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#1 2004-11-17 12:18:52

Palomar
Member
From: USA
Registered: 2002-05-30
Posts: 9,734

Re: Space Elevator @ MIT

*Where the heck did the space elevator thread in this folder go??  Maybe "Search" is going bonkers (I also searched with "LiftPort").  I don't see that this has been posted previously.

Anyway -- hot off space.com's "Astronotes" press:

November 17

Space Elevator Climbs at MIT

It was one small climb for the space elevator last week at the Massachusetts Institute of Technology (MIT) in Cambridge.

From high atop the roof of MIT’s Cecil and Ida Green Building, a tether was lowered to the ground as curious onlookers watched the display in suspended belief under snowy conditions.

A scale model of a robot lifter successfully made its way up the lengthy ribbon, under the watchful eye of Michael Laine, president and founder of LiftPort Incorporated. Based in Bremerton, Washington, LiftPort is a for-profit company devoted to the commercial development of an elevator to space. The lifter was designed by LiftPort's David Shoemaker.

A lifter is a robotic cargo and construction car, a key element of the space elevator mass transportation system that would stretch from an ocean platform up, up and way beyond geosynchronous orbit.

The event was part of SpaceVision 2004, hosted November 11-14 by the Students for the Exploration and Development of Space (SEDS) and the MIT Mars Society.

Heres]http://www.space.com/php/multimedia/imagedisplay/img_display.php?pic=h_mit_elevator-test_02.jpg]Here's the pic (too large to include under Image; caption below:)

LiftPort's scale model of a robot lifter successfully made its way up a tether at MIT's Cecil and Ida Green Building. Credit: Tom Nugent/LiftPort
(Click to Enlarge)

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#2 2004-11-17 12:24:46

BWhite
Member
From: Chicago, Illinois
Registered: 2004-06-16
Posts: 2,635

Re: Space Elevator @ MIT

I was there. Saw it. We still need those carbon nano-tubes.

Space elevators are a long ways off and I remain unconvinced we can have sufficient through-put to justify the capital investment without a program of permanent settlement to create very substantial and sustainable demand.

The base of that thing will need to run like O'Hare Airport to have any hope of making money.


Give someone a sufficient [b][i]why[/i][/b] and they can endure just about any [b][i]how[/i][/b]

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#3 2004-11-17 15:26:05

Martian Republic
Member
From: Haltom City- Dallas/Fort Worth
Registered: 2004-06-13
Posts: 855

Re: Space Elevator @ MIT

I was there. Saw it. We still need those carbon nano-tubes.

Space elevators are a long ways off and I remain unconvinced we can have sufficient through-put to justify the capital investment without a program of permanent settlement to create very substantial and sustainable demand.

The base of that thing will need to run like O'Hare Airport to have any hope of making money.

I agree with you Bill.

So let build a city on the Moon of say ten thousand people. That should be enough for a start.

Larry,

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#4 2004-11-18 10:00:38

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 29,433

Re: Space Elevator @ MIT

I would have enjoyed see that but alas I do not have that ability to do so.
Question, how much weight was the proto type and what was the amount of payload it simulated to move up the ribbon.

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#5 2004-11-18 13:11:15

Palomar
Member
From: USA
Registered: 2002-05-30
Posts: 9,734

Re: Space Elevator @ MIT

http://www.universetoday.com/am/publish … 2004]Build SE on the MOON first? 

*Hmmmm.  Comments/questions later (super busy right now).

With this recent related thread, didn't want to create a new one.

--Cindy

::edit:: 

There are, however, five places in the Earth-Moon system where you could put an object of low mass - like a satellite... or a space elevator counterweight - and have them remain stable with very little energy: the Earth-Moon Lagrange points. The L1 point, a spot approximately 58,000 km above the surface of the Moon, will work perfectly.

*Is a rather lengthy article and my brain's just not up to visualizing the descriptive right now.  :-\  More later...

::edit 2::

The mission could even include a small solar powered climber which could climb up from the lunar surface to the top of the cable, and deliver samples of moon rocks into a high Earth orbit. Further missions could deliver whole teams of climbers, and turn the concept into a mass production operation.

The advantage of connecting an elevator to the Moon instead of the Earth is the simple fact that the forces involved are much smaller - the Moon's gravity is 1/6th that of Earth's. Instead of exotic nanotubes with extreme tensile strengths, the cable could be built using high-strength commercially available materials, like Kevlar or Spectra. In fact, Pearson has zeroed in on a commercial fibre called M5, which he calculates would only weigh 6,800 kg for a full cable that would support a lifting capacity of 200 kg at the base. This is well within the capabilities of the most powerful rockets supplied by Boeing, Lockheed Martin and Arianespace. One launch is it takes to put an elevator on the Moon.

*Cool!  smile  Really like the solar-powered climber concept too.


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#6 2004-11-18 18:48:12

Shaun Barrett
Member
From: Cairns, Queensland, Australia
Registered: 2001-12-28
Posts: 2,843

Re: Space Elevator @ MIT

Brilliant, Cindy!
    Many thanks for bringing this to our attention, or at least to my attention(! ). Others here may have been familiar with this idea for years but, to me, it's news. I can't believe Jerome Pearson's work on lunar SEs has been out there since 1979 and I've managed to miss it!  yikes

    I've always tended to dismiss a lunar space elevator because of the Moon's slow rotation rate. And, although I've known about the Earth-Moon Lagrange points for ages too, it never occurred to me to put the two concepts together! (Slaps forehead in frustration at own stupidity! )
    Through my retrospectoscope, the idea is now so very obvious.   roll

    Even just reading through the article, and noticing the reference to possible water ice resources at the lunar poles, I was mentally 'talking-down' Pearson's enthusiasm by imagining the transport problems involved in dragging tons of ice (if it's obtainable) to the elevator base at the equator. But no, once again Pearson's genius and imagination left me far behind him; he simply connects another cable from the pole to the counterweight .. wonderful!
    There are just a couple of problems I have with the polar cable, though. Firstly, no one is really very confident the much-vaunted lunar ice will be in  user-friendly 'large-frozen-lake' form, and thus practical to mine. And, secondly, dropping a cable down to the lunar equator from the counterweight seems straightforward enough, because it's just a gravitational balancing act on a line between the Moon's and Earth's centres of mass, but how do you connect up the counterweight and the pole? Knowing this guy Pearson a little better now, though, I'm sure he's thought of that already and has a neat technique all worked out!   :;):

    I'm looking forward to hearing more about all this. Excellent stuff!   :up:   smile


The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down.   - Rita Rudner

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