Space elevators
Another Important Idea That Everyone Should Know About :-)
Capture a small asteroid. Stick it into geosynchronous orbit above a reasonably stable part of the Equator. Attach it to the ground with a big cable. It will need to be a very strong cable to support its own weight (to reach geosynchronous orbit, it would have to be nearly 36,000 km long), so you'd better make it out of carbon nanotubes. Run a railway line up the side. Ta-da! You've just reduced the cost of reaching geosynchronous orbit by a factor of more than 100.
What you have just built is called a Space Elevator.
This idea isn't actually as daft as I've just made it sound, and some very bright people (including NASA) are working on building one. In fact, if you want to go to Mars, it would probably be cheaper to build a space elevator first. These guys reckon they can do it by 2031. There's lots more information in the Wikipedia article linked; I'd also recommend Arthur C. Clarke's excellent novel The Fountains of Paradise, which is half about the construction of a space elevator and half about his beloved Sri Lanka.
Capture a small asteroid. Stick it into geosynchronous orbit above a reasonably stable part of the Equator. Attach it to the ground with a big cable. It will need to be a very strong cable to support its own weight (to reach geosynchronous orbit, it would have to be nearly 36,000 km long), so you'd better make it out of carbon nanotubes. Run a railway line up the side. Ta-da! You've just reduced the cost of reaching geosynchronous orbit by a factor of more than 100.
What you have just built is called a Space Elevator.
This idea isn't actually as daft as I've just made it sound, and some very bright people (including NASA) are working on building one. In fact, if you want to go to Mars, it would probably be cheaper to build a space elevator first. These guys reckon they can do it by 2031. There's lots more information in the Wikipedia article linked; I'd also recommend Arthur C. Clarke's excellent novel The Fountains of Paradise, which is half about the construction of a space elevator and half about his beloved Sri Lanka.