1. Space Elevators
Michael Howard

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

3. 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

5. 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

6. 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

7. 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

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

9. Climber

10. Counterweight Captured asteroid
Space station above geostationary orbit

11. 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

12. 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

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

14. 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

15. 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

16. Would it be Safe?
Space debris
Cable snaps
Storms
Terrorism

17. 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."

18. References http://www.pbs.org/wgbh/nova/space/space-elevator.html