SPACE ELEVATOR
SPACE ELEVATOR: A NEW WAY TO REACH THE STARS
The Space Elevatoris a cable-like tool which could connect the Earth with a fixed structure in outer space.
It would provide a permanent link between Earth and outer space.
The Space Elevator in Science Fiction
Properties Of Carbon NanotubesStrong– 200 times stronger than steel.
– the first synthetic material to have greater strength than spider silk.
Light
– 1 square kilometre = 30kg
Flexible
– Compared to most materials.
Heat resistant– resists burning like a metal.
Ribbon Design The final ribbon is one-
meter wide and composed of parallel high-strength fibers
Interconnects maintain structure and allow the ribbon to survive small impacts
Initial, low-strength ribbon segments have been built and tested
Climbers Climbers built with
current satellite technology
Drive system built with DC electric motors
Photovoltaic array (GaAs or Si) receives power from Earth
7-ton climbers carry 13-ton payloads
Climbers ascend at 200 km/hr
8 day trip from Earth to geosynchronous altitude
Power BeamingPower is sent to deployment spacecraft and climbers by
laserSolid-state disk laser produces kWs of power and being
developed for MWatts Mirror is the same design as conventional astronomical
telescopes (Hobby-Eberly, Keck)
Anchor
Anchor station is a mobile, ocean-going platform identical to ones used in oil drilling
Anchor is located in eastern equatorial pacific, weather and mobility are primary factors
Challenges Induced Currents: milliwatts and not a problem Induced oscillations: 7 hour natural frequency couples poorly
with moon and sun, active damping with anchor Radiation: carbon fiber composites good for 1000 years in
Earth orbit (LDEF) Atomic oxygen: <25 micron Nickel coating between 60 and 800
km (LDEF) Environmental Impact: Ionosphere discharging not an issue Malfunctioning climbers: up to 3000 km reel in the cable,
above 2600 km send up an empty climber to retrieve the first Lightning, wind, clouds: avoid through proper anchor location
selection Meteors: ribbon design allows for 200 year probability-based
life LEOs: active avoidance requires movement every 14 hours on
average to avoid debris down to 1 cm Health hazards: under investigation but initial tests indicate
minimal problem Damaged or severed ribbons: collatoral damage is minimal
due to mass and distribution
Advantages
Low operations costs - US$250/kg to LEO, GEO, Moon, Mars, Venus or the asteroid belts
No payload envelope restrictions No launch vibrationsSafe access to space - no explosive propellants or dangerous launch or re-entry
forcesEasily expandable to large systems or multiple systemsEasily implemented at many solar system locations
The space elevator is a revolutionary Earth-to-space transportation system that will enable space exploration
Design, deployment and operational scenarios for the first space elevator have been put together. Potential challenges have been laid out and solutions developed.
Development of the space elevator requires an investment in materials and engineering but is achievable in the near future with a reasonable investment and development plan.
Summary
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1082. 12p. • Pugno, N. M. (2006). On the strength of the carbon nanotube-based space elevator cable: from nanomechanics to
megamechanics. Journal of Physics: Condensed Matter, 18(33), S1971• Pugno, N.M.(2013). Towards the artsutanov’s dream of the space elevator. the ultimate design of a 35 GPa strong tether
thanks to graphene. Acta Astronautica. Feb2013, Vol. 82 Issue 2, p221-224.• Takeichi, N. (2012). Geostationary station keeping control of a space elevator during initial cable deployment. Acta
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