Space Elevators Michael Howard 10 31 12 Pros

Space Elevators Michael Howard 10 -31 -12

Pros and Cons § Benefits § Cheaper space travel § Allows for many more trips into space § Problems § Requires a very strong and light material § Will be costly to build

What is a Space Elevator? § Rope attached to the Earth near the equator which extends directly into space and is attached to a small counterweight in geostationary orbit § Will be able to transfer materials and eventually humans into space for much cheaper than it costs now

Why Does the Tether Stay Up? § Because the force of gravity at the bottom and the upward/outward centrifugal force at the top compete keeping the rope taut

The Platform § Will be placed along the equator so it will be located in the same place in the sky for ground observers § Built on a ship so it can be moved

The Tether § Will be made of 22, 000 mile long carbon nanotube strands because it is currently the only option which has the proper strength and is light enough § Will need to be wider at geosynchronous altitude where it will experience the most stress and taper down as it approaches earth

The Climber § It will be powered by lasers and solar power § It is estimated that the climb will take about 5 days

Climber

Counterweight § Captured asteroid § Space station above geostationary orbit

Benefits § Currently, the cost to launch a shuttle is about $10, 000/lb § Mechanical lifters attached to cable could carry cargo up to space for about $100 to $400 per pound

Elevator vs. Rocket § While rockets will undoubtedly improve greatly in efficiency there is a limit to how efficient they can become § The elevator will be the next step

Space tourism § A space elevator could help many people realize their dream of traveling into space

Problems with the elevator § Will require a strong material such as carbon nanotubes which we don’t currently possess the ability to form into a long enough tether § Will the public be convinced it is a good idea

Cost to build it § The space elevator will be the longest structure ever built but it will be simple § Estimated cost to build the space elevator is about $10 billion § Approximate cost of building a space shuttle is about 1. 7 billion and it costs about $450 million per mission § Endeavor completed 25 missions before being retired

Would it be Safe? § Space debris § Cable snaps § Storms § Terrorism

Conclusion § The future of space travel § Would set us on the path towards expanding our space exploration to places might never reach relying solely on rockets § Philip Ragan, co-author of the book "Leaving the Planet by Space Elevator", states that "The first country to deploy a space elevator will have a 95 percent cost advantage and could potentially control all space activities. "

References § http: //www. pbs. org/wgbh/nova/space/spac e-elevator. html § http: //www. howstuffworks. com/spaceelevator. htm § http: //www. spaceward. org/elevator § http: //phys. org/news 151938445. html § http: //nextbigfuture. com/2009/01/cambridg e-making-carbon-nanotubes. html