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re-entry or impact the surface. A mechanism to immediately sever the cable below the station would prevent reentry of the station and result in its continuation in a high and slightly modified orbit. Simulations have shown that as the descending portion of the space elevator "wraps around" Earth, the stress on the remaining length of cable increases, resulting in its upper sections breaking off and being flung away. The details of how these pieces break and the trajectories they take are highly sensitive to initial conditions.
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71:). Unless these fast-moving projectiles can be stopped safely, they will break yet other fibers, initiating a failure cascade capable of severing the cable. The challenge of preventing fiber breakage from initiating a catastrophic failure cascade seems to be unaddressed in the current literature on terrestrial space elevators. Problems of this sort would be easier to solve in lower-tension applications (e.g., lunar elevators). This problem has been described by physicist
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26:. A space elevator would present a navigational hazard, both to aircraft and spacecraft. Aircraft could be dealt with by means of simple air-traffic control restrictions. Impacts by space objects such as meteoroids, satellites and micrometeorites pose a more difficult problem for construction and operation of a space elevator.
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of 1,000 gigapascals (150,000,000 psi), its strain will be 0.05 and its stored elastic energy will be 1/2 × 0.05 × 50 GPa = 1.25×10 joules per cubic meter. Breaking a fiber will result in a pair of de-tensioning waves moving apart at the speed of sound in the fiber, with the fiber segments
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For stability, it is not enough that other fibers be able to take over the load of a failed strand — the system must also survive the immediate, dynamical effects of fiber failure, which generates projectiles aimed at the cable itself. For example, if the cable has a working stress of 50
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If the break occurred at the counterweight side of the elevator, the lower portion, now including the "central station" of the elevator, would begin to fall down and would continue down to reentry if no part of the cable below failed as well. Depending on the size, it would either burn up on
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If the break occurred at higher altitude, up to about 25,000 kilometres (16,000 mi), the lower portion of the elevator would descend to Earth and drape itself along the equator east of the anchor point, while the now unbalanced upper portion would rise to a higher orbit.
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Furthermore, the effectiveness of the magnetosphere to deflect radiation emanating from the sun decreases dramatically after rising several earth radii above the surface. This ionising radiation may cause damage to materials within both the tether and climbers.
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If the elevator is cut at its anchor point on Earth's surface, the outward force exerted by the counterweight would cause the entire elevator to rise upward into a higher orbit, or escape Earth's gravity altogether.
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to any unshielded human or other living things. The inner belt would have to be crossed, where—behind a shield of three millimetres (0.12 in) of
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A.M. Jorgensena; S.E. Patamiab & B. Gassendc (February 2007). "Passive radiation shielding considerations for the proposed space elevator".
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must therefore be emptied of its charged particles. This has been proposed by the High
Voltage Orbiting Long Tether project.
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Corrosion is thought by some to be a risk to any thinly built tether (which most designs call for). In the upper atmosphere,
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There are risks associated with never-done-before technologies like the construction and operation of a
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449:(November 10–15, 1996). "High-Voltage Tethers For Enhanced Particle Scattering In Van Allen Belts".
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below the top of the elevator would eventually collide with the elevator cable.
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Other analyses show atomic oxygen to be a non-problem in practice.
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391:"Determination of the Radiation Dose of the Apollo 11 Mission"
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For a space elevator to be used by human passengers, the
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336:"Space elevators: "First floor, deadly radiation!""
451:APS Division of Plasma Physics Meeting Abstracts
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415:"ESA's Space Environment Information System"
582:Audacious & Outrageous: Space Elevators
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124:—the dose rate can reach 465 mSv/h.
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429:"The Van Allen Probes and Radiation Dose"
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47:gigapascals (7,300,000 psi) and a
541:"Animation of a Broken Space Elevator"
201: – Concepts for launch into space
195: – Proposed transportation system
87:steadily eats away at most materials.
513:Edwards, Bradley Carl (August 2005).
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321:"The Space Elevator: Phase II Study"
238:Clarke, Arthur C. (12 August 2003).
491:. Tethers Unlimited. Archived from
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573:Space elevator prize competitions
267:Space Tethers and Space Elevators
265:van Pelt, Michel (12 June 2009).
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445:Mirnov, Vladimir; Üçer, Defne;
377:10.1016/j.actaastro.2006.07.014
108:structure would lie inside the
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363:(3). Elsevier Ltd.: 189–209.
94:Radiation and Van Allen belts
577:The Space Elevator Reference
205:Space elevator construction
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684:Electromagnetic propulsion
334:Kelly Young (2006-11-13).
219:Space elevators in fiction
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459:American Physical Society
153:Cut up to about 25,000 km
144:Cut near the anchor point
709:Momentum exchange tether
539:Gassend, Blaise (2004).
515:"A Hoist to the Heavens"
210:Space elevator economics
133:Van Allen radiation belt
110:Van Allen radiation belt
100:Van Allen radiation belt
319:Edwards, Bradley Carl.
139:In the event of failure
838:Non-rocket spacelaunch
799:Konstantin Tsiolkovsky
199:Non-rocket spacelaunch
67:) round fired from an
848:Megascale engineering
299:European Space Agency
763:List of competitions
732:Lunar space elevator
595:at Wikimedia Commons
519:IEEE Spectrum Online
457:. College Park, MD:
292:"Corrosion in Space"
193:Lunar space elevator
467:1996APS..DPP..7E06M
369:2007AcAau..60..198J
162:Cut above 25,000 km
118:radiation poisoning
789:Bradley C. Edwards
569:2007-01-06 at the
477:. Abstract #7E.06.
185:Spaceflight portal
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591:Media related to
447:Danilov, Valentin
357:Acta Astronautica
276:978-0-387-76556-3
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544:. Retrieved
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843:Spaceflight
820:LaserMotive
727:Launch loop
659:In fiction
546:2007-01-14
499:2011-06-18
304:8 February
250:8 February
225:References
30:Satellites
649:Economics
475:205379064
122:aluminium
79:Corrosion
69:M16 rifle
863:Category
567:Archived
171:See also
36:perigees
742:Skyhook
463:Bibcode
365:Bibcode
61:caliber
777:People
654:Safety
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432:(PDF)
394:(PDF)
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471:OCLC
401:2022
306:2011
271:ISBN
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