A Space Elevator We Could Build Now

The idea of a space elevator that could carry payloads into orbit without a rocket has been around for quite a while. But the materials strong and light enough to make it practical don't exist yet.

However, there's now a design for a space elevator that uses materials that exist now and could be built with current technology. What makes it possible is that it would be anchored on the moon and go to geosynchronous orbit.

The researchers’ main result is to show that today’s strongest materials—carbon polymers like Zylon—could comfortably support a cable stretching from the moon to geosynchronous orbit. They go on to suggest that a proof-of-principle device made from a cable about the thickness of a pencil lead could be dangled from the moon at a cost measured in billions of dollars.

That’s clearly ambitious but by no means excessive for modern space missions. “By extending a line, anchored on the moon, to deep within Earth’s gravity well, we can construct a stable, traversable cable allowing free movement from the vicinity of Earth to the Moon’s surface,” say Penoyre and Sandford.

The savings would be huge. “It would reduce the fuel needed to reach the surface of the moon to a third of the current value,” they say.

While this is technically feasible, I question whether it makes economic sense. But it would be a heck of a trip, if a long one (at 1,600 km./hr. it would take almost 10 days).