After being first envisioned by Konstantin Tsiolkovsky, then perfected by Yuri Artsutanov, Jerome Pearson and Brad Edwards, the space elevator has captured the imaginations of thousands of individuals who believe it’s humanities best hope for colonizing the solar system en masse.
This radical space concept led to the creation of two startups (LiftPort and Blackline Ascension), as well as support from NASA who (despite their skepticism) is offering $4 million in prize money towards successful teams/companies (thanks in part to their Centennial Challenge).
Despite the momentum that the space elevator community has built up over the years, their dreams of a 100,000 km “beanstalk” stretching into the heavens may not come to pass as the earliest plans for a structure coming into being hover around 2030.
Rather than spend decades perfecting carbon nanotubes and power climbers (key ingredients if a traditional space elevator is to become a reality), it may be better to focus on Skyhooks (aka orbital space elevators) instead.
While a traditional space elevator would require a massive counterweight at the end (i.e. an asteroid or a large space station), a Skyhook would only need a light counterweight at the top of the structure, which might be feasible with today’s technology (not to mention this economy as well).
A Skyhook would also be much shorter than their traditional brethren, spanning a length of no more than 4,000 km compared to 100,000 km for a traditional space elevator. Even if a Skyhook’s cable had to be fashioned from carbon nanotubes (which may not be needed as Kevlar and/or Spectra might be sufficient), it would be much easier to fashion due to its shorter length.
Last but not least, Skyhooks would probably not need to beam power to their transport climbers from below, a feat that may be extremely difficult for traditional space elevators (especially 100,000 km away!). Instead, climbers transporting cargo on a Skyhook could be powered by miniature nuclear reactors or via solar power from the rays of the sun.
Although Skyhook’s have a significant advantage over their earth bound friends, their Achilles heal lies in the fact one would need to construct a rocket/jet hybrid capable of “breathing air” when flying through our atmosphere, and later on switching to rocket engines when they reach the edge of space.
While space elevator enthusiasts may still opt to construct their terrestrial beanstalk in an attempt to link heaven and earth, it may be wiser to focus their efforts on Skyhooks instead–especially now that companies like Lockheed Martin may seriously pursue building a Skyhook which in the end could help open the final frontier to the masses.