!)
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To: LurkingSince'98
For the uninformed that amounts to 7,600,000 Volts per kilometer of elevator height.

Can we harvest all those volts to fuel our Volts?

24 posted on 08/04/2014 7:33:15 AM PDT by JimRed (Excise the cancer before it kills us; feed & water the Tree of Liberty! TERM LIMITS NOW & FOREVER!)
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