When proponents of carbon nanotubes (CNTs) first introduced them to the public, claiming them to be one of the strongest materials by weight in the world, one of the beneficiary applications they trotted was the space elevator.
The notion of a space elevator had been around for some time before CNTs came along to reinvigorate it. But with the introduction of carbon-nanotube composites in around 2000, the idea started to gain more widespread acceptance. And it’s never really lost traction, with blogs sprouting up and conferences being held.
Although it dates back a few years now, IEEE Spectrum did a pretty thorough run down on the potential of actually building a space elevator.
It all seemed a bit far-fetched but there were respected scientists who believed it was possible. Nonetheless it didn’t seem as though anyone, or, better put, any company, was willing to take the bold step of setting out to build one.
That is, until now. Obayashi Corp., headquartered in Tokyo, Japan, has announced that it intends to build a space elevator by the year 2050.
With a project deadline 38 years hence, the company has certainly given itself plenty of wiggle room. But you have to wonder why would a company that is described as a major construction company make any plans of the sort?
Whatever the reason, they have made the announcement and naturally, they have turned to carbon nanotubes. While CNTs have long been heralded as the only material that could be light and strong enough to carry out the job, there have been some doubts as to whether material could actually do it.
One commenter to theIEEE Spectrum piece noted as recently as 2009: “The current limited understanding of the CNT growth process and the inter-fiber forces in a spun yarn does not allow us to build a sufficiently strong wire for the space elevator from CNTs.” Strength is not the only problem apparently. It seems they can’t grow a wire from CNT that is long enough.
Without a material as yet up to the job it raises the question again: Why make this announcement?
We do get a hint as to why in the press release as an Obayashi official says, “We'll try to make steady progress so that it won't end just up as simply a dream."
Sometimes I guess you just have to dream big.
Dexter Johnson is a contributing editor at IEEE Spectrum, with a focus on nanotechnology.